Exercise programs for people with dementia

  • Conclusions changed
  • Review
  • Intervention

Authors


Abstract

Background

This is an update of our previous 2008 review. Several recent trials and systematic reviews of the impact of exercise on people with dementia are reporting promising findings. 

Objectives

Primary: Do exercise programs for older people with dementia improve cognition, activities of daily living (ADLs), challenging behaviour, depression, and mortality in older people with dementia?

Secondary: Do exercise programs for older people with dementia have an indirect impact on family caregivers’ burden, quality of life, and mortality?

Do exercise programs for older people with dementia reduce the use of healthcare services (e.g. visits to the emergency department) by participants and their family caregivers?

Search methods

We identified trials for inclusion in the review by searching ALOIS (www.medicine.ox.ac.uk/alois), the Cochrane Dementia and Cognitive Improvement Group’s Specialised Register, on 4 September 2011, and again on 13 August 2012. The search terms used were: 'physical activity' OR exercise OR cycling OR swim* OR gym* OR walk* OR danc* OR yoga OR ‘tai chi’.

Selection criteria

In this review, we included randomized controlled trials in which older people, diagnosed with dementia, were allocated either to exercise programs or to control groups (usual care or social contact/activities) with the aim of improving cognition, ADLs, behaviour, depression, and mortality. Secondary outcomes related to the family caregiver(s) and included caregiver burden, quality of life, mortality, and use of healthcare services.

Data collection and analysis

Independently, at least two authors assessed the retrieved articles for inclusion, assessed methodological quality, and extracted data. Data were analysed for summary effects using RevMan 5.1 software. We calculated mean differences or standardized mean difference (SMD) for continuous data, and synthesized data for each outcome using a fixed-effect model, unless there was substantial heterogeneity between studies, when we used a random-effects model. We planned to explore heterogeneity in relation to severity and type of dementia, and type, frequency, and duration of exercise program. We also evaluated adverse events.

Main results

Sixteen trials with 937 participants met the inclusion criteria. However, the required data from three trials and some of the data from a fourth trial were not published and not made available. The included trials were highly heterogeneous in terms of subtype and severity of participants' dementia, and type, duration and frequency of exercise. Only two trials included participants living at home. Our meta-analysis suggested that exercise programs might have a significant impact on improving cognitive functioning (eight trials, 329 participants; SMD 0.55, 95% confidence interval (CI) 0.02 to 1.09). However, there was substantial heterogeneity between trials (I2 value 80%), most of which we were unable to explain. We repeated the analysis omitting one trial, an outlier, that included only participants with moderate or severe dementia. This reduced the heterogeneity somewhat (I2 value 68%), and produced a result that was no longer significant (seven trials, 308 participants; SMD 0.31, 95% CI -0.11 to  0.74). We found a significant effect of exercise programs on the ability of people with dementia to perform ADLs (six studies, 289 participants; SMD 0.68, 95% CI 0.08 to 1.27). However, again we observed considerable unexplained statistical heterogeneity (I2 value 77%) in this meta-analysis. This means that there is a need for caution in interpreting these findings. In further analyses, we found that the burden experienced by informal caregivers providing care in the home may be reduced when they supervise the participation of the family member with dementia in an exercise program (one study, 40 participants; MD -15.30, 95% CI -24.73 to -5.87), but we found no significant effect of exercise on challenging behaviours (one study, 110 participants; MD -0.60, 95% CI -4.22 to 3.02), or depression (six studies, 341 participants; MD –0.14, 95% CI -0.36 to 0.07) . We could not examine the remaining outcomes, quality of life, mortality, and healthcare costs, as either the appropriate data were not reported, or we did not retrieve trials that examined these outcomes.

Authors' conclusions

There is promising evidence that exercise programs can have a significant impact in improving ability to perform ADLs and possibly in improving cognition in people with dementia, although some caution is advised in interpreting these findings. The programs revealed no significant effect on challenging behaviours or depression. There was little or no evidence regarding the remaining outcomes of interest.

Résumé scientifique

Les programmes d'exercice physique chez les patients atteints de démence

Contexte

Ceci est une mise à jour de notre précédente revue de 2008. Plusieurs essais récents et revues systématiques sur l'impact de l'exercice chez les personnes souffrant de démence rapportent des conclusions prometteuses.

Objectifs

Premièrement : Les programmes d'exercice physique peuvent-ils améliorer la fonction cognitive, les activités de la vie quotidienne (AVQ), le comportement turbulent, la dépression et la mortalité chez les personnes âgées atteintes de démence?

Deuxièmement : Les programmes d'exercice physique chez les personnes âgées souffrant de démence ont-ils un impact indirect relatif au fardeau de la famille et des proches aidants, à la qualité de vie et à la mortalité?

Les programmes d'activité physique chez les personnes âgées souffrant de démence réduisent-ils le recours aux services de santé (par exemple les visites aux urgences) par les participants et par les proches aidants?

Stratégie de recherche documentaire

Nous avons identifié des essais à inclure dans la revue en effectuant une recherche dans ALOIS (www.medicine.ox.ac.uk/alois), le registre spécialisé du groupe Cochrane sur la démence et les autres troubles cognitifs en date du 4 septembre 2011 et du 13 août 2012. Les termes de recherche utilisés étaient les suivants : « activités physiques » OU exercice OU vélo OU natation OU gymnastique OU marche OU danse OU yoga OU « tai chi ».

Critères de sélection

Dans cette revue, nous avons inclus des essais contrôlés randomisés dans lesquels les personnes âgées, présentant un diagnostic de démence, ont été assignées soit à des programmes d'exercices physiques, soit à des groupes témoins (soins habituels ou contact/activités sociales) dans le but d'améliorer la fonction cognitive, l’AVQ, le comportement, la dépression et la mortalité. Les critères de jugement secondaires liés au(x) proche(s) du soignant comprenaient le fardeau pour les soignants, la qualité de vie, la mortalité, et l'utilisation des services de santé.

Recueil et analyse des données

Au moins deux auteurs ont indépendamment évalué les articles trouvés pour l'inclusion, la qualité méthodologique et extrait les données. Les données des effets ont été analysées à l'aide du logiciel RevMan 5.1. Nous avons calculé la différence moyenne ou la différence moyenne standardisée (DMS) pour les données continues et synthétisé les données pour chaque critère de jugement en utilisant un modèle à effets fixes, sauf s' il y avait une hétérogénéité substantielle entre les études lorsque nous utilisions un modèle à effets aléatoires. Nous avions prévu d'étudier l'hétérogénéité en termes de gravité et du type de la démence et selon le type, la fréquence et la durée du programme d'exercices. Nous avons également évalué les effets indésirables.

Résultats principaux

Seize essais portant sur 937 participants remplissaient les critères d'inclusion. Cependant, les données requises issues de trois essais et certaines données issues d'un quatrième essai n'ont pas été publiées et n’étaient pas disponibles. Les essais inclus étaient très hétérogènes en termes de sous-type et de gravité de la démence des participants et selon le type, la durée et la fréquence de l'exercice. Seuls deux essais incluaient des participants vivant à domicile. Notre méta-analyse suggérait que les programmes d'exercices pourraient avoir un impact significatif sur l'amélioration du fonctionnement cognitif (huit essais, 329 participants; DMS de 0,55, intervalle de confiance (IC) à 95% de 0,02 à 1,09). Cependant, il y avait une hétérogénéité substantielle entre les essais (I 2 =80%), que nous ne sommes généralement pas parvenus à expliquer. Nous avons répété l'analyse excluant un essai qui incluait uniquement des participants atteints de démence modérée ou sévère. Cela a légèrement réduit l'hétérogénéité (I 2 =68%), et a produit un résultat qui n'était plus significatif (sept essais, 308 participants; DMS de 0,31, IC à 95% -0,11 à 0,74. Nous avons trouvé un effet significatif des programmes d'exercice physique sur la capacité des personnes souffrant de démence à réaliser les AVQ (six études, 289 participants; DMS de 0,68, IC à 95% de 0,08 à 1,27). Cependant et de nouveau dans cette méta-analyse, nous avons observé une importante hétérogénéité statistique inexpliquée (I 2=77%). Ces résultats doivent donc être interprétés avec précaution. Dans d'autres analyses, nous avons trouvé que le fardeau ressenti par les aidants naturels fournissant des soins à domicile pourrait être réduit lorsqu' ils supervisent la participation d’un proche ou d’un membre de la famille souffrant de démence dans un programme d'exercices (une étude, 40 participants; DM -15,30, IC à 95% -24,73 à -5,87), mais nous n'avons trouvé aucun effet significatif de l'exercice sur les comportements difficiles (une étude, 110 participants; DM -0,60, IC à 95% -4,22 à 3,02), ou sur la dépression (six études, 341 participants; DM -0.14, IC à 95% -0,36 à 0,07). Nous n'avons pas pu examiner les autres critères de résultat, la qualité de vie, la mortalité et les coûts de santé, soit du fait que les données n’étaient pas rapportées, soit du fait que nous n'avons pas extrait d’essais ayant examiné ces critères de jugement.

Conclusions des auteurs

Des preuves prometteuses indiquent que les programmes d'exercices peuvent avoir un impact significatif dans l'amélioration de la capacité à effectuer les AVQ et éventuellement dans l’amélioration de la fonction cognitive chez les personnes souffrant de démence, bien que ces résultats doivent être interprétés avec prudence. Les programmes n’ont révélé aucun effet significatif sur les comportements difficiles ou sur la dépression. Il n'y avait que peu ou pas de preuves concernant les autres critères de jugement d'intérêt.

Plain language summary

Exercise programs for people with dementia

Background

In future, as the population ages, the number of people in our communities suffering with dementia will rise dramatically. This will not only affect the quality of life of people with dementia but also increase the burden on family caregivers, community care, and residential care services. Exercise one lifestyle factor identified as a potential means of reducing or delaying progression of the symptoms of dementia.

Study Charateristics

This review evaluated the results of 16 trials (search date August 2012), including 937 participants, that tested whether exercise programs could improve cognition, activities of daily living, behaviour, depression, and mortality in older people with dementia or benefit their family caregivers.

Key Findings

There was promising evidence that exercise programs can significantly improve the cognitive functioning of people with dementia and their ability to perform daily activities, but there was a lot of variation between trial results that we were not able to explain. The studies showed no significant effect of exercise on mood. There was little or no evidence regarding the other outcomes listed above. Further well-designed research is required to examine these outcomes and to determine the best type of exercise program for people with different types and severity of dementia.

Quality of Evidence

Twelve additional trials were included in this updated review compared with the four included in the previous version of the review. As a result the number of participants increased to 937 at baseline and 798 (85.2%) completed the trials, compared with 280 at baseline and 208 (74%) completing the trials in our previous review. These are encouraging results. The number and quality of included trials were sufficient to address the first three objectives relating to the effect of exercise on cognition, ADLs, and depression. However, only one trial was included in the analyses of the effect of exercise on challenging behaviours and caregiver burden, and no analyses were completed for the following outcomes: mortality in people with dementia, caregiver quality of life, caregiver mortality, and use of healthcare services.

The authors have no conflicts of interest.

Résumé simplifié

Les programmes d'exercice physique chez les patients atteints de démence

Contexte

À l'avenir, alors que la population vieillit, le nombre de personnes dans nos communautés souffrant de démence augmentera de façon dramatique. Cela n’affectera pas uniquement la qualité de vie des personnes souffrant de démence, mais augmentera également le fardeau pour la famille et les proches aidants, les soins de proximité et les services de soins à domicile. Un programme d’exercices relié au mode de vie a été identifié comme un moyen potentiel pour réduire ou retarder la progression des symptômes de la démence.

Les caractéristiques de l'étude

Cette revue a évalué les résultats de 16 essais (date de la recherche en août 2012), incluant 937 participants, ayant testé si les programmes d'exercice physique pouvaient améliorer la fonction cognitive, les activités de la vie quotidienne, le comportement, la dépression et la mortalité chez les personnes âgées atteintes de démence ou bénéficier aux proches aidants.

Résultats principaux

Des preuves prometteuses indiquaient que les programmes d'exercices peuvent significativement améliorer le fonctionnement cognitif des personnes atteintes de démence et leur capacité à effectuer les activités quotidiennes, mais il y avait une grande variation entre les résultats des essais que nous n’avons pas été en mesure d'expliquer. Les études n’ont montré aucun effet significatif de l'exercice sur l'humeur. Il n'y avait que peu ou pas de preuves concernant les autres critères de jugement mentionnés ci-dessus. Des recherches supplémentaires et bien conçues sont nécessaires pour examiner ces critères de jugement et pour déterminer le meilleur programme d'exercices pour les personnes souffrant de différents types et gravités de la démence.

Qualité des preuves

Douze essais supplémentaires ont été inclus dans cette revue mise à jour par rapport aux quatre inclus dans la version précédente de la revue. En conséquence, le nombre de participants a augmenté de 937 à l'inclusion et 798 (85,2%) ont été jusqu' à la fin des essais, par rapport à notre revue précédente dans laquelle le nombre de participants était de 280 à l'inclusion et 208 (74%) avaient été jusqu' à la fin des essais. Ces sont des résultats encourageants. Le nombre et la qualité des essais inclus ont été suffisants pour répondre aux trois premiers objectifs concernant l'effet de l'exercice sur la cognition, les activités de la vie quotidienne (AVQ) et la dépression. Cependant, un seul essai a été inclus dans les analyses de l'effet de l'exercice sur les comportements difficiles et le fardeau pour les soignants. De même, aucune analyse n’a été réalisée pour les critères de jugement suivants : la mortalité chez les personnes atteintes de démence, la qualité de vie des soignants, la mortalité des soignants et l'utilisation des services de santé.

Les auteurs n’ont pas de conflit d'intérêt.

Notes de traduction

Traduit par: French Cochrane Centre 14th January, 2014
Traduction financée par: Financeurs pour le Canada : Instituts de Recherche en Santé du Canada, Ministère de la Santé et des Services Sociaux du Québec, Fonds de recherche du Québec-Santé et Institut National d'Excellence en Santé et en Services Sociaux; pour la France : Ministère en charge de la Santé

Laienverständliche Zusammenfassung

Trainingsprogramme für Menschen mit Demenz

Hintergrund

In der Zukunft wird mit zunehmendem Bevölkerungsalter die Zahl der an unter Demenz leidenden Personen in unserer Gesellschaft drastisch steigen. Dies wirkt sich nicht nur auf die Lebensqualität von an Demenz erkrankten Personen aus, sondern erhöht auch die Belastung für deren Betreuer innerhalb der Familie, der häuslichen Pflege und in Pflegeeinrichtungen. Körperliche Aktivität kann Demenz-Symptome nachgewiesenermaßen reduzieren oder ihren Fortschritt verlangsamen.

Studieneigenschaften

Die vorliegende Übersichtsarbeit beurteilte die Ergebnisse von 16 Studien (Suchdatum August 2012) mit insgesamt 937 Teilnehmern. In den eingeschlossenen Studien wurde untersucht, ob sich sportliche Trainingsprogramme positiv auf Wahrnehmung, Alltagsaktivitäten, Verhalten, Depression und Sterblichkeit bei älteren Personen mit Demenz auswirken oder den pflegenden Angehörigen zugutekommen können.

Wichtigste Ergebnisse

Die Resultate der Studien deuten insgesamt darauf hin, dass Trainingsprogramme die kognitiven Funktionen von Personen mit Demenz und ihre Fähigkeit, Aktivitäten des Alltags zu meistern, in statistisch bedeutendem Ausmaß (signifikant) verbessern. Allerdings lag eine hohe Variation zwischen einzelnen Studienergebnissen vor, welche wir nicht erklären konnten. Die Studien zeigten keinen signifikanten Effekt von körperlicher Aktivität auf die Stimmungslage der Teilnehmer. Es gab nur wenige oder keine Belege im Hinblick auf die anderen, oben aufgelisteten Studienergebnisse. Weitere gut konzipierte Forschung ist erforderlich, um diese Studienergebnisse zu untersuchen und um die besten Arten von Trainingsprogrammen für Personen mit verschiedenen Typen und Schweregraden von Demenz zu ermitteln.

Qualität der Ergebnisse

Im Vergleich zu vier eingeschlossenen Studien in der vorherigen Version wurden in diese aktualisierte Übersichtsarbeit zwölf zusätzliche Studien aufgenommen. Dadurch stieg die Zahl der Teilnehmer auf 937 zu Studienbeginn, von denen 798 (85,2 %) die Studie abschlossen, im Vergleich zu 280 Teilnehmern zu Studienbeginn mit 208 (74 %), die die Studie abschlossen, in der Vorversion. Die Ergebnisse sind vielversprechend. Anzahl und Qualität der eingeschlossenen Studien reichten aus, um die ersten drei Ziele, den Einfluss körperlicher Aktivität auf Wahrnehmung, Alltagsaktivitäten und Depression, zu untersuchen. Jedoch konnte nur eine Studie in die Untersuchung zur Wirkung körperlicher Aktivität auf Problemverhalten und Pflegebelastung mit einbezogen werden. Analysen zu den folgenden Studienergebnissen konnten nicht durchgeführt werden: Sterblichkeit bei Patienten mit Demenz, Lebensqualität und Sterblichkeit von Betreuern und Inanspruchnahme von Leistungen des Gesundheitswesens.

Für die Autoren bestehen keine Interessenkonflikte.

Anmerkungen zur Übersetzung

A. Lieder, Koordination durch Cochrane Schweiz

எளியமொழிச் சுருக்கம்

முதுமை மறதி நோய் (டிமென்ஷியா) கொண்ட மக்களுக்கான உடற்பயிற்சி திட்டங்கள்

பின்புலம்

எதிர்காலத்தில், மக்கள் தொகை முதிர்வடையும் போது, நமது சமூகங்களில் டிமென்ஷியாவால் பாதிக்கப்பட்ட மக்களின் எண்ணிக்கை கணிசமான அளவிற்கு உயரும். இது, டிமென்ஷியா கொண்ட மக்களின் வாழ்க்கை தரத்தை பாதிப்பது மட்டுமல்லாது குடும்ப பராமரிப்பாளர்கள், சமூக பராமரிப்பு, மற்றும் குடியிருப்பு பராமரிப்பு சேவைகள் மீதான சுமையை அதிகரிக்கும். டிமென்ஷியா அறிகுறிகளை குறைப்பதற்கு அல்லது அறிகுறிகள் முன்னேற்றத்தை தாமதப்படுத்துவதற்கு வாழ்க்கைமுறையின் ஒரு காரணியாகிய ​ உடற்பயிற்சி ஒரு சாத்தியமான வழிமுறையாக அடையாளம் காணப்படுகிறது.

ஆய்வு பண்புகள்

டிமென்ஷியா கொண்ட முதுமக்களில், உடற்பயிற்சி திட்டங்கள், அறிவாற்றல், அன்றாட வாழ்க்கை நடவடிக்கைகள், நடத்தை, மனச் சோர்வு, மற்றும் இறப்பு விகிதம் ஆகியவற்றை மேம்படுத்த முடியுமா அல்லது அவர்களின் குடும்ப பராமரிப்பாளர்களுக்கு பயனளிக்குமா என்பதை சோதனை செய்த 937, பங்கேற்பாளர்கள் கொண்ட 16 சோதனைகளின் (தேடல் தேதி ஆகஸ்ட் 2012), முடிவுகளை இந்த திறனாய்வு மதிப்பீடு செய்தது.

முக்கிய கண்டுபிடிப்புகள்

உடற்பயிற்சி திட்டங்கள், டிமென்ஷியா கொண்ட மக்களின் மனநல செயல்பாடு மற்றும் அவர்களின் அன்றாட நடவடிக்கைகளை செய்து கொள்ளக் கூடிய திறனை கணிசமாக மேம்படுத்த முடியும் என்பதிற்கு உறுதியுடன் கூடிய சான்று இருந்தது, ஆனால் எங்களால் விளக்க முடியாத நிறைய மாறுபாடு சோதனை முடிவுகளுக்கிடையே இருந்தது. மனநிலை மேல் உடற்பயிற்சியின் குறிப்பிடத்தக்க எந்த விளைவும் இல்லை என்று ஆய்வுகள் காட்டியது. மேலே பட்டியலிடப்பட்டுள்ள பிற விளைவுகள் குறித்து சிறிய அல்லது எந்த ஆதாரமும் இல்லை. இந்த விளைவுகளை ஆராயவும் மற்றும் பல்வேறு வகையான முதுமை மறதி மற்றும் தீவிரத்தன்மை கொண்ட மக்களுக்கு சிறந்த வகை உடற்பயிற்சி திட்டத்தை தீர்மானிக்கவும் இன்னும் கூடுதலான நன்கு-வடிவமைக்கப்பட்ட ஆய்வுகள் தேவைப்படுகிறது.

சான்றின் தரம்

இந்த திறனாய்வின் முந்தைய பதிப்பில் சேர்க்கப்பட்டிருந்த நான்கு சோதனைகளுடன் ஒப்பிடுகையில், இந்த மேம்படுத்தப்பட்ட திறனாய்வில் பன்னிரண்டு கூடுதல் சோதனைகள் சேர்க்கப்பட்டிருந்தன. இதன் விளைவாக, நம் முந்தைய திறனாய்வில் தளநிலை பங்கேற்பாளர்களின் 280 எண்ணிக்கை மற்றும் சோதனைகளை நிறைவு செய்த பங்கேற்பாளர்களின் 208 (74%) எண்ணிக்கையைக் காட்டிலும் தளநிலை பங்கேற்பாளர்களின் எண்ணிக்கை 937 மற்றும் நிறைவு செய்த பங்கேற்பாளர்களின் எண்ணிக்கை 798 (85.2%) என அதிகரித்தது. இவை ஊக்குவிக்கும் முடிவுகளாக உள்ளன. சேர்க்கப்பட்டிருந்த சோதனைகளின் எண்ணிக்கை மற்றும் தரம் ஆகியவை, அறிவாற்றல், அன்றாட நடவடிக்கைகள், மற்றும் மனச் சோர்வு மேல் உடற்பயிற்சியின் விளைவு தொடர்பான முதல் மூன்று இலக்குகளை அறிவுறுத்த போதுமானதாக இருந்தன. எனினும், ஒரே ஒரு சோதனை, சவாலான நடத்தைகள் மற்றும் பராமரிப்பாளர் சுமையின் மேல் உடற்பயிற்சியின் விளைவு பற்றிய பகுப்பாய்வில் சேர்க்கப்பட்டிருந்தது, மற்றும் பின்வரும் விளைவுகளுக்கு எந்த பகுப்பாய்வுகளும் முடிக்கப்படவில்லை: டிமென்ஷியா கொண்ட மக்களில் இறப்பு, பராமரிப்பாளரின் வாழ்க்கைத் தரம், பராமரிப்பாளரின் இறப்பு, மற்றும் ஆரோக்கிய பயன்பாடு சேவைகள்.

ஆசிரியர்களுக்கு எந்தவொரு ஆதாய முரண்பாடுகளும் இல்லை.

மொழிபெயர்ப்பு குறிப்புகள்

மொழி பெயர்ப்பாளர்கள்: சிந்தியா ஸ்வர்ணலதா ஸ்ரீகேசவன், தங்கமணி ராமலிங்கம், ப்ளசிங்டா விஜய், ஸ்ரீகேசவன் சபாபதி.

Background

 

Description of the condition

In 2012, the World Health Organization declared dementia to be a public health priority (World Health Organization 2012), citing the high global prevalence and economic impact on families, communities, and health service providers. In the coming decades, with the aging of the population, the number of individuals living with dementia in our communities will rise dramatically. This will increase the burden on family caregivers, community care, and residential care services (Alzheimer Society of Canada 2010; World Alzheimer Report 2011). People diagnosed with dementia often have unique needs, as they tend to be older and present with acquired impairment in memory, associated with other disturbances of higher cortical function, or personality changes (APA 1995; McKhann 1984). As a first approach, best practice guidelines currently recommend the exploration of behavioural and psychological interventions before initiating pharmacological interventions, due to the limited benefit of pharmacological treatments in reducing functional decline and their potential side effects (Forbes 2008a; Hogan 2008). Exercise is among the potential protective lifestyle factors identified as a strategy for treating the symptoms of dementia or delaying its progression (Lautenschlager 2010).

Description of the intervention

Many studies have examined the influence of exercise on healthy older people. A Cochrane review that included 11 randomized controlled trials (RCTs) of aerobic exercise programs for older people reported that eight studies showed improvement in at least one aspect of cognitive function (Angevaren 2008), with the largest effects on cognitive speed, delayed memory functions, auditory and visual attention. However, the aspects of cognitive function that improved differed across studies, and the majority of comparisons were not significantly different. Since this review, further studies with older people have revealed that exercise improves depression (e.g. Chen 2009); aerobic exercise training increases the size of the anterior hippocampus, with improvements in cognition (Erickson 2011); and mid-life exercise may contribute to maintenance of cognitive function and may reduce or delay the risk of late-life dementia (Chang 2010). A recent narrative review included 12 medium- to high-quality RCTs (Tseng 2011). Five of the studies that focused on healthy adults revealed that exercise can improve cognitive function. Most studies examined used a 60-minute exercise regimen scheduled three times per week that continued for 24 weeks. Hamer 2009 conducted a systematic review that included 16 prospective studies (163,797 participants without dementia at baseline with 3219 with dementia at follow-up). The relative risk (RR) of dementia in the highest exercise category compared with the lowest was 0.72 (95% CI 0.60 to 0.86, P value < 0.001) and for Alzheimer's disease (AD) the RR was 0.55 (95% CI 0.36 to 0.84, P value 0.006). The authors concluded that exercise is inversely associated with risk of dementia. However, Miller 2012 cautioned that, although the association between exercise and preserved cognition during aging was clearly demonstrated, the specific hypothesis - that exercise is a cause of healthy cognitive aging - had yet to be validated. A number of factors could mediate the exercise-cognition association, including depression, and social or cognitive stimulation. These factors need to be studied systematically, including identifying the type of activity most useful to individual participants.

Recent research has also examined the influence of exercise with people with mild cognitive impairment (MCI). Miller 2011 reported no improvement in cognitive function in people with MCI who participated in an exercise program. They concluded that exercise may be beneficial prior to the onset of MCI, but is less beneficial after its onset. A twice-weekly, group-based, moderate-intensity walking program over one year led to no improvement in cognition, except in those with better adherence. For these participants, the walking program was efficacious in improving memory in men, and memory and attention in women (Van Uffelen 2008). However, Intlekofer 2012 suggests that evidence is starting to emerge that exercise supports brain health even when initiated after the appearance of AD pathology. Clearly, further investigation is needed in this area.

How the intervention might work

Physical activity, as defined for this review, refers to "body movement that is produced by the contraction of skeletal muscles and that increases energy expenditure" (Chodzko-Zajko 2009). Exercise refers to "planned, structured, and repetitive movement to improve or maintain one or more components of physical fitness" (Chodzko-Zajko 2009). There are several potential mechanisms that link exercise programs, which include physical activity to cognitive function. A detailed examination of the potential mechanism(s) is beyond the scope of this review. For further information the reader is directed to two recent reviews, Erickson 2012 and Davenport 2012. Briefly, exercise improves vascular health by reducing blood pressure (Fleg 2012), arterial stiffness (Fleg 2012), oxidative stress (Covas 2002), systemic inflammation (Lavie 2011), and enhances endothelial dysfunction (Ghisi 2010), all of which are associated in the maintenance of cerebral perfusion (Churchill 2002; Davenport 2012; Rogers 1990). Recent evidence has shown a strong association between cerebral perfusion (i.e. balance between the supply and demand of nutrients to the brain), cognitive function, and fitness in older healthy adults (Brown 2010). Furthermore, insulin resistance or glucose intolerance is linked with amyloid β plaque formation (Farris 2003; Wareham 2000; Watson 2003), which is a feature of AD. Exercise is known to enhance insulin sensitivity and glucose control (Ryan 2000). Exercise may also preserve neuronal structure and promote neurogenesis, synaptogenesis, and capillarization (formation of nerve cells, the gaps between them, and blood vessels, respectively) (Colcombe 2003), which may be associated with exercise-induced elevation in brain-derived neurotrophic factor (BDNF) (Vaynman 2004), and insulin-like growth factors (Cotman 2007). Animal and human studies investigating the role of BDNF provide evidence that BDNF supports the health and growth of neurons and may regulate neuroplasticity (adaptability of the brain) as we age (Cheng 2003; Vaynman 2004). Intlekofer 2012 recently reported that exercise reinstates hippocampal function by enhancing the expression of BDNF and other growth factors that promote neurogenesis, angiogenesis (formation of blood vessels), and synaptic plasticity. Taken together, animal and human studies indicate that exercise provides a powerful stimulus that can counteract the molecular changes that underlie the progressive loss of hippocampal function in advanced age and AD (Erickson 2012).

Why it is important to do this review

Our initial Cochrane review in 2008 examined the influence of physical activity on people with dementia (Forbes 2008b). It included four RCTs, but only two provided the data necessary for the analysis. We concluded that there was insufficient evidence to draw conclusions about the effectiveness of physical activity programs in improving cognition, function, behaviour, depression, and mortality in people with dementia. Since conducting that review, more RCTs of exercise for dementia have been published, and an update is now timely to determine the effects of exercise programs on these outcomes as well as on burden, health, quality of life and mortality for family caregivers, and cost of healthcare services.

Objectives

Primary:

  • Do exercise programs for older people with dementia improve cognition, activities of daily living (ADLs), challenging behaviour, depression, and mortality in older persons with dementia?

Secondary:

  • Do exercise programs for older people with dementia have an indirect impact on family caregivers’ burden, quality of life, and mortality?

  • Do exercise programs for older people with dementia reduce the use of healthcare services (e.g. visits to the emergency department) by participants and their family caregivers?

Methods

Criteria for considering studies for this review

Types of studies

In this review, we included RCTs in which older people diagnosed with dementia were allocated to either an exercise program or a control group (usual care or social contact/activities). Although parallel group trials were preferred, cross-over trials were eligible, but we only considered data from the first treatment phase (prior to the cross-over). We included non-blinded trials, as it was unrealistic to expect blinding of the participants and those who conducted the exercise programs. We expected outcome assessors to be blinded to treatment allocation, however, we did not exclude studies if blinding of outcome assessors was not incorporated in the study. We rated studies for blinding in the 'Risk of bias' tables.

Types of participants

The majority of participants in the trials had to be older people (over 65 years of age) and diagnosed as having dementia using accepted criteria such as the Diagnostic and Statistical Manual of Mental Disorders ( APA 1995; DSM-III-R, DSM-IV 1994), the National Institute of Neurological and Communicative Disorders and Stroke, and the Alzheimer's Disease and Related Disorders Association (McKhann 1984), ICD-10 (World Health Organization 1992), or CERAD-K (Hwang 2010). 

Types of interventions

Interventions included exercise programs offered over any length of time with the aim of improving cognition, ADLs, behaviour, depression, and mortality in older people with dementia or improving the family caregiver burden, health, quality of life, or to decrease caregiver mortality, or use of healthcare services, or a combination of these. We included trials where the only difference between groups was the exercise intervention, and the types, frequencies, intensities, duration, and settings of the exercise programs were described. The exercise could be any combination of aerobic-, strength-, or balance-training. The comparison groups received either usual care, or social contact/activities, to ensure that the participants received a similar amount of attention.

Types of outcome measures

Primary outcomes

The primary outcomes concerned the person with dementia, and included: cognition, ADLs, challenging behaviour (e.g. agitation, aggression), depression, and mortality.

Secondary outcomes

The secondary outcomes concerned the family caregiver(s), and included burden of care, quality of life, and mortality. We had intended to examine system costs related to use of health services, however, none of the included trials examined use of healthcare services.

Search methods for identification of studies

Electronic searches

We searched ALOIS (www.medicine.ox.ac.uk/alois) - the Cochrane Dementia and Cognitive Improvement Group’s Specialised Register - on 4 September 2011 and again on 14 August 2012. The search terms used were: physical activity OR exercise OR cycling OR swim* OR gym* OR walk* OR danc* OR yoga OR ‘tai chi’.

ALOIS is maintained by the Trials Search Co-ordinator of the Cochrane Dementia and Cognitive Improvement Group and contains studies in the areas of dementia prevention, dementia treatment, and cognitive enhancement in healthy adults. The studies are identified from: 

  1. Monthly searches of a number of major healthcare databases: MEDLINE (Ovid SP), EMBASE (Ovid SP), CINAHL (EBSCOhost), PsycINFO (Ovid SP) and LILACS (BIREME).

  2. Monthly searches of a number of trial registers: ISRCTN; UMIN (Japan's Trial Register); the World Health Organization portal (which covers ClinicalTrials.gov; ISRCTN; the Chinese Clinical Trials Register; the German Clinical Trials Register; the Iranian Registry of Clinical Trials and the Netherlands National Trials Register, plus others).

  3. Quarterly search of The Cochrane Library’s Central Register of Controlled Trials (CENTRAL).

  4. Six-monthly searches of a number of grey literature sources: ISI Web of Knowledge Conference Proceedings; Index to Theses; Australasian Digital Theses.

To view a list of all sources searched for ALOIS see About ALOIS on the ALOIS website.

Details of the search strategies used for the retrieval of reports of trials from the healthcare databases, CENTRAL, and conference proceedings can be viewed in the ‘Methods used in reviews’ section within the editorial information about the Dementia and Cognitive Improvement Group.

We performed additional searches in many of the sources listed above to cover the timeframe from the last searches performed for ALOIS to ensure that the search for the review was as up-to-date and as comprehensive as possible. There was no restriction on language. The search strategies used can be seen in Appendix 1 and Appendix 2.

We performed another search in October 2013. We identified one new study for potential inclusion. We will incoprorate this into the next update of this review.

Data collection and analysis

Selection of studies

After merging search results and discarding duplicates, at least two authors (DF, SCF, ET) independently examined titles and abstracts of citations. If a title or abstract appeared to represent our inclusion criteria, we retrieved the full article for further assessment. At least two authors, one a content expert (SCF) and the others with expertise in conducting systematic reviews (DF, ET), independently assessed the retrieved articles for inclusion in the review according to the eligibility criteria outlined above. We resolved disagreements by discussion, or if necessary, referred to another author. The excluded articles and reasons for exclusion are listed in the ‘Characteristics of excluded studies’ table.

Data extraction and management

We extracted information from the published articles including the study setting, inclusion and exclusion criteria, participants’ diagnosis and level of activity, description of the exercise programs, the randomization process, blinding, drop-out rates, and outcome data.

The mean change from baseline to final measurements and the standard deviation (SD) of the change were often not reported in the published reports. Accordingly, we extracted the final mean measurements, the SD of the final mean, and the number of participants for each group at each assessment. The included trials reported no dichotomous data of interest to this review. One author extracted data from published reports, or requested it from the original first author when necessary, and at least two authors checked this. We resolved disagreements as noted above.

Assessment of risk of bias in included studies

Criteria for judging risk of bias were based on the Cochrane Handbook for Systematic Reviews of Interventions, version 5.1.0, chapter 8 (Higgins 2011). At least two authors, one a content expert (SCF), and the others (DF, ET) with expertise in conducting systematic reviews, independently assessed and rated the trials according to the 'Risk of bias' criteria below. The authors used an assessment tool to determine whether there was a low, high, or unclear risk of bias for each factor (see table 8.5.d, Higgins 2011). The identity of the publication and author information for each trial report was not masked. If the description of a process or outcome was unclear or missing, we contacted the original author of the trial in an attempt to retrieve the required information. Again, we resolved disagreements by discussion, or, if necessary, referred to a third author. We assessed the following criteria:

  1. Selection bias - systematic differences between baseline characteristics of the groups being compared, including:

    1. random sequence generation;

    2. allocation concealment.

  2. Performance bias - systematic differences between groups in the care that is provided, or in exposure to factors other than the interventions of interest, this includes:

    1. blinding of participants and personnel.

  3. Detection bias - systematic differences between groups in how outcomes are determined, this includes:

    1. blinding of outcome assessment.

  4. Attrition bias - systematic differences between groups in withdrawals from a study, this includes:

    1. incomplete outcome data.

  5. Reporting bias - systematic differences between reported and unreported findings, that is:

    1. selective reporting.

  6. Other bias, such as:

    1. bias due to other problems.

Measures of treatment effect

Summary statistics were required for each trial and each outcome. For continuous data, we used the mean difference (MD) when the pooled trials used the same rating scale or test to assess an outcome. We used the standardized mean difference (SMD), which is the absolute mean difference divided by the SD, when the pooled trials used different rating scales or tests. We used the inverse variance method in the meta-analysis. All outcomes were reported using 95% confidence intervals (CI). None of the trials included in the review reported dichotomous data of interest to this review.

Unit of analysis issues

If a cross-over design study was included in the review, we planned to only consider the results prior to the cross-over for inclusion in our analysis. However, we did not have any cross-over design studies to consider. If a trial included three or more arms, consideration was given to the nature of the intervention and control arms. Combining the data from two treatment arms that were similar and had the same control group was undertaken as recommended in the Cochrane Handbook for Systematic Reviews of Interventions, section 7.7.3.8 and Table 7.7a (Higgins 2011). For one trial, (Williams 2008), we pooled two intervention arms (exercise group and a walking group) that were compared with a control (conversation) group.

Dealing with missing data

Many types of information were found to be missing from the published articles, such as descriptions of the process of randomization, blinding of outcome assessors, attrition and adherence to the exercise program, reasons for withdrawing, and statistical data (i.e. means and SDs). We emailed contact authors on at least three separate occasions over a three-month period and requested them to provide the missing data. Some of this missing data is described in the 'Risk of bias' tables. The potential impact of the missing data on the results depended on the extent of missing data, the pooled estimate of the treatment effect, and the variability of the outcomes. Variation in the degree of missing data was also considered as a potential source of heterogeneity. If available, intention-to-treat (ITT) data were used, and, if not available, only the reported completers’ data were used in the analyses.

Assessment of heterogeneity

We considered only trials that demonstrated clinical homogeneity (that is, trials that tested similar exercise programs and examined similar outcome measures) to be potentially appropriate for meta-analysis. Heterogeneity was initially explored through visual exploration of the forest plots. A test for statistical heterogeneity (a consequence of clinical or methodological diversity, or both, among trials) was then performed using the Chi2 test (with a P value < 0.10 indicating significance) and I2 analysis. The I2 analysis is a useful statistic for quantifying inconsistency (I2 = [(Q - df)/Q] x 100%, where Q is the Chi2 statistic and df is its degrees of freedom; Higgins 2002; Higgins 2003). This describes the percentage of variability in effect estimates that is due to heterogeneity rather than sampling error (chance). Values greater than 50% are considered to represent substantial heterogeneity, and, when these occurred, we attempted to explain this variation. If the value was less than 30%, we presented the overall estimate using a fixed-effect model. If, however, there was evidence of heterogeneity of the population or treatment effect, or both, between trials, then we used a random-effects model, for which the confidence intervals are broader than those of a fixed-effect model (Higgins 2011).

Assessment of reporting biases

We explored publication bias through examining funnel plots for signs of asymmetry. We also explored additional reasons for asymmetry. However, only a few studies were included in the meta-analyses, so this approach was not reliable. To investigate reporting biases within our included studies, we compared outcomes listed in the methods sections with reported results.

Data synthesis

As stated above, we conducted the meta-analysis using a fixed-effect model except when the I2 measure of heterogeneity was greater than 30%, when we used a random-effects model in the analyses.

Subgroup analysis and investigation of heterogeneity

It was decided a priori that, if there were sufficient data, we would conduct the following subgroup analyses to explore possible causes of heterogeneity:

Severity of dementia at baseline:

  1. mild - Mini Mental State Examination (MMSE) 17 to 26, or similar scale (Hogan 2007);

  2. moderate (MMSE 10 to 17, or similar scale (Hogan 2007);

  3. severe (MMSE < 10, or similar scale) (Feldman 2005).

Disease type:

  1. AD;

  2. vascular dementia;

  3. mixed dementia;

  4. unclassified or other dementia.

Type of exercise program:

  1. aerobic;

  2. strength;

  3. balance.

Frequency of exercise program:

  1. up to three times per week;

  2. more than three times per week.

Duration of exercise program:

  1. up to 12 weeks;

  2. more than 12 weeks.

Sensitivity analysis

We also considered sensitivity analyses, a priori, to explore possible causes of methodological heterogeneity, such as including studies that used a variety of measurement tools.

Results

Description of studies

Please see ‘Characteristics of included studies’, 'Characteristics of excluded studies’, and ‘Characteristics of ongoing studies’ tables.

Results of the search

Database searches located a total of 3844 articles; the abstracts and titles of 501 of these were screened for inclusion. Fifty-one articles were retrieved and independently rated by two reviewers. Seventeen articles met the inclusion criteria (Christofoletti 2008; Conradsson 2010 (two articles); Eggermont 2009a; Eggermont 2009b; Francese 1997; Hwang 2010; Holliman 2001; Kemoun 2010; Rolland 2007; Santana-Sosa 2008; Steinberg 2009; Stevens 2006; Van de Winckel 2004; Venturelli 2011; Vreugdenhil 2012; Williams 2008). Two of these articles reported on different outcomes from the same trial (Conradsson 2010). Thus, 16 trials were included in the review. See Figure 1 for a flow chart.

Figure 1.

Study flow diagram

Included studies

The included articles were published between 1997 and 2012. Four trials were conducted in the United States (Francese 1997; Holliman 2001; Steinberg 2009; Williams 2008), one in Sweden (Conradsson 2010), two in France (Kemoun 2010; Rolland 2007), two in Australia (Stevens 2006; Vreugdenhil 2012), two in the Netherlands (Eggermont 2009a; Eggermont 2009b), and one each in Belgium (Van de Winckel 2004), Brazil (Christofoletti 2008), Italy (Venturelli 2011), South Korea (Hwang 2010), and Spain (Santana-Sosa 2008).

Participants

Please see 'Characteristics of included studies' table.

Participants were residents of nursing homes (Eggermont 2009a; Eggermont 2009b; Francese 1997; Hwang 2010; Kemoun 2010; Rolland 2007; Santana-Sosa 2008; Stevens 2006; Venturelli 2011; Williams 2008), graduated residential care (Conradsson 2010), psychiatric facilities (Christofoletti 2008; Holliman 2001; Van de Winckel 2004), and in participants’ home settings (Steinberg 2009; Vreugdenhil 2012).

Consent was obtained in all trials from the participants or, from their legal guardian or family member, or both. Three of the included trials recruited fewer than 20 participants: Francese 1997, Holliman 2001, and Santana-Sosa 2008. Nine trials recruited between 24 and 66 participants: Venturelli 2011, Van de Winckel 2004, Steinberg 2009, Hwang 2010, Kemoun 2010, Vreugdenhil 2012, Williams 2008, Christofoletti 2008, and Eggermont 2009b. Four other trials recruited 100 or more participants: Conradsson 2010, Rolland 2007, Stevens 2006, and Eggermont 2009a. The total number of participants who were assessed at baseline was 937, and 798 (84.2%) participants completed the trials.

All but one trial required a diagnosis of dementia for eligibility. Only 52% of participants (100/191) in the Conradsson 2010 trial had a diagnosed dementia disorder, but separate data were available for these participants. Conradsson 2010 and Venturelli 2011 required participants to be 65 years or older. Eggermont 2009a and Eggermont 2009b required participants to be 70 years or older. Three trials had a length of residency or attendance requirement: participants had to have been living in the nursing home for three weeks (Holliman 2001), two months (Rolland 2007), or four months (Santana-Sosa 2008).

The most commonly used diagnostic criteria for dementia in the included studies were from DSM-IV (Conradsson 2010; Eggermont 2009a; Eggermont 2009b; Kemoun 2010; Vreugdenhil 2012). Other authors used the National Institute of Neurological and Communicative Disorders and Stroke, and the Alzheimer Disease and Related Disorders Association (NINCDS-ADRDA) criteria for probable or possible Alzheimer's disease as eligibility for inclusion (Rolland 2007; Santana-Sosa 2008; Steinberg 2009; Van de Winckel 2004; Vreugdenhil 2012; Williams 2008), the International Statistical Classification of Diseases, 10th revision (ICD-10) definition of dementia (Christofoletti 2008), Clinical Dementia Rating (CDR3-CDR4) for late stage AD (Venturelli 2011), Consortium to Establish a Registry for Alzheimer's Disease Assessment Package-Korean (CERAD-K) (Hwang 2010), MMSE (Holliman 2001), chart review (Francese 1997), and a local Aged Care Assessment Team (Stevens 2006).

The majority of trial participants had AD (Eggermont 2009b; Francese 1997; Kemoun 2010; Rolland 2007; Santana-Sosa 2008; Steinberg 2009; Venturelli 2011; Vreugdenhil 2012; Williams 2008). One of the trials had participants with vascular disease and AD (Van de Winckel 2004). In the remaining trials, participants’ type of dementia was unspecified (Christofoletti 2008; Conradsson 2010; Eggermont 2009a; Holliman 2001; Hwang 2010; Stevens 2006).

One of the included trials had participants with mild dementia (Santana-Sosa 2008). Six of the trials had participants with mild to moderate dementia (Conradsson 2010; Eggermont 2009a; Eggermont 2009b; Steinberg 2009; Stevens 2006; Vreugdenhil 2012). Only two of the trials had participants with moderate to severe dementia (Venturelli 2011; Williams 2008). Four of the trials had participants with mild to severe dementia (Hwang 2010; Kemoun 2010; Rolland 2007; Van de Winckel 2004), and two had participants with severe dementia (Francese 1997; Holliman 2001).

Ten of the trials specified the participants’ level of physical abilities: Eggermont 2009a required the ability to walk short distances with no aid; Eggermont 2009b required no apparent disability in hand motor function; Kemoun 2010 required the ability to walk 10 metres without technical assistance; Conradsson 2010 required the ability to stand up from a chair with help from no more than one person; Rolland 2007 required that the residents be able to transfer from a chair and walk six metres without human assistance; Francese 1997 required the residents to need one- to two-person assistance to transfer; Van de Winckel 2004 required the ability to mimic the movements of the therapist and to be able to hear the music; Venturelli 2011 required an absence of mobility limitations; Steinberg 2009 required that participants be ambulatory; and Williams 2008 required that participants be able to walk with assistance, but also that they be dependent in at least one of the following, bed mobility, transfers, gait, or balance. Conradsson 2010 and Venturelli 2011 required participants to be dependent on assistance from a person in one or more personal ADLs. Santana-Sosa 2008 required that participants be free of neurological, vision, muscle or cardio-respiratory disorders, and Christofoletti 2008 required that participants had no other neurological or neuropsychiatric conditions, had no prescriptions of antidepressant medications with central anti-cholinergic or sedative action, and had no drug-related cognitive or balance impairment. Eggermont 2009a and Eggermont 2009b required participants with no visual disturbances, hearing difficulties, history of alcoholism, personality disorders, cerebral trauma, or disturbances of consciousness.

Additional inclusion criteria required participants to have: good general health, a stable medical history and had a caregiver who spent at least 10 hours per week with the participant (Steinberg 2009); a caregiver who either lived with the participant or visited daily (Vreugdenhil 2012); a score of seven or above on the Cornell Scale for Depression in Dementia (CSDD) (Williams 2008); a MMSE score lower than 24/30 (Van de Winckel 2004); a MMSE score from 5 to 15 and a minimum score of 23 on the Performance Oriented Mobility Assessment (POMA) index, with a constant oxygen saturation during walking (SpO2 that exceeded 85%) (Venturelli 2011); discharge scheduled after the trial (Holliman 2001); medical fitness (Christofoletti 2008); physical ability to participate (Francese 1997; Hwang 2010; Stevens 2006); ability to respond to most verbal requests (Stevens 2006; Van de Winckel 2004); and the ability to understand English (Francese 1997). Participants in the Holliman 2001 trial were not permitted to be participants in another, simultaneous research trial.

Exercise programs

The administration of the exercise programs ranged from twice a week (Rolland 2007), to three times a week (Christofoletti 2008; Hwang 2010; Kemoun 2010; Santana-Sosa 2008), four times a week (Venturelli 2011), five times a week (Eggermont 2009a; Eggermont 2009b; Williams 2008), to daily (Van de Winckel 2004; Vreugdenhil 2012). Conradsson 2010 required participants to complete five sessions every two weeks. Steinberg 2009 required the participants in the exercise group to achieve a number of points that were accrued for performing activities in the aerobic, strength, and balance categories (one point for partially performing a task; two for completing). The goal was to achieve six aerobic points and four each of strength and balance per week. Each session varied in length from 20 minutes (Francese 1997), to 30 minutes (Eggermont 2009a; Eggermont 2009b; Holliman 2001; Stevens 2006; Van de Winckel 2004; Venturelli 2011; Vreugdenhil 2012; Williams 2008), 45 minutes (Conradsson 2010), 50 minutes (Hwang 2010), 60 minutes (Christofoletti 2008; Kemoun 2010), up to 75 minutes (Santana-Sosa 2008). The period of time the program was offered varied greatly from two weeks (Holliman 2001), to six weeks (Eggermont 2009a; Eggermont 2009b), seven weeks (Francese 1997), 12 weeks (Santana-Sosa 2008; Stevens 2006; Steinberg 2009; Van de Winckel 2004), 13 weeks (Conradsson 2010); 15 weeks (Kemoun 2010), 16 weeks (Vreugdenhil 2012; Williams 2008), six months (Christofoletti 2008; Venturelli 2011), up to 12 months (Rolland 2007).

In three trials the exercises were performed while seated in order to accommodate people in wheelchairs (Francese 1997; Holliman 2001; Stevens 2006). In the Rolland 2007 trial, the first half hour of the session consisted of walking, and the remainder of the program included strength and balance training. Francese 1997 offered an exercise regime that consisted of activities such as catching, throwing, and kicking balls; leg weight exercises; and parachute reaches. Holliman 2001 designed the exercise program to target the training of gross and fine motor skills and movement, and also to be meaningful and appropriate for the residents. This program included several interactive exercises such as passing a bean bag or playing volleyball in order to promote socialization. The program used by Stevens 2006 was based on joint and large muscle group movement with the intention of creating gentle, aerobic exertion. Christofoletti 2008 and Vreugdenhil 2012 used walking and upper and lower limb exercises to stimulate strength, balance, motor co-ordination, agility, flexibility, and aerobic endurance. The Santana-Sosa 2008 training sessions included joint mobility, resistance, and co-ordination exercises. Hwang 2010 conducted an upper body dance therapy program. Van de Winckel 2004 incorporated upper and lower body strengthening as well as balance, trunk movements, and flexibility training, all supported by music. Participants in Conradsson 2010 performed a high-intensity functional weight-bearing exercise program, including strength and balance exercises. Steinberg 2009 focused on walking, strength training, balance, and flexibility training. Eggermont 2009a and Venturelli 2011 provided a supervised walking program. Participants in Eggermont 2009b performed hand movements only. Williams 2008 compared two experimental interventions: the first combined walking and strength-based exercises focusing on improving strength, balance, and flexibility, while the second consisted of supervised walking.

Control groups

The control groups for eight of the studies received usual care with no additional interventions (Christofoletti 2008; Hwang 2010; Kemoun 2010; Rolland 2007; Santana-Sosa 2008; Stevens 2006; Venturelli 2011; Vreugdenhil 2012). The control group for four studies included social contact (Eggermont 2009a; Steinberg 2009; Van de Winckel 2004; Williams 2008). In three studies the control groups consisted of social contact with additional activities such as films, singing, and reading (Conradsson 2010; Eggermont 2009b; Francese 1997). One study did not provide any details about the control group (Holliman 2001).

Primary outcomes
Cognitive

The MMSE test was used frequently in trials (Christofoletti 2008; Holliman 2001; Steinberg 2009; Van de Winckel 2004; Venturelli 2011; Vreugdenhil 2012). In addition, Hwang 2010 used the Cognitive Memory Performance Scale; Kemoun 2010 used the Rapid Evaluation of Cognition Functions Test; Stevens 2006 measured the progression of dementia with the Clock Drawing Test; while Eggermont 2009a and Eggermont 2009b used a Delayed Recall score using the Eight Words Test. For all these measuring scales, higher scores indicate less cognitive impairment.

Activities of daily living (ADL)

ADL were assessed using the Barthel ADL index (Conradsson 2010; Santana-Sosa 2008; Venturelli 2011; Vreugdenhil 2012), Katz Index of ADLs (Rolland 2007; Santana-Sosa 2008), and Changes in Advanced Dementia Scale (CADS) (Francese 1997). Higher scores in the Barthel ADL Index, Katz Index and the CADS indicate greater ability to perform ADLs.

Challenging behaviours

Four trials measured challenging behaviours of the participants (Holliman 2001; Rolland 2007; Stevens 2006; Van de Winckel 2004). A subscale of the Psychogeriatric Dependency Rating Scale (PGDRS) was used to measure behaviours such as wandering, active aggression and restlessness related to dementia (Holliman 2001). Rolland 2007 evaluated behavioural disturbances as a secondary outcome measure using the Neuropsychiatric Inventory (NPI).Stevens 2006 used the Revised Elderly Disability Scale, which assesses self-help skills, behaviour, and six other categories that reflect functional ability. behaviour was also evaluated with the abbreviated Stockton Geriatric Rating Scale (Van de Winckel 2004). Higher scores on these scales indicate worse or dependent behaviours; all measures are appropriate for people with dementia.

Depression

Depression was evaluated using the Montgomery-Asberg Depression Rating Scale (Rolland 2007), Cornell Scale for Depression in Dementia (CSDD) (Steinberg 2009; Williams 2008), the NPI (Steinberg 2009), and the Geriatric Depression Scale (Conradsson 2010; Eggermont 2009a; Eggermont 2009b; Vreugdenhil 2012). All of these measures are valid, reliable and specific to people with dementia; higher scores indicate greater depression.

Mortality

No included studies measured mortality.

Secondary outcomes
Caregiver burden

Caregiver burden was assessed using the Screen for Caregiver Burden (Steinberg 2009), and the Zarit Burden Interview Scale (Vreugdenhil 2012). In both cases, higher scores indicate increased burden.

Caregiver quality of life

No included studies measured caregiver quality of life.

Caregiver mortality

No included studies measured caregiver mortality.

Use of healthcare services

No included studies measured use of healthcare services.

Excluded studies

Twenty-four trials were excluded for the following reasons: five were not or likely not randomised (Aman 2009; Arcoverde 2008; Batman 1999; Christofoletti 2011; Kwak 2008), nine did not include persons diagnosed with dementia (Anon 1986; Kerse 2008; Littbrand 2006; Netz 1994; Powell 1974; Rodgers 2002; Scherder 2005; van Uffelen 2005; Viscogliosi 2000; two studies included treatments in addition to the exercise (Burgener 2008; Oswald 2007) and one study did not include an exercise program (Onor 2007). One study did not incorporate a comparison group comprised of persons with dementia (Heyn 2008) and another study did not include usual care in the control group (Obisesan 2011). Five studies examined outcomes that were not of interest to this review (Littbrand 2011; Netz 2007; Tappen 2000; Williams 2007; Yagüez 2011).

Risk of bias in included studies

(See Characteristics of included studies.)

Allocation

Random sequence generation (selection bias)

In eleven trials the methods used to generate allocation sequence were not described or were unclear (Christofoletti 2008; Conradsson 2010; Eggermont 2009b; Francese 1997; Holliman 2001; Hwang 2010; Kemoun 2010; Santana-Sosa 2008; Steinberg 2009; Venturelli 2011; Williams 2008). The remaining trials were judged to be at low risk of bias for this domain, as sufficient information about the way the allocation sequence was generated was available (Eggermont 2009a; Rolland 2007; Stevens 2006; Van de Winckel 2004; Vreugdenhil 2012).

Allocation (selection bias)

Methods used to conceal allocation sequence in eleven of the trials were unclear or not described (Eggermont 2009a; Eggermont 2009b; Francese 1997; Holliman 2001; Hwang 2010; Kemoun 2010; Santana-Sosa 2008; Steinberg 2009; Stevens 2006; Van de Winckel 2004; Williams 2008). In the remaining trials, allocation concealment was adequate and, due to this factor, the risk of selection bias was rated as low (Christofoletti 2008; Conradsson 2010; Rolland 2007; Venturelli 2011).

Blinding

Blinding of participants and personnel (performance bias)

All studies were at high risk of performance bias, as blinding of participants and personnel to the intervention was not possible, due to the nature of rehabilitation trials.

Blinding of outcome assessment (detection bias)

Blinding of outcome assessors was not described in Francese 1997, Hwang 2010, and Stevens 2006. Venturelli 2011 stated that the evaluation was completed in a "blinded way" and provided no further explanation, so it was not clear whether outcome assessments had been blinded. The Van de Winckel 2004 study stated, "The physiotherapist who was conducting both treatments evaluated the patients on cognition. However, the nurses who scored the patient on behaviours were all blind to the group assignment.", and so was at high risk for detection bias for cognition outcomes. The remaining trials were at low risk for detection bias since outcome assessors were blinded (Christofoletti 2008; Conradsson 2010; Eggermont 2009a; Eggermont 2009b; Holliman 2001; Kemoun 2010; Rolland 2007; Santana-Sosa 2008; Steinberg 2009; Vreugdenhil 2012; Williams 2008).

Incomplete outcome data

Attrition rates (drop-outs from the trials) varied from 0% to 37% in the included trials. Attrition bias was unclear for Steinberg 2009, since the trial report did not provide data on attrition; we received no response when we requested this information. Stevens 2006 was the only author who did not indicate the group (experimental or control) from which the drop-out occurred. The drop-out rates were higher in the experimental arms for Christofoletti 2008 (29% experimental versus 15% control), Kemoun 2010 (20% experimental versus 17% control), Conradsson 2010 (14% experimental versus 9% control), and Eggermont 2009b (12% experimental versus 3% control). Attrition was higher in the control groups for Francese 1997 (0% experimental versus 17% control), Van de Winckel 2004 (0% experimental versus 10% control), Venturelli 2011 (8% experimental versus 17% control), Rolland 2007 (16% experimental versus 19% control), and Hwang 2010 (29% experimental versus 43% control). Reasons for attrition were provided, and included: death, illness, increased disability, disinterest, physician’s disapproval, withdrawal of consent by family, moving to another institution, and refusal to continue to participate.

In summary, the majority of the trials were rated as having low attrition bias, trials with high attrition used ITT principles in analysis. High attrition bias was reported for five of the included studies for a variety of reasons that included (Christofoletti 2008; Holliman 2001; Hwang 2010; Steinberg 2009; Stevens 2006): failure to report attrition rates for individual groups; a high attrition rate; or an imbalance of attrition between the groups, or failure to provide reasons for attrition, or both (see Characteristics of included studies).

Selective reporting

All of the included trials had low reporting bias, as all outcomes reported were based on the objectives of the study.

Other potential sources of bias

Several points included in the Characteristics of included studies section may be considered to indicate other potential sources of bias, such as attendance and adherence to the exercise programs. Only eight trials provided information regarding the adherence of participants in the intervention arms: Santana-Sosa 2008 (98.9% for five subjects, 97% for three subjects); Venturelli 2011 (93%); Kemoun 2010 (90%); Conradsson 2010 (72%); Steinberg 2009 (59% of the diaries were received and 75% of the exercise group met their goals); Rolland 2007 (mean adherence 33% (SD 25.5) of the 88 sessions offered, although 100% were included in the ITT analysis); Eggermont 2009b (data analysed from residents with 80% attendance or greater); and Stevens 2006 (data analysed from residents with 75% attendance or greater). Figure 2 and Figure 3 provide summaries of risk of bias.

Figure 2.

Risk of bias graph: review authors' judgments about each risk of bias item presented as percentages across all included trials

Figure 3.

Risk of bias summary: review authors' judgments about each risk of bias item for each included trial

Effects of interventions

Primary outcomes

Cognition (eight trials; 329 participants)

We included eight trials that examined the effect of exercise on cognition in the meta-analysis (Christofoletti 2008; Eggermont 2009a; Eggermont 2009b; Hwang 2010; Kemoun 2010; Van de Winckel 2004; Venturelli 2011; Vreugdenhil 2012). We included post-intervention end point measures of means, SDs, and number of participants in each group in the meta-analysis.

A random-effects model was used, as the Chi2 value was 34.67 and the I2 value was 80%, indicating substantial heterogeneity. The meta-analysis yielded significant results (P value 0.04) that favoured the exercise program (k = 8, n = 329; SMD 0.55, 95% CI 0.02 to 1.09) (Analysis 1.1; Figure 4a).

Figure 4.

Forest plot of comparison 1: Physical activity vs usual care: cognition

We explored potential reasons for the high heterogeneity by completing the following meta-analyses that included only trials: 1) with people diagnosed with AD; and 2) that ran the exercise programs for: more than 12 weeks; more than three times per week; less than three times per week; included only aerobic exercise; and included only strength exercise. None of these meta-analyses reduced the heterogeneity. However, when we removed the Venturelli 2011 trial - since it was the only trial that included only participants with moderate to severe dementia - the heterogeneity was reduced (Chi2  value 18.49; I2 value 68%), but the results of this meta-analysis were not significant (P value 0.15; k = 7; n = 308; SMD 0.31, 95% CI -0.11 to 0.74) (Analysis 1.1; Figure 4b).    

Although three additional trials also examined cognition (Holliman 2001; Steinberg 2009; Stevens 2006), they could not be included in the analyses as the necessary data were not reported, and the authors did not provide them upon request. However, their conclusions were mixed: Holliman 2001 and Steinberg 2009 showed no benefit of exercise on cognition, whereas participants in the exercise program in the Stevens 2006 study showed improvement in cognition.

Activities of daily living (ADLs) (six trials; 289 participants)

Six studies measured the effect of exercise on ADLs (Conradsson 2010; Francese 1997; Rolland 2007; Santana-Sosa 2008; Venturelli 2011; Vreugdenhil 2012). We included end point measures of means, SDs, and number of participants in each group in the meta-analysis. A random-effects model was used as the Chi2 value was 22.19 and the I2 value was 77%, indicating considerable heterogeneity. The meta-analysis yielded significant results (P value 0.03), that favoured the exercise program (k = 6; n = 289; SMD 0.68, 95% CI 0.08 to 1.27) (Analysis 2.1; Figure 5).

Figure 5.

Forest plot of comparison 2: Physical activity vs usual care: Activities of daily living (ADLs)

We explored potential reasons for the high heterogeneity and completed the following meta-analyses that included only trials: 1) with participants diagnosed with AD; and 2) that ran the exercise programs for more than 12 weeks; less than 12 weeks; more than three times per week; less than three times per week; a combination of aerobic and strength exercises; and removing the trial with only persons with moderate to severe dementia (Venturelli 2011).  None of these meta-analyses reduced the heterogeneity.

Challenging behaviours (four trials; 110 participants)

Holliman 2001, Rolland 2007, Stevens 2006, and  Van de Winckel 2004 examined the effect of exercise on challenging behaviours.

Holliman 2001 did not provide the SDs when using the PGDRS behaviour scale, but did report that participants showed improved behaviour only during group sessions, and not outside the group. Stevens 2006 did not provide useable data but reported that the participants in the exercise program showed improvement in behaviour. Van de Winckel 2004 also did not provide useable data and reported no significant behavioural effects. The Rolland 2007 study revealed non-significant results (P value 0.75; k = 1; n = 110; MD -0.60, 95% CI -4.22 to 3.02).

Depression (six studies; 341 participants)

Six studies examined the effect of exercise on depression (Conradsson 2010; Eggermont 2009b; Rolland 2007; Steinberg 2009; Vreugdenhil 2012; Williams 2008). The trial authors of Steinberg 2009 did not report the data needed for the analysis, or respond to requests for this data. Williams 2008 included two experimental groups: a supervised individual walking group and a comprehensive individual exercise group. We combined the data from the two experimental groups resulting in a sample size of 33, a mean of 9.01 and an SD of 6.11. The meta-analysis revealed a Chi2 value of 1.87 and an I2 value of 0%, indicating no heterogeneity. Consequently, a fixed-effect model was utilized that revealed non-significant results (P value 0.20; k =5; n = 341; MD –0.14, 95% CI -0.36 to 0.07) (Analysis 3.1; Figure 6). As there was no heterogeneity, no subgroup or sensitivity analyses were needed.

Figure 6.

Forest plot of comparison 3: Physical activity vs usual care: depression

Mortality

No trials reported on mortality in people with dementia.

Secondary outcomes

Caregiver burden (two trials; 40 participants)

Two trials examined caregiver burden (Steinberg 2009; Vreugdenhil 2012). As noted above, Steinberg 2009 did not report the data needed for the analysis and the trial authors did not respond to requests for this data. The community-based exercise program in Vreugdenhil 2012 revealed a significant improvement in caregiver burden (P value 0.001). The fixed-effect model revealed significant results (k = 1; n = 40; MD -15.30, 95% CI -24.73 to -5.87).

Caregiver quality of life

No studies reported on caregivers’ quality of life.

Caregiver mortality

No studies reported on caregivers’ mortality.

Use of healthcare services

No studies reported on use of healthcare services.

Adverse events (five trials)

Five studies addressed potential adverse events of exercise programs for people with dementia (Conradsson 2010; Rolland 2007; Santana-Sosa 2008; Steinberg 2009; Venturelli 2011). None of these trials revealed any serious adverse events that could be attributed to the exercise intervention. One trial, Christofoletti 2008, indirectly addressed adverse events by stating there were no drop-outs related to the treatment.

Discussion

Summary of main results

This review included 16 trials (17 articles) with a total of 937 participants. Most participants were older people with AD. The exercise programs varied greatly; the length of time that they ran ranged from two weeks to 12 months, and activities varied (e.g. hand movements, sitting, walking, and upper and lower limb exercises). The review suggests that exercise programs may have a significant impact on improving cognitive functioning and the ability to perform ADLs in people with dementia. There was substantial and considerable unexplained statistical heterogeneity observed in the cognitive and ADL analyses, respectively, which suggests the need for caution in interpreting these results. Indeed, when we removed the Venturelli 2011 trial from the cognitive analysis - since it was the only trial that included only people with moderate to severe dementia - the heterogeneity was reduced, and the results of this meta-analysis were no longer significant. In addition, our findings reveal that the burden experienced by informal caregivers providing care in the home may be reduced if they supervise their family member with dementia during participation in an exercise program. This review found no significant effect of exercise on challenging behaviours or depression. Nevertheless, these are encouraging results, as dementia is a debilitating disease that results in progressive decline in cognition and ability to perform ADLs, as well as other symptoms. A slowing of both cognitive decline and the development of dependence in ADLs is critical for enhancing the quality of life for people with dementia, and will have an impact on the family caregivers’ ability to sustain their caregiving role.

Overall completeness and applicability of evidence

The number of included trials was sufficient to address the first three objectives relating to the effect of exercise on cognition, ADLs, and depression. However, only one trial was included in the analyses of the effect on challenging behaviours and caregiver burden, and no analyses were completed for the following outcomes: mortality in people with dementia, caregiver quality of life, caregiver mortality, and use of healthcare services. Although several additional included trials investigated cognition (four trials), challenging behaviours (three trials), depression (two trials), and caregiver burden (one trial), useable data for inclusion in the meta-analyses were not provided by the authors. It is important to include means and SDs for end point measures, or change from baseline to final measurement scores in published reports, or the authors should be willing to provide these data on request. Clearly, additional research is needed that examines these important outcomes and provides the needed data for meta-analysis.

Only two studies were based in the community (Steinberg 2009; Vreugdenhil 2012), all others were conducted in institutions. Most people with dementia are cared for at home, and most caregivers wish to keep the family member with dementia at home for as long as possible. Knowing how to support family caregivers and delay the symptoms of dementia will have profound benefits for all involved. In addition, enabling people with dementia to remain in their homes for longer will lead to decreased healthcare costs. Further community-based trials are needed that examine the effect of exercise on multiple domains of the person with dementia and the impact on their family caregivers.

The participants within the trials were not homogeneous in terms of their diagnosis (e.g. AD, vascular dementia, mixed dementia, other) or severity of dementia (e.g. mild, moderate, severe). This was unfortunate, as dementia should not be viewed as a single disease entity, and there is preliminary evidence that exercise might affect the risk of these conditions differently (Rockwood 2007). Several observational studies have found that the preventive effects of exercise may be weaker for vascular dementia than for AD or dementia in general (Rockwood 2007). However, a more recent meta-analysis (Aarsland 2010) revealed a significant association between exercise and a reduced risk of developing vascular dementia (odds ratio 0.62, 95% CI 0.42 to 0.92).

Also, the exercise programs were not homogeneous in terms of the type (e.g. aerobic, strength, balance), duration (range: two weeks to 12 months), and frequency (range: two times per week to daily) of activities. Therefore, further subgroup analyses compared type, duration (less than 12 weeks versus longer than 12 weeks), and frequency (less than three times per week versus more than three times per week) of the exercise programs. However, because of the few number of trials included in the review it was not possible to determine a dose-response between the type, duration, or frequency of exercise, and the degree of protection from cognitive decline and other outcomes.

Quality of the evidence

Twelve additional trials were included in this updated review compared with the four included in the previous version of the review. As a result the number of participants increased to 937 at baseline and 798 (85.2%) completed the trials, compared with 280 at baseline and 208 (74%) completing the trials in our previous review. These are encouraging results. However, many of the authors of the trials did not report the random sequence generation and allocation concealment processes adequately. A computer-generated program managed by a third party is a rigorous approach that can be used to generate random allocation to groups, and ensures allocation concealment. Several authors did not report or did not describe adequately the outcome data for each main outcome. Although blinding of the participants and individuals conducting the exercise programs was not possible, it was expected that outcome assessors would be blinded. A few authors failed to report on the blinding of outcome assessors. High attrition rates, an imbalance of attrition between groups, and unknown reasons for attrition and poor adherence (or no description) to the exercise programs were also potential sources of bias in several of the included trials. In addition, some trials with high attrition rates did not conduct ITT analysis (see Figure 2 and Figure 3).

Potential biases in the review process

This review was conducted as outlined in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011), therefore, the introduction of bias during the review process was minimized. We are fairly confident that all relevant studies were identified, as the literature searches were conducted by Anna Noel-Storr of the Cochrane Dementia and Cognitive Improvement Group and are updated at least every six months. However, not all of the included trials reported data that could be used in the meta-analysis, and some authors did not respond to requests for this data. Thus, the results of four trials could not be included in our meta-analyses. This was unfortunate as the total number of trials that have examined the effectiveness of exercise programs for improving the symptoms of dementia is limited.

Agreements and disagreements with other studies or reviews

A recent systematic review, that included 13 RCTs with 896 participants (Potter 2011), found similar, non-significant, results to those identified in this review for depression; only one of the four trials identified by Potter et al that reported depression as an outcome found a positive effect. However, Thune-Boyle 2012, who used a critical interpretive approach to synthesize the literature, concluded that exercise appears to be beneficial in reducing depressed mood. The Potter 2011 review reported on two trials that found an improvement in quality of life; our review did not include any trials that examined quality of life, and only one trial that examined challenging behaviours. Thus, we concur with Thune-Boyle 2012 that the evidence is weak or lacking for an effect of exercise on challenging behaviours, such as repetitive behaviours, and also with Potter 2011 that the evidence for an effect on depression and quality of life is limited. We would agree with both authors that further research is needed that examines depression, quality of life, and challenging behaviours.

Authors' conclusions

Implications for practice

With an increased number of trials now available, there is evidence that suggests that exercise programs could have a significant impact on improving cognitive functioning and ability to perform activities of daily living (ADLs) in people with dementia. Healthcare providers who work with people with dementia and their caregivers should feel confident in promoting exercise among this population, as decreasing the progression of cognitive decline and dependence in ADLs will have significant benefits for people with dementia and their family caregivers’ quality of life, and possibly delay the need for placement in long-term care settings. No trials reported adverse events related to exercise programs.

One trial that examined the burden experienced by family caregivers who provide care in the home revealed that this burden can be reduced if they supervise their family member with dementia during participation in an exercise program. Therefore, encouraging caregivers to participate in exercise may also have a beneficial impact on their quality of life.  

Setting (home versus institutional) can be considered in the future, if more studies become available. There was an insufficient number of trials to permit subgroup analyses that would determine which type of exercise (aerobic, strength training, balance), at what frequency and duration, is most beneficial for specific types and severity of dementia. Clearly further research is needed to be able to develop best practice guidelines that would be helpful to healthcare providers in advising people with dementia living in institutional and community settings.

Implications for research

For older people in general, recent research recommends at least 150 minutes of moderate- to vigorous-intensity aerobic exercise per week, in bouts of 10 minutes or more to achieve better quality of life, improve functional abilities, and reduce risk of disease, death, and loss of independence by up to 60%. In addition, muscle and bone strengthening activities using major muscle groups, at least two times per week is recommended (Chodzko-Zajko 2009; Tremblay 2011). Other research has revealed that aerobic-type exercise has a clear benefit over strength training, and moderate-intensity exercise of at least one hour a day, three to five times or more a week may be more effective in improving cognition (Kramer 2007; Middleton 2007).

However, these recommendations may not be appropriate for people with dementia. Further research is necessary to identify the optimal exercise modalities particularly in terms of frequency, intensity, and duration for people with different types and severity of dementia and to identify barriers and facilitators to improving adherence. Attempting to match the exercise programs with the needs, capabilities, and preferences of people with dementia, and ensuring adequate funding to provide regular, appropriate programs, over extended periods, by qualified instructors may increase adherence (Forbes 2007). Additional well designed trials that are conducted in the community setting, which is where most people with dementia live, and that examine outcomes of relevance to people with dementia (e.g. cognition, ADLs, depression, challenging behaviours, and mortality), family caregiver outcomes (e.g. caregiver burden, quality of life, and mortality) and economic analysis of visits to emergency departments, acute care settings, and cost of residential care are also needed.

No serious adverse events were attributed to participation in the trials. Recent research suggests that high-intensity weight-bearing exercise does not seem to have a negative effect on functional balance (Conradsson 2010). However, further research is needed about potential adverse events from aerobic exercise programs to determine whether this population is similar to older adults in general who are less likely to fall and less likely to injure themselves from falls if they are physically active (Kannus 2005; Sherrington 2004), or if the risk of falling and of cardiovascular events is higher in people with dementia during aerobic exercise.

Clinical researchers should make a practice of ensuring that their trials are of high methodological quality and provide information on the randomization process (sequence generation and allocation concealment), blinding of outcome assessors, attrition rates and reasons for drop-outs from both treatment and control groups, rate of adherence to the exercise programs and reasons for withdrawal, and adverse events to the exercise programs in published articles, or be willing to share this information with reviewers when contacted. Providing statistically appropriate data (e.g. end point means and standard deviations) would also ensure that the trial results can be incorporated into meta-analysis.

Acknowledgements

We wish to thank Anna Noel-Storr, Cochrane Dementia and Cognitive Improvement Group, for conducting the literature searches, and Sue Marcus, Cochrane Dementia and Cognitive Improvement Group, for her assistance throughout the review. We also wish to thank the following authors who contributed to our previous review: Debra Morgan, Maureen Markle-Reid, Jennifer Wood, and Ivan Culum. 

Data and analyses

Download statistical data

Comparison 1. Exercise vs usual care: cognition
Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size
1 Cognition8 Std. Mean Difference (IV, Random, 95% CI)Subtotals only
1.1 Cognition: all trials8329Std. Mean Difference (IV, Random, 95% CI)0.55 [0.02, 1.09]
1.2 Cognition: excluded moderate-severe dementia7308Std. Mean Difference (IV, Random, 95% CI)0.31 [-0.11, 0.74]
Analysis 1.1.

Comparison 1 Exercise vs usual care: cognition, Outcome 1 Cognition.

Comparison 2. Exercise vs usual care: Activities of Daily Living (ADL)
Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size
1 Comparison of ADL6289Std. Mean Difference (IV, Random, 95% CI)0.68 [0.08, 1.27]
1.1 ADL: all trials6289Std. Mean Difference (IV, Random, 95% CI)0.68 [0.08, 1.27]
Analysis 2.1.

Comparison 2 Exercise vs usual care: Activities of Daily Living (ADL), Outcome 1 Comparison of ADL.

Comparison 3. Exercise vs usual care: depression
Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size
1 Depression5341Std. Mean Difference (IV, Random, 95% CI)0.14 [-0.07, 0.36]
Analysis 3.1.

Comparison 3 Exercise vs usual care: depression, Outcome 1 Depression.

Appendices

Appendix 1. Top-up update searches: August 2012 and October 2013

Source

 

Search strategy - date limits are for the August 2012 search (appropriate limits were applied to the October 2013 search)Hits retrieved
1. ALOIS (www.medicine.ox.ac.uk/alois)"physical activity" OR exercise OR cycling OR swim* OR gym* OR walk* OR danc* OR yoga OR "tai chi" (all dates)

August 2012: 225

October 2013: 8

2. MEDLINE In-process and other non-indexed citations and MEDLINE 1950-present (Ovid SP)

 

1. exp Dementia/

2. Delirium/

3. Wernicke Encephalopathy/

4. Delirium, Dementia, Amnestic, Cognitive Disorders/

5. dement*.mp.

6. alzheimer*.mp.

7. (lewy* adj2 bod*).mp.

8. deliri*.mp.

9. (chronic adj2 cerebrovascular).mp.

10. ("organic brain disease" or "organic brain syndrome").mp.

11. ("normal pressure hydrocephalus" and "shunt*").mp.

12. "benign senescent forgetfulness".mp.

13. (cerebr* adj2 deteriorat*).mp.

14. (cerebral* adj2 insufficient*).mp.

15. (pick* adj2 disease).mp.

16. (creutzfeldt or jcd or cjd).mp.

17. huntington*.mp.

18. binswanger*.mp.

19. korsako*.mp.

20. or/1-19

21. exercis*.ti,ab.

22. physical activit*.ti,ab.

23. cycling.ti,ab.

24. swim*.ti,ab.

25. gym*.ti,ab.

26. (walk* or treadmill).ti,ab.

27. danc*.ti,ab.

28. yoga*.ti,ab.

29. "tai chi".ti,ab.

30. exp Exercise/ or Exercise Therapy/

31. or/21-30

32. 20 and 31

33. randomized controlled trial.pt.

34. controlled clinical trial.pt.

35. randomi?ed.ab.

36. placebo.ab.

37. randomly.ab.

38. trial.ab.

39. groups.ab.

40. or/33-39

41. (animals not (humans and animals)).sh.

42. 40 not 41

43. 32 and 42

44. (2011* or 2012*).ed.

45. 43 and 44

 

August 2012: 97

October 2013: 93

3. EMBASE

1980-2012 August 10 (Ovid SP)

1. exp dementia/

2. Lewy body/

3. delirium/

4. Wernicke encephalopathy/

5. cognitive defect/

6. dement*.mp.

7. alzheimer*.mp.

8. (lewy* adj2 bod*).mp.

9. deliri*.mp.

10. (chronic adj2 cerebrovascular).mp.

11. ("organic brain disease" or "organic brain syndrome").mp.

12. "supranuclear palsy".mp.

13. ("normal pressure hydrocephalus" and "shunt*").mp.

14. "benign senescent forgetfulness".mp.

15. (cerebr* adj2 deteriorat*).mp.

16. (cerebral* adj2 insufficient*).mp.

17. (pick* adj2 disease).mp.

18. (creutzfeldt or jcd or cjd).mp.

19. huntington*.mp.

20. binswanger*.mp.

21. korsako*.mp.

22. CADASIL.mp.

23. or/1-22

24. exercis*.ti,ab.

25. physical activit*.ti,ab.

26. cycling.ti,ab.

27. swim*.ti,ab.

28. gym*.ti,ab.

29. (walk* or treadmill).ti,ab.

30. danc*.ti,ab.

31. yoga*.ti,ab.

32. "tai chi".ti,ab.

33. exercise/ or stretching exercise/ or anaerobic exercise/ or exercise intensity/ or aerobic exercise/ or treadmill exercise/ or aquatic exercise/

34. or/24-33

35. 23 and 34

36. randomized controlled trial/

37. controlled clinical trial/

38. randomi?ed.ab.

39. placebo.ab.

40. randomly.ab.

41. trial.ab.

42. groups.ab.

43. ("double-blind*" or "single-blind*").ti,ab.

44. or/36-43

45. 35 and 44

46. (2011* or 2012*).em.

47. 45 and 46

 

August 2012: 307

October 2013: 519

4. PsycINFO

1806-August week 1 2012 (Ovid SP)

1. exp Dementia/

2. exp Delirium/

3. exp Huntingtons Disease/

4. exp Kluver Bucy Syndrome/

5. exp Wernickes Syndrome/

6. exp Cognitive Impairment/

7. dement*.mp.

8. alzheimer*.mp.

9. (lewy* adj2 bod*).mp.

10. deliri*.mp.

11. (chronic adj2 cerebrovascular).mp.

12. ("organic brain disease" or "organic brain syndrome").mp.

13. "supranuclear palsy".mp.

14. ("normal pressure hydrocephalus" and "shunt*").mp.

15. "benign senescent forgetfulness".mp.

16. (cerebr* adj2 deteriorat*).mp.

17. (cerebral* adj2 insufficient*).mp.

18. (pick* adj2 disease).mp.

19. (creutzfeldt or jcd or cjd).mp.

20. huntington*.mp.

21. binswanger*.mp.

22. korsako*.mp.

23. ("parkinson* disease dementia" or PDD or "parkinson* dementia").mp.

24. or/1-23

25. exercis*.ti,ab.

26. physical activit*.ti,ab.

27. cycling.ti,ab.

28. swim*.ti,ab.

29. gym*.ti,ab.

30. (walk* or treadmill).ti,ab.

31. danc*.ti,ab.

32. yoga*.ti,ab.

33. "tai chi".ti,ab.

34. exp Exercise/ or exp Aerobic Exercise/

35. or/25-34

36. 24 and 35

37. random*.ti,ab.

38. exp Clinical Trials/

39. RCT.ti,ab.

40. CCT.ti,ab.

41. (placebo or "control group").ab.

42. trial.ti,ab.

43. groups.ab.

44. "double-blind*".ti,ab.

45. "single-blind*".ti,ab.

46. or/37-45

47. 36 and 46

48. (2011* or 2012*).up.

49. 47 and 48

 

August 2012: 97

October 2013: 118

5. CINAHL (EBSCOhost)

S1 (MH "Dementia+")  

S2 (MH "Delirium") or (MH "Delirium, Dementia, Amnestic, Cognitive Disorders")

S3 (MH "Wernicke's Encephalopathy")  

S4 TX dement*  

S5 TX alzheimer* 

S6 TX lewy* N2 bod*  

S7 TX deliri* 

S8 TX chronic N2 cerebrovascular  

S9 TX "organic brain disease" or "organic brain syndrome"  

S10 TX "normal pressure hydrocephalus" and "shunt*"  

S11 TX "benign senescent forgetfulness" 

S12 TX cerebr* N2 deteriorat* 

S13 TX cerebral* N2 insufficient*  

S14 TX pick* N2 disease

S15 TX creutzfeldt or jcd or cjd  

S16 TX huntington* 

S17 TX binswanger*  

S18 TX korsako* 

S19 S1 or S2 or S3 or S4 or S5 or S6 or S7 or S8 or S9 or S10 or S11 or S12 or S13 or S14 or S15 or S16 or S17 or S18

S20 TX exercis*

S21 TX "physical activit*" 

S22 TX cycling 

S23 TX swim*

S24 TX gym*

S25 TX walk* OR treadmill 

S26 TX danc*

S27 TX yoga*

S28 TX "tai chi" 

S29 (MH "Exercise+") 

S30 S20 or S21 or S22 or S23 or S24 or S25 or S26 or S27 or S28 or S29

S31 S19 and S30 

S32 (MH "Clinical Trials") 

S33 TX trial 

S34 TX RCT OR CCT 

S35 TX placebo*

S36 TX "double-blind*" OR "single-blind*" 

S37 TX groups OR "control group" 

S38 S32 or S33 or S34 or S35 or S36 or S37 

S39 S31 and S38 

S40 EM 2011

S41 EM 2012

S42 S40 OR S41

S43 S42 AND S39

 

August 2012: 101

October 2013: 107

6. ISI Web of Knowledge [includes: Web of Science (1945-present); BIOSIS Previews (1926-present); MEDLINE (1950-present); Journal Citation Reports]

Topic=(Dement* OR Alzheimer* OR "Lewy body" OR arteriosclerosis OR "Huntington* disease" OR "Kluver Bucy" OR "Pick disease" OR "Wernicke encephalopathy" OR "Korsakoff psychosis") AND Topic=(exercis* OR walk* OR swim* OR "physical activit*" OR aerobic* OR danc* OR "tai chi" OR yoga*) AND Topic=(randomly OR placebo OR groups OR trial OR RCT OR randomized OR randomised) AND Year Published=(2011-2012)

Timespan=All Years.

Search language=English   Lemmatization=On  

 

August 2012: 389

October 2013: 404

7. LILACS (BIREME)dementia OR alzheimer$ OR demenc$ OR AD OR demência [Words] and exercício OR exercis$ OR walk$ OR swim$ OR aerobic$ [Words] and randomly OR randomised OR randomized OR trial OR ensaio clínico [Words]

August 2012: 11

October 2013: 5

8. CENTRAL (Issue 4, Dec 2011)

#1 MeSH descriptor Dementia explode all trees

#2 MeSH descriptor Delirium, this term only

#3 MeSH descriptor Wernicke Encephalopathy, this term only

#4 MeSH descriptor Delirium, Dementia, Amnestic, Cognitive Disorders, this term only

#5 dement*

#6 alzheimer*

#7 "lewy* bod*"

#8 deliri*

#9 "chronic cerebrovascular"

#10 "organic brain disease" or "organic brain syndrome"

#11 "normal pressure hydrocephalus" and "shunt*"

#12 "benign senescent forgetfulness"

#13 "cerebr* deteriorat*"

#14 "cerebral* insufficient*"

#15 "pick* disease"

#16 creutzfeldt or jcd or cjd

#17 huntington*

#18 binswanger*

#19 korsako*

#20 (#1 OR #2 OR #3 OR #4 OR #5 OR #6 OR #7 OR #8 OR #9 OR #10 OR #11 OR #12 OR #13 OR #14 OR #15 OR #16 OR #17 OR #18 OR #19)

#21 MeSH descriptor Exercise explode all trees

#22 exercis*

#23 "physical activit*"

#24 cycling

#25 swim*

#26 gym*

#27 walk* OR treadmill

#28 danc*

#29 yoga*

#30 "tai chi"

#31 aerobic*

#32 (#21 OR #22 OR #23 OR #24 OR #25 OR #26 OR #27 OR #28 OR #29 OR #30 OR #31)

#33 (#32 AND #20), from 2011 to 2012 [Trials]

August 2012: 40

October 2013: 123

9. Clinicaltrials.gov (www.clinicaltrials.gov)Interventional Studies | dementia OR alzheimers OR AD OR alzheimer's OR alzheimer OR lewy OR FTLD OR FLD | exercise OR aerobic OR aerobics OR walking OR swimming OR cycling | Adult, Senior | received from 09/01/2011 to 08/13/2012

August 2012: 13

October 2013: 19

10. ICTRP Search Portal (http://apps.who.int/trialsearch) [includes: Australian New Zealand Clinical Trials Registry; ClinicalTrilas.gov; ISRCTN; Chinese Clinical Trial Registry; Clinical Trials Registry – India; Clinical Research Information Service – Republic of Korea; German Clinical Trials Register; Iranian Registry of Clinical Trials; Japan Primary Registries Network; Pan African Clinical Trial Registry; Sri Lanka Clinical Trials Registry; The Netherlands National Trial Register]Interventional Studies | dementia OR alzheimers OR AD OR alzheimer's OR alzheimer OR lewy OR FTLD OR FLD | exercise OR aerobic OR aerobics OR walking OR swimming OR cycling | received from 01/09/2011 to 13/08/2012

August 2012: 50

October 2013: 1

TOTAL before de-duplication

August 2012: 1330

October 2013: 1397

TOTAL after de-duplication

August 2012: 87

October 2013: 41

Appendix 2. Update search: September 2011

Source

 

Search strategyHits retrieved
1. ALOIS (www.medicine.ox.ac.uk/alois)Keyword search: "physical activity" OR exercise cycling OR swim* OR gym* OR walk* OR danc* OR yoga OR "tai chi" (all dates)217
2. MEDLINE In-process and other non-indexed citations and MEDLINE 1950-present (Ovid SP)

1. exp Dementia/

2. Delirium/

3. Wernicke Encephalopathy/

4. Delirium, Dementia, Amnestic, Cognitive Disorders/

5. dement*.mp.

6. alzheimer*.mp.

7. (lewy* adj2 bod*).mp.

8. deliri*.mp.

9. (chronic adj2 cerebrovascular).mp.

10. ("organic brain disease" or "organic brain syndrome").mp.

11. ("normal pressure hydrocephalus" and "shunt*").mp.

12. "benign senescent forgetfulness".mp.

13. (cerebr* adj2 deteriorat*).mp.

14. (cerebral* adj2 insufficient*).mp.

15. (pick* adj2 disease).mp.

16. (creutzfeldt or jcd or cjd).mp.

17. huntington*.mp.

18. binswanger*.mp.

19. korsako*.mp.

20. or/1-19

21. exercis*.ti,ab.

22. physical activit*.ti,ab.

23. cycling.ti,ab.

24. swim*.ti,ab.

25. gym*.ti,ab.

26. (walk* or treadmill).ti,ab.

27. danc*.ti,ab.

28. yoga*.ti,ab.

29. "tai chi".ti,ab.

30. exp Exercise/ or Exercise Therapy/

31. or/21-30

32. 20 and 31

33. randomized controlled trial.pt.

34. controlled clinical trial.pt.

35. randomi?ed.ab.

36. placebo.ab.

37. randomly.ab.

38. trial.ab.

39. groups.ab.

40. or/33-39

41. (animals not (humans and animals)).sh.

42. 40 not 41

43. 32 and 42

44. (2007* or 2008* or 2009* or 2010* or 2011*).ed.

45. 43 and 44

 

230

3. EMBASE

1980-2011 week 35 (Ovid SP)

1. exp dementia/

2. Lewy body/

3. delirium/

4. Wernicke encephalopathy/

5. cognitive defect/

6. dement*.mp.

7. alzheimer*.mp.

8. (lewy* adj2 bod*).mp.

9. deliri*.mp.

10. (chronic adj2 cerebrovascular).mp.

11. ("organic brain disease" or "organic brain syndrome").mp.

12. "supranuclear palsy".mp.

13. ("normal pressure hydrocephalus" and "shunt*").mp.

14. "benign senescent forgetfulness".mp.

15. (cerebr* adj2 deteriorat*).mp.

16. (cerebral* adj2 insufficient*).mp.

17. (pick* adj2 disease).mp.

18. (creutzfeldt or jcd or cjd).mp.

19. huntington*.mp.

20. binswanger*.mp.

21. korsako*.mp.

22. CADASIL.mp.

23. or/1-22

24. exercis*.ti,ab.

25. physical activit*.ti,ab.

26. cycling.ti,ab.

27. swim*.ti,ab.

28. gym*.ti,ab.

29. (walk* or treadmill).ti,ab.

30. danc*.ti,ab.

31. yoga*.ti,ab.

32. "tai chi".ti,ab.

33. exercise/ or stretching exercise/ or anaerobic exercise/ or exercise intensity/ or aerobic exercise/ or treadmill exercise/ or aquatic exercise/

34. or/24-33

35. 23 and 34

36. randomized controlled trial/

37. controlled clinical trial/

38. randomi?ed.ab.

39. placebo.ab.

40. randomly.ab.

41. trial.ab.

42. groups.ab.

43. ("double-blind*" or "single-blind*").ti,ab.

44. or/36-43

45. 35 and 44

46. (2007* or 2008* or 2009* or 2010* or 2011*).em.

47. 45 and 46

48. limit 47 to human

 

443

4. PsycINFO

1806-August week 5 2011 (Ovid SP)

1. exp Dementia/

2. exp Delirium/

3. exp Huntingtons Disease/

4. exp Kluver Bucy Syndrome/

5. exp Wernickes Syndrome/

6. exp Cognitive Impairment/

7. dement*.mp.

8. alzheimer*.mp.

9. (lewy* adj2 bod*).mp.

10. deliri*.mp.

11. (chronic adj2 cerebrovascular).mp.

12. ("organic brain disease" or "organic brain syndrome").mp.

13. "supranuclear palsy".mp.

14. ("normal pressure hydrocephalus" and "shunt*").mp.

15. "benign senescent forgetfulness".mp.

16. (cerebr* adj2 deteriorat*).mp.

17. (cerebral* adj2 insufficient*).mp.

18. (pick* adj2 disease).mp.

19. (creutzfeldt or jcd or cjd).mp.

20. huntington*.mp.

21. binswanger*.mp.

22. korsako*.mp.

23. ("parkinson* disease dementia" or PDD or "parkinson* dementia").mp.

24. or/1-23

25. exercis*.ti,ab.

26. physical activit*.ti,ab.

27. cycling.ti,ab.

28. swim*.ti,ab.

29. gym*.ti,ab.

30. (walk* or treadmill).ti,ab.

31. danc*.ti,ab.

32. yoga*.ti,ab.

33. "tai chi".ti,ab.

34. exp Exercise/ or exp Aerobic Exercise/

35. or/25-34

36. 24 and 35

37. random*.ti,ab.

38. exp Clinical Trials/

39. RCT.ti,ab.

40. CCT.ti,ab.

41. (placebo or "control group").ab.

42. trial.ti,ab.

43. groups.ab.

44. "double-blind*".ti,ab.

45. "single-blind*".ti,ab.

46. or/37-45

47. 36 and 46

48. (2007* or 2008* or 2009* or 2010* or 2011*).up.

49. 47 and 48

 

214
5. CINAHL (EBSCOhost)

S1 (MH "Dementia+")  

S2 (MH "Delirium") or (MH "Delirium, Dementia, Amnestic, Cognitive Disorders")

S3 (MH "Wernicke's Encephalopathy")  

S4 TX dement*  

S5 TX alzheimer* 

S6 TX lewy* N2 bod*  

S7 TX deliri* 

S8 TX chronic N2 cerebrovascular  

S9 TX "organic brain disease" or "organic brain syndrome"  

S10 TX "normal pressure hydrocephalus" and "shunt*"  

S11 TX "benign senescent forgetfulness" 

S12 TX cerebr* N2 deteriorat* 

S13 TX cerebral* N2 insufficient*  

S14 TX pick* N2 disease

S15 TX creutzfeldt or jcd or cjd  

S16 TX huntington* 

S17 TX binswanger*  

S18 TX korsako* 

S19 S1 or S2 or S3 or S4 or S5 or S6 or S7 or S8 or S9 or S10 or S11 or S12 or S13 or S14 or S15 or S16 or S17 or S18

S20 TX exercis*

S21 TX "physical activit*" 

S22 TX cycling 

S23 TX swim*

S24 TX gym*

S25 TX walk* OR treadmill 

S26 TX danc*

S27 TX yoga*

S28 TX "tai chi" 

S29 (MH "Exercise+") 

S30 S20 or S21 or S22 or S23 or S24 or S25 or S26 or S27 or S28 or S29

S31 S19 and S30 

S32 (MH "Clinical Trials") 

S33 TX trial 

S34 TX RCT OR CCT 

S35 TX placebo*

S36 TX "double-blind*" OR "single-blind*" 

S37 TX groups OR "control group" 

S38 S32 or S33 or S34 or S35 or S36 or S37 

S39 S31 and S38 

S40 EM 2007 

S41 EM 2008 

S42 EM 2009 

S43 EM 2010 

S44 EM 2011 

S45 S40 or S41 or S42 or S43 or S44

S46 S39 and S45 

 

264
6. ISI Web of Knowledge [includes: Web of Science (1945-present); BIOSIS Previews (1926-present); MEDLINE (1950-present); Journal Citation Reports]

Topic=(Dement* OR Alzheimer* OR "Lewy body" OR arteriosclerosis OR "Huntington* disease" OR "Kluver Bucy" OR "Pick disease" OR "Wernicke encephalopathy" OR "Korsakoff psychosis") AND Topic=(exercis* OR walk* OR swim* OR "physical activit*" OR aerobic* OR danc* OR "tai chi" OR yoga*) AND Topic=(randomly OR placebo OR groups OR trial OR RCT OR randomized OR randomised) AND Year Published=(2007-2011)

Timespan=2007-2011.

Search language=English   Lemmatization=On

 

641
7. LILACS (BIREME)dementia OR alzheimer$ OR demenc$ OR AD OR demência [Words] and exercício OR exercis$ OR walk$ OR swim$ OR aerobic$ [Words] and randomly OR randomised OR randomized OR trial OR ensaio clínico [Words]9
8. CENTRAL (Issue 2, 2011)

#1 MeSH descriptor Dementia explode all trees

#2 MeSH descriptor Delirium, this term only

#3 MeSH descriptor Wernicke Encephalopathy, this term only

#4 MeSH descriptor Delirium, Dementia, Amnestic, Cognitive Disorders, this term only

#5 dement*

#6 alzheimer*

#7 "lewy* bod*"

#8 deliri*

#9 "chronic cerebrovascular"

#10 "organic brain disease" or "organic brain syndrome"

#11 "normal pressure hydrocephalus" and "shunt*"

#12 "benign senescent forgetfulness"

#13 "cerebr* deteriorat*"

#14 "cerebral* insufficient*"

#15 "pick* disease"

#16 creutzfeldt or jcd or cjd

#17 huntington*

#18 binswanger*

#19 korsako*

#20 (#1 OR #2 OR #3 OR #4 OR #5 OR #6 OR #7 OR #8 OR #9 OR #10 OR #11 OR #12 OR #13 OR #14 OR #15 OR #16 OR #17 OR #18 OR #19)

#21 MeSH descriptor Exercise explode all trees

#22 exercis*

#23 "physical activit*"

#24 cycling

#25 swim*

#26 gym*

#27 walk* OR treadmill

#28 danc*

#29 yoga*

#30 "tai chi"

#31 aerobic*

#32 (#21 OR #22 OR #23 OR #24 OR #25 OR #26 OR #27 OR #28 OR #29 OR #30 OR #31)

#33 (#32 AND #20), from 2007 to 2011

189
9. Clinicaltrials.gov (www.clinicaltrials.gov)Interventional Studies | dementia OR alzheimers OR AD OR alzheimer's OR alzheimer OR lewy OR FTLD OR FLD | exercise OR aerobic OR aerobics OR walking OR swimming OR cycling | Adult, Senior | received from 09/01/2007 to 09/05/201129
10. ICTRP Search Portal (http://apps.who.int/trialsearch) [includes: Australian New Zealand Clinical Trials Registry; ClinicalTrilas.gov; ISRCTN; Chinese Clinical Trial Registry; Clinical Trials Registry – India; Clinical Research Information Service – Republic of Korea; German Clinical Trials Register; Iranian Registry of Clinical Trials; Japan Primary Registries Network; Pan African Clinical Trial Registry; Sri Lanka Clinical Trials Registry; The Netherlands National Trial Register]Interventional Studies | dementia OR alzheimers OR AD OR alzheimer's OR alzheimer OR lewy OR FTLD OR FLD | exercise OR aerobic OR aerobics OR walking OR swimming OR cycling | Adult, Senior | received from 01/09/2007 to 05/09/201195
TOTAL before de-duplication2331
TOTAL after de-duplication and first-assessment277

What's new

Last assessed as up-to-date: 13 August 2012.

DateEventDescription
13 August 2012New citation required and conclusions have changedAn update search was performed for this review on 13 August 2012. The results from this search have been incorporated into the review.The results and conclusions have changed; the review authors have changed.
13 August 2012New search has been performedAn update search was performed for this review on 13 August 2012.

History

Protocol first published: Issue 2, 2007
Review first published: Issue 3, 2008

DateEventDescription
4 September 2011New search has been performedAn update search was performed for this review on 4 September 2011. The results from this search have been incorporated into the review.
28 May 2008AmendedIn additional Table 1: Description of Rating Scales Used in the Included Studies, the abbreviation for Psychogeriatric Dependency Rating Scale has been changed to PGDRS from PGSRS
14 December 2007New citation required and conclusions have changedSubstantive amendment

Contributions of authors

Dorothy Forbes: conceived, designed, and co-ordinated the review
Catherine Blake: corresponded with trial authors, staff at the Cochrane Dementia and Cognitive Improvement Group and team members
Dorothy Forbes, Emily Thiessen, Scott Forbes (SCF): selected trials
Dorothy Forbes, Emily Thiessen, Catherine Blake: assessed risk of bias
Dorothy Forbes, Emily Thiessen, Catherine Blake, Scott Forbes, Sean Forbes (SF): extracted data, analysed data, drafted review versions, and reviewed final submission

Declarations of interest

Dorothy Forbes: none known
Emily Thiessen: none known
Catherine Blake: none known
Scott Forbes: none known
Sean Forbes: none known

Sources of support

Internal sources

  • University of Alberta, Canada.

  • University of Western Ontario, Canada.

  • University of Florida, USA.

External sources

  • Canadian Cochrane Centre, Canada.

    Sponsored Emily Thiessen's attendance at a five day Cochrane Review workshop

  • Nova Scotia Cochrane Centre, Canada.

    Hosted Cochrane Review workshop

Characteristics of studies

Characteristics of included studies [ordered by study ID]

Christofoletti 2008

Methods6-month RCT
Participants

Country: Brazil

Centre: long-term psychiatric institution

Diagnosis: moderate stage mixed dementia

Participants: 54 at baseline, and 41 completed

Baseline: 54 (37 women and 17 men), mean age (SD) = 74.3 years (1.4), mean years of education (SD) = 4.8 (0.7)

Three groups: Group 1 was an interdisciplinary program, group 2 was physiotherapy, group 3 was control. Of the two experimental groups, only group 2 was included in this review.

Experimental Group:  n = 17, mean MMSE (SD)  = 12.7 (2.1)

Control Group: n = 20, mean MMSE (SD)  = 14.6 (1.2)

Inclusion criteria: "primary diagnosis of dementia" using ICD-10 criteria and confirmed by MMSE and Katz ADL score, medically fit for participation in intervention, resident of psychiatric institution

Exclusion criteria: cognitive impairment associated with other neuropsychiatric conditions or neurological diagnosis; antidepressant prescriptions with sedative or anticholinergic actions; impairment of cognition or balance related to drugs

Interventions

Experimental Group: physiotherapy kinesiotherapeutic exercises (strength, balance, memory, and recognition exercise using balls, elastic ribbons, and proprioceptive plates), provided by physiotherapist

Type of physical activity: strength, balance

Frequency: 3 times a week, exercise duration = 1 h

Time period: 6 months

Control Group: received usual care

Time period: 6 months

Outcomes

Cognition outcomes:

1.      Mini-Mental State Examination

2.      Brief Cognitive Screening Battery

NotesThe participants' medications were kept the same throughout the study. If a change in medication was required the participant was removed from the study
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskUnclear process of randomization: "A sealed envelope with an identification number was assigned to each subject, each one filled with a slip giving the group. When a patient was registered and given a number, the appropriate envelope was opened"
Allocation concealment (selection bias)Low riskSealed envelope used, but did not specify whether envelopes were opaque or non-opaque
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated: "As a common bias presented on most rehabilitation trials, it was not possible to 'blind' the subjects regarding the treatments"
Blinding of outcome assessment (detection bias)
All outcomes
Low riskOutcome assessors were blinded
Incomplete outcome data (attrition bias)
All outcomes
High risk

Study attrition rate was 24.1%

Attrition rate for each group:

Experimental Group: 29.4%

Control Group: 15.0%

 

Reasons for attrition given, however, not specified according to group

Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskAttendance and adherence not stated

Conradsson 2010

Methods6-month cluster-RCT
Participants

Note: Conradsson 2010 and Littbrand 2009 articles report on the same trial. Conradsson 2010 reports on depression and Littbrand 2009 reports on ADL

Country: Sweden

Multicentre: 9 residential facilities

Diagnosis: 100 of 191 participants diagnosed with mild to moderate dementia (type of dementia unspecified)

Participants: 191 (139 women and 52 men), mean age (SD) = 84.7 years (6.5), mean MMSE (SD) = 17.8 (5.1).  Baseline age, education, and MMSE, not reported for dementia subgroup

Of the 100 participants with dementia, 91 completed

Experimental Group: n = 47; Control Group: n = 53

Inclusion criteria: 65 years or older, MMSE score ≥ 10, dependent for assistance with at least 1 ADL as per Katz index, able to stand from arm chair with help from no more than 1 person, resident physician approval

Exclusion criteria: none stated

Interventions

Experimental Group: the high-intensity group exercise (3-9 participants per exercise group) focused on weight bearing and progressively increased in difficulty. Activity consisted of strength and balance exercises including walking, squats and trunk exercises

Type of physical activity: strength, balance, aerobic

Frequency: 5 sessions every 2 weeks, exercise duration = 45 minutes

Time period: 13 weeks

Control Group: social contact plus seated activities provided by occupational therapists, e.g. watching films, singing, reading, conversation

Frequency: 5 sessions every 2 weeks, activity duration = 45 minutes

Time period: 13 weeks

Outcomes

Depression outcome (Conradsson 2010): Geriatric Depression Scale 15-item

Psychological well-being outcome (Conradsson 2010): Philadelphia Geriatric Centre Morale Scale

Activity of Daily Living outcome (Littbrand 2009): Barthel ADL Index

NotesWe used only data specific to people with dementia in the analysis
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskProcess of random selection not described
Allocation concealment (selection bias)Low risk"Researchers not involved in this study performed the randomization using lots in sealed non-transparent envelopes" Conradsson 2010
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low risk"The assessors of the outcome measures were blinded to group allocation and previous test results" Conradsson 2010.
Incomplete outcome data (attrition bias)
All outcomes
Low riskThe attrition rate for the Experimental Group was 14.3%, and that of the Control Group 9.0%. Trial authors specified reasons for attrition in each group. ITT principles used in analyses
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Eggermont 2009a

Methods12-week RCT
Participants

Country: Netherlands

Multicentre: 23 nursing homes

Diagnosis: mild to moderate dementia (type of dementia not specified)

Participants: 103* (79 women and 18 men), mean age (SD)  = 85.4 years, mean MMSE (SD)  = 17.7. Information about level of education not provided

* 6 did not complete study protocol so number who actually took part in the study = 97

Experimental Group: n = 51; Control Group: n = 46

Inclusion criteria: age > 70 years; diagnosis of dementia; able to walk for short distances with or without a walking aid; written consent from participants and relatives

Exclusion criteria: MMSE score of < 10 or > 24; visual disturbances; hearing difficulties; history of alcoholism; personality disorders; cerebral trauma; hydrocephalus; neoplasm; or disturbances of consciousness

Interventions

Experimental Group: walking group, walks occurred on unit wards and in public places

Frequency: 5 days a week, exercise duration = 30 minutes

Type of physical activity: aerobic

Time period: 6 weeks

Control Group: social contact

Frequency: 5 days a week, social visit duration = 30 minutes

Time period: 6 weeks

Outcomes

Executive function, memory and cognitive domains outcomes:

1. Rivermead Behavioural Memory Test

2. Wechsler Memory Scale-revised

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Low risk"By tossing a coin subjects were randomly allocated to either an experimental or control group."
Allocation concealment (selection bias)Unclear riskNot described
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low riskOutcome measures were evaluated by a trained psychology student blinded to the participants’ intervention
Incomplete outcome data (attrition bias)
All outcomes
Low riskStudy attrition rate 5.8%. Trial authors did not report group attrition rates, or reasons for attrition. ITT used in analysis
Selective reporting (reporting bias)Low riskUsed 2 rating scales to measure executive function, memory, and cognitive domains.  Components of both scales were reported elsewhere: "The following tests were administered (details are published elsewhere)"
Other biasLow riskAttendance and adherence not stated

Eggermont 2009b

Methods6-week clustered-RCT
Participants

Country: Netherlands

Multicentre: 10 nursing homes

Diagnosis: mild to moderate dementia (subtype unknown), diagnosed with dementia using the DSMIV criteria

Participants: 66 at baseline, and 61 completed; mean age = 84.6 years;

Experimental Group: n = 30, mean MMSE (SD) = 15.8 (5.0); Control Group: n = 31, mean MMSE (SD): 84.2 (4.6)

Interventions

Experimental Group: hand movement activity group performing activities such as "finger movement, pinching a soft ball, or handling a rubber ring"

Type of physical activity: hand movement

Frequency: 5 days a week, duration = 30 minutes

Time period: 6 weeks

Control Group; social contact plus read out loud program

Frequency: 5 days a week, duration = 30 minutes

Time period: 6 weeks

Outcomes

Cognition: MMSE (at baseline)

Memory: examined using the face recognition test from the Rivermead Behavioural Memory Test and the Eight Word Test

Executive function: tested using the stop signal task, attention network test, and the digit span subset from the Weschsler Memory Scale-Revised

Mood: examined using the Geriatric Depression Scale (a Dutch version)

Actigraphy data: rest and activity domain

All outcomes were measured at baseline, after 6 weeks and 12 weeks

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskUnclear process of randomization
Allocation concealment (selection bias)Unclear riskUnclear process of allocation concealment
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants or personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low riskOutcome assessors were blinded
Incomplete outcome data (attrition bias)
All outcomes
Low risk

Reasons for attrition provided

Used ITT analysis

Per-protocol analysis included participants that attend 80% of the sessions

Selective reporting (reporting bias)Low riskReported all outcomes measured
Other biasLow riskNone apparent

Francese 1997

Methods7-week RCT
Participants

Country: USA

Centre: long-term care facility

Diagnosis: severe AD

Participants: 12 participants at baseline, and 11 completed

Completed: 11 (gender not specified), age, years of education, and baseline MMSE not provided

Experimental Group: n = 6; Control Group: n = 5

Inclusion criteria: documentation in chart of late stage Alzheimer-type dementia, could understand English, considered medically fit, require assistance from 1 or 2 care providers to transfer, informed consent obtained by family member or legal guardian

Exclusion criteria: none stated

Interventions

Experimental Group: exercises targeting strength and function that included the use of music, various types of exercise balls and parachute leg weights; participants provided with snack

Type of physical activity: strength, balance

Frequency: 3 times a week, duration = 20 minutes

Time period: 7 weeks

Control Group: social contact plus sing-along group that watched music videos; participants provided with snack.

Frequency: 3 times a week, duration of social activity = 20 minutes

Time period: 7 weeks

Outcomes

Function (particularly ADL) outcomes

Changes in Advanced Dementia Scale

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskMethods of randomization not described
Allocation concealment (selection bias)Unclear riskMethods used to conceal allocation not described
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Unclear riskBlinding of the outcome assessors not described
Incomplete outcome data (attrition bias)
All outcomes
Low riskStudy attrition was 8%, one participant dropped out of Control Group as "had a major CVA and was confined to bed" p 125 Francese, 1997
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskAttendance and adherence not stated

Holliman 2001

Methods2-week, quasi-experimental design
Participants

Country: USA

Centre: geriatric psychiatric facility

Diagnosis: dementia

Participants: 14 at baseline, and 12 completed

- 14 (12 women and 2 men), age range: 65-89 years, education: 1-16 years, mean MMSE (SD) = 4.57 (4.88).

Number of participants in Experimental Group and Control Group not specified

Inclusion criteria:  primary diagnosis of dementia, living with in psychiatric facility for at least 3 weeks, not scheduled to be discharged until after study completed

Exclusion criteria: participating in another research trial at same time

All participants were pronounced to be a danger to themselves or others

Interventions

Experimental Group: activity targeted gross and fine motor skills, and movement in a way that was meaningful and appropriate for participants. Snack provided

Type of physical activity: aerobic and balance

Frequency: 3 times per week, duration = 30 minutes

Time period: 2 weeks

Control Group: activities not described

Outcomes

Behaviour outcomes:

1. Psychogeriatric Dependency Rating Scale

2. Patient Behaviour Rating Sheet (PBRS). (PBRS measure used in the Experimental Group only)

Notes

The following statement was made In the published article, "the sample was not fully randomly assigned due to patient availability, informed consent matters, and institutional procedures" (p 67). Email messages clarified the process of randomization. "Randomly assigned eligible residents a number. In order to assign each resident to either the control or treatment group, copies of these numbers were made and put into an envelope and the numbers were then drawn from the envelope" (personal communication on 5 June 2007 and 5 July 2007)

All exercises completed while sitting in chair, as majority of the participants in wheelchairs

Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskNumbers used, but review authors unaware of where they originated
Allocation concealment (selection bias)Unclear riskUsed envelopes
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low riskOutcome assessors were blinded to group allocation
Incomplete outcome data (attrition bias)
All outcomes
High riskAttrition rate was 14.29% and "all participants were active almost all the time". Reason for attrition provided, but unclear within which group the attrition occurred
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow risk

Attendance and adherence not stated

Control group activity not described

Hwang 2010

Methods8-week trial with random assignment to experiment and control groups
Participants

Country: Korea

Centre: nursing home

Diagnosis: mild-severe dementia (type of dementia unspecified)

Participants: 28 at baseline, and 18 completed

Baseline: 28 (all women)

Experimental Group: n = 14; mean age =  81.30 years (5.4); mean education years (SD) = 3.3 (0.95); mean MMSE-KC (SD) = 11.6 (3.47)

Control Group: n = 14, mean age (SD) = 81.75 years (8.86), mean education years (SD) = 3.0 (1.07), mean MMSE-KC (SD) = 13.88 (5.06)

Inclusion criteria: aged 65 or older, from nursing home residence; agreement of family; recommended by head of facility; dementia confirmed by MMSE-KC score, based on age, years of schooling, and gender; and capable of taking part in intervention activity

Exclusion criteria: none stated

Interventions

Experimental Group: a dance program consisting mainly of upper body exercises, with a 10-minute warm-up and warm-down.

Type of physical activity: strength, balance

Frequency: 3 times a week, duration = 50 minutes

Time period: 8 weeks

Control Group: usual care

OutcomesCognitive outcome: Cognitive Memory Performance Measuring Tool in the Korean version (CERAD-K)
Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskRandomization process not described. Emailed 13 March 2012, 10 April 2012 and 9 May 2012 to clarify randomization, no response received
Allocation concealment (selection bias)Unclear riskNo description of methods used to conceal allocation
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Unclear riskBlinding of outcome assessors not described
Incomplete outcome data (attrition bias)
All outcomes
High risk

Attrition rate: study = 35.7%: Experimental Group = 28.6%; Control Group = 42.9%

Reason for attrition: "10 subjects quit due to personal affairs and health issues, and the materials that were used for the final analysis were those of 18 subjects in total".  Contacted by email for details 10 April 2012 and 9 May 2012, but no response received

Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskAttendance and adherence not stated. The Control Group activity was not described, and participants were recommended by head of facility

Kemoun 2010

Methods19-week RCT
Participants

Country: France

Centre: nursing home

Diagnosis: mild to severe AD

Participants: 38 at baseline, and 31 completed (23 women and 8 men)

Experimental Group: n = 20, mean age (SD) = 82.0 years (5.8), mean MMSE (SD) = 12.6 (range = 7-20)

Control Group: n = 18, mean age (SD) = 81.7 years (5.1), mean MMSE = 12.9

Information about education level of participants not provided

Inclusion criteria: diagnosis of Alzheimer dementia using DSM IV criteria, MMSE < 23, able to walk 10 m without technical assistance

Exclusion criteria: none stated

Interventions

Experimental Group: the exercise program included three different sessions each week, i.e. 1) walking, 2) stamina exercise and 3) a combination of walking, stamina, and balance exercises. For the first 2 weeks of the program participants prepared for the routine program with specific muscles and joint exercises

Type of physical exercise: aerobic, balance

Frequency: 3 times a week, duration = 1 h

Time period: 15 weeks

Control Group: usual care

OutcomesCognition outcome: Rapid Evaluation of Cognitive Functions test (ERFC, French Version)
Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskRandomization process not described.  Email correspondence, Kemoun, 13 May 2012, description was as follows "The process of randomization was conducted by the randomization manager of the clinical investigation centre of the university hospital of Poitiers.  Each randomization number was given for each patient after he had been included in the study by the principal investigator."
Allocation concealment (selection bias)Unclear risk"Subjects were randomized into two groups using a permutation table".  Methods used to conceal allocation not described
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low riskOutcome assessor blinded
Incomplete outcome data (attrition bias)
All outcomes
High riskAttrition rate was 18.4%: 4 participants lost from Experimental Group and 3 from Control Group. Reasons for attrition provided
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Rolland 2007

Methods12-month RCT, 2-week enrolment, single-blinded
Participants

Country: France

Multicentre: 5 nursing homes

Diagnosis: mild to severe AD

Participants: 134 at baseline, and 110 completed

Baseline: 134 (101 women and 33 men), mean age (SD) = 83 years (7.4); mean ADL = 3.1 (1.3); mean MMSE (SD) = 8.8 (6.6)

Experimental Group: n = 67; mean age (SD) = 82.8 years (7.8); mean ADL = 3.2 (1.3); mean MMSE (SD) = 9.7 (6.8)

Control Group: n = 67; mean age (SD) = 83.1 years (7.0); mean ADL (SD) = 3.1 (1.3); mean MMSE (SD) = 7.9 (6.4)

Inclusion criteria: diagnosis in chart of AD or MMSE < 25, diagnosis of AD confirmed by trained geriatrician, met criteria for Alzheimer Disease of National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association, had resided in nursing home for at least 2 months, could transfer from chair and walk 6 m without assistance from people

Exclusion criteria: evidence of Parkinson’s disease or vascular dementia, life expectancy < 6 months due to terminal illness, cardiac condition that could worsen with exercise, planned transfer from nursing home for surgery within the next year

Interventions

Experimental Group: aerobic (walking), strength (lower extremity), flexibility and balance training, gradually increased in intensity, (2-7 participants per group). Music with sessions

Type of physical activity: aerobic, strength, balance

Frequency: 2 times per week, duration = 1 h

Time period: 1 year

Control Group: usual care

Outcomes

ADL outcome: Katz Index of ADLs

Behaviour disturbance outcome: Neuropsychiatric Inventory

Depression outcome: Montgomery-Asberg Depression Rating Scale

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Low riskUsed lottery draw
Allocation concealment (selection bias)Low riskPublished in Forbes 2007
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low riskGeriatrician outcome assessor was blinded to group allocation, data analysts also blinded
Incomplete outcome data (attrition bias)
All outcomes
Low riskAttrition rate of 18%, however 100% were included in ITT analysis (Forbes 2007); reasons for attrition provided
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Santana-Sosa 2008

Methods12-week randomized, block-controlled design
Participants

Country: Spain

Centre: nursing home

Diagnosis: mild AD

Participants: 16 at baseline, all of whom completed

- 16 (10 women and 6 men); information about mean education level not provided

Experimental Group: n = 8; mean age (SD) = 76 years (4); mean MMSE (SD) = 20.1 (2.3)

Control Group: n = 8; mean age (SD) = 73 years (4); mean MMSE (SD) = 19.9 (1.7)

Inclusion criteria: consent of closest relative and geriatrician; diagnosis of AD by geriatrician; MMSE between 18-23 in Spanish validated MMSE; resided in nursing home for at least 4 months

Exclusion criteria: vision, muscle, cardio-respiratory, or neurological disorder (other than AD)

Interventions

Experimental Group: individualized exercise with walking, stretching, joint mobility, resistance and co-ordination exercises (with music)

Type of physical activity: aerobic, strength

Frequency: 3 times a week, duration = 75 minutes

Time period: 12 weeks

Control Group: usual care

OutcomesADL outcome: Katz ADL score, Barthel ADL index
Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskRandomly assigned with a block design according to gender. Email correspondence 10 May 2012 with Alejandro Lucia: "Participants were randomly assigned to either the control or training group with a block on gender based on a randomization sequence."
Allocation concealment (selection bias)Unclear riskMethods used to conceal allocation not described
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low riskOutcome measure assessors blinded
Incomplete outcome data (attrition bias)
All outcomes
Low risk100% of participants completed the trial. Adherence to trained program averaged at 98.8%
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Steinberg 2009

Methods12-week randomly-assigned experimental trial
Participants

Country: USA

Location: home

Diagnosis: mild to moderate AD

Participants: 27 at baseline (19 women and 8 men) all of whom completed; information about education level not provided

Experimental Group: n = 14; mean age (SD) = 76.5 years (3.9); mean MMSE (SD) = 20.1 (5.1)

Control Group: n = 13; mean age (SD) = 74.0 years (8.1); mean MMSE (SD) = 15.5 (5.4)

Inclusion criteria: probable AlD using Alzheimer Disease of National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association criteria; MMSE ≥ 10; residing in community; stable health and medical history; caregiver that was spending a minimum of 10 hours per week with the person with AD.

Exclusion criteria: residing in assisted-living facility

Interventions

Experimental Group: exercise program consisting of aerobic, strength, balance, and flexibility training

Type of physical activity: aerobic, strength, balance

Frequency: daily, exercise duration not specified. Participants were given points for each activity performed. The weekly exercise goal was obtained when the participant collected 6 aerobic points, and 4 strength and balance points

Time period: 12 weeks

Control Group: social contact, e.g. received home safety assessment that included 2 home visits. In addition, participants recorded 3 activities they performed regularly at home

Outcomes

Cognition outcome: 1-h cognitive battery that included the Boston Naming Test, MMSE, and Hopkins Verbal Learning Test

Depression outcomes:

1. Neuropsychiatric Inventory

2. Cornell Scale for Depression in Dementia

Caregiver Burden outcome: Screen for Caregiver Burden

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskStratified randomization by age and gender.  Emailed 13 March 2012, 10 April 2012, and 9 May 2012, to clarify randomization, but no answer received
Allocation concealment (selection bias)Unclear riskNo description of methods used to conceal allocation
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low risk"All tests were administered by the same rater, who was masked as to treatment assignment"
Incomplete outcome data (attrition bias)
All outcomes
Unclear riskAttrition not reported. Requested attrition data 13 March 2012, 10 April 2012, 9 May 2012, and 3 July 2012, but data not provided
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Stevens 2006

Methods12 week, pre- and post-test RCT
Participants

Country: Australia

Multicentre:  6 aged-care facilities, nursing homes

Diagnosis: mild to moderate dementia (type of dementia not specified)

Participants: 120 at baseline, and 75 completed

Completed: 75 (56 women and 19 men), mean age = 80.5 years; mean MMSE not provided

Three groups: Group 1 received no intervention, group 2 received a social visit, and group 3 was the exercise program. Of the two control groups, only group 1 was included in this review.

Experimental Group: n = 24, mean age = 79 years

Control Group: n = 30, mean age = 81 years

Inclusion criteria:  mild to moderate dementia as assessed by local Aged Care Assessment Team; those with confirmed diagnosis of dementia, or MMSE < 23 were considered to have dementia; lived in aged-care facility; capable of providing informed consent legally and competently, or consent obtained from legal guardian; able to respond verbally and appropriately to majority of questions; assessed by Age Care Facility as being physically able to complete exercise

Exclusion criteria:  severe dementia with MMSE of 0-9

Interventions

Experimental Group: activity was based on joint and large muscle group movement with the intention of creating gentle aerobic exertion

Type of physical activity: aerobic

Frequency: 3 times per week, duration = 30 minutes

Time period: 3 months

Control Group: usual care

Outcomes

Behaviour outcome: Revised Elderly Persons Disability Scale

Cognitive Symptoms outcome: Clock-drawing test

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Low riskLottery method
Allocation concealment (selection bias)Unclear riskSimply stated that subjects were randomly allocated by a lottery method
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Unclear riskUnclear whether outcome assessors blinded to group allocation
Incomplete outcome data (attrition bias)
All outcomes
High riskAttrition rate was 37.5%; reason(s) for attrition not provided
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Van de Winckel 2004

Methods3-month RCT
Participants

Country: Belgium

Centre: public psychiatric hospital

Diagnosis: moderate to severe multiple infarct dementia (3 participants) and Alzheimer's disease (22 participants)

Participants: 25 at baseline, and 24 completed

Baseline: 25 (all women)

Experimental Group: n = 15; mean age (SD) = 81.33 years (4.24); mean MMSE (SD) = 12.87 (5.01)

Control Group: n = 10 mean age (SD)  = 81.90 years (4.18); mean MMSE (SD) = 10.8 (5.01)

Inclusion criteria: diagnosed with probable AD using NINCDS-ARDRA criteria or multiple infarct dementia; MMSE < 24; able to follow verbal and visual commands; mimic movements; and hear music. Medically cleared by physician; consent signed by family

Exclusion criteria:  unable to sit in chair for 30 minutes; apathetic; would require change in medication during intervention

Interventions

Experimental Group: intervention focused on strength training, balance, trunk movements and flexibility. Exercise routine supported with music

Type of physical activity: strength, balance

Frequency: daily, duration = 30 minutes

Time period: 3 months

Control Group: social contact 1-on-1 conversation with therapist

Frequency: daily, activity duration = 30 minutes

Time period: 3 months

Outcomes

Behaviour outcome: Beoordelingsschaal voor Oudere Patienten/Evaluation Scale for Elderly Patients

Cognitive Function outcomes:

1. MMSE

2. Amsterdam Dementia Screening Test 6

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Low riskCoin flipping
Allocation concealment (selection bias)Unclear riskNo description of methods used to conceal allocation
Blinding (performance bias and detection bias)
All outcomes
Unclear riskNot possible to blind participants and the personnel to the intervention allocated.
Blinding of outcome assessment (detection bias)
All outcomes
High risk"The physiotherapist who was conducting both treatments evaluated the patients on cognition. However, the nurses who scored the patients on behaviour were all blind to the group assignment"
Incomplete outcome data (attrition bias)
All outcomes
Low risk1 participant in control group unable to complete 3-month MMSE and ADS 6 due to hip fracture
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskAttendance and adherence not stated

Venturelli 2011

Methods6-month, randomly assigned experimental trial
Participants

Country: Italy

Centre: nursing home, specifically Alzheimer care unit

Diagnosis: moderate to severe AD

Participants: 24 at baseline, 21 completed

Baseline: 24 (all women)

Experimental Group: n = 12; mean age (SD) = 83 years (6)

Control Group: n = 12; mean age (SD) = 85 years (5)

Inclusion criteria: 65 years or older; dependent on assistance in 2 or more personal ADLs according to the Barthel index; Mini-Mental State Examination (MMSE) maximum score of 15 and minimum of 5; absence of mobility limitations, minimum score of 23, according to the Performance Oriented Mobility Assessment (POMA) index; and constant oxygen saturation during walking (SpO2 > 85%).  According to the clinical dementia rating scale, all nursing home residents had to be in the later stages (CDR3-CDR4) of AD

Exclusion criteria:  none stated

Interventions

Experimental Group: a minimum of 30 minutes of moderate walking 4 times a week for 6 months

Type of physical activity: aerobic

Control group: usual care at the home, which consisted of bingo, sewing, music therapy

Outcomes

Cognitive function outcomes: MMSE

Activities of daily living outcome: Barthel Index for ADLs

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear riskMethod of random selection not described
Allocation concealment (selection bias)Low risk"The head nurse of the ACU (not involved in the residents assessments) did the participants’ randomization using StatsPlus for Macintosh"
Blinding (performance bias and detection bias)
All outcomes
Low risk" . . . members of the research team did not know to which group each participant had been assigned . . . No one on the research team was present during the walking exercise"
Blinding of outcome assessment (detection bias)
All outcomes
Unclear risk"Evaluation was done before and after the experiment period in a blind way" - not described well
Incomplete outcome data (attrition bias)
All outcomes
Low risk

Attrition: Experimental Group = 1 (8.4%); Control Group = 2 (16.7%)

Reasons for attrition stated for each group

Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Vreugdenhil 2012

Methods4-month RCT
Participants

Country: Australia

Location: home

Diagnosis: mild to moderate AD

Participants: 40 at baseline (24 women and 16 men), all of whom completed; mean age = 74.1 years

Experimental Group: n = 20; mean age 73.5 years; mean education = 10.1 years; mean MMSE (SD) = 22.9 (5.0)

Control Group: n = 20; mean age 74.7 years; mean education = 10.3 years;  mean MMSE (SD) = 21.0 (6.3)

Inclusion criteria:  diagnosed with dementia using DSM IV criteria; diagnosed with AD with NINCDS-ARDRA criteria; from outpatient memory disorder clinic; community dwelling with live-in care provider or caregiver that could visit daily

Exclusion criteria: physical condition that could prevent participation; evidence of neurodegenerative disorder (other than AD); already in exercise program more than once a week (resistance or aerobic training); started dementia medications in last three months

Interventions

Experimental Group: exercises progressively became more challenging, and targeted strength and balance. Also included brisk walking

Type of physical activity: aerobic, strength, balance

Frequency: daily, with 10 simple exercises and 30 minutes of brisk walking

Time period: 4 months

Control Group: usual care

Outcomes

Cognition outcomes:

1.      Alzheimer's Disease Assessment Scale

2.      MMSE

ADL outcome: Barthel Index of ADLs

Depression outcome: Geriatric Depression Scale

Caregiver burden outcome: Zarit Burden Interview

Notes 
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Low riskUsed computer-generated random allocation sequence
Allocation concealment (selection bias)Low riskSequentially-numbered, sealed opaque envelopes
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low riskOutcomes assessors blinded
Incomplete outcome data (attrition bias)
All outcomes
Low risk100% of participants completed the trial
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Williams 2008

  1. a

    Abbreviations

    > = greater/more than
    < = less than
    ≥ = greater than or equal to
    ACU =
    AD = Alzheimer's disease
    ADL = activities of daily living
    CDR3 =
    CDR4 =
    CSDD = Cornell Scale for Depression in Dementia
    CVA =
    DSM IV = Diagnostic and Statistical Manual of Mental Disorders classification system
    h = hour(s)
    ICD-10 =
    ITT = intention-to-treat (analysis)
    m = metres
    MMSE = Mini Mental State Examination
    MMSE-KC =
    NINCDS-ARDRA = National Institute of Neurological and Communicative Diseases and Stroke-Alzheimer Disease and Related Disorders Association
    RCT = randomized controlled trial

Methods16-week, quasi-experimental design, randomly assigned trial
Participants

Country: USA

Multicentre: 8 long-term care facilities

Diagnosis: moderate to severe AD

Participants: 45 at baseline, all of whom completed (89% female); mean age= 87.9 years (5.95); mean MMSE (SD) = 7.3 (6.19)

Experimental Group 1: n = 16

Experimental Group 2: n = 17

Control Group 3:  n = 12

Inclusion criteria: live in long-term care facility; evidence of AD as per NINCDS-ARDRA  criteria;  able to walk with assistance; CSDD score ≥ 7; dependent in at least 1 of the following: transfers, balance or gait, bed mobility

Exclusion criteria: ability to walk unaided for 30 minutes or more

Interventions

Experimental Group 1: exercise focusing on strength, flexibility, and balance. In addition participants walked each session.

Type of physical activity: aerobic, strength, balance

Frequency: 5 days per week, exercise duration gradually increased to 30 minutes (20 minutes of exercise session was spent walking)

Time period: 16 weeks

Experimental Group 2: supervised walking

Frequency: 5 days per week, exercise duration gradually increased to 30 minutes

Time period: 16 weeks

Control Group 3: social contact-conversation

Frequency: 5 days per week, activity duration equivalent to experimental groups

Time period: 16 weeks

OutcomesDepression outcome: Cornell Scale for Depression in Dementia
NotesThose who could walk 30 minutes or more without assistance were excluded from the trial
Risk of bias
BiasAuthors' judgementSupport for judgement
Random sequence generation (selection bias)Unclear risk"Participants were assigned a code number, which was drawn by a research assistant who had no access to pre-test results"
Allocation concealment (selection bias)Unclear riskMethods used to conceal allocation not described
Blinding (performance bias and detection bias)
All outcomes
High riskNot possible to blind participants and the personnel to the intervention allocated
Blinding of outcome assessment (detection bias)
All outcomes
Low risk"Raters were blinded to treatment group allocation"
Incomplete outcome data (attrition bias)
All outcomes
Low riskAttrition rate 20%, details provided, differences in drop-outs between groups were not significant. ITT analysis
Selective reporting (reporting bias)Low riskAll outcomes reported
Other biasLow riskNone apparent

Characteristics of excluded studies [ordered by study ID]

StudyReason for exclusion
Aman 2009No randomization
Anon 1986Participants not diagnosed with dementia (residents of senior citizens' housing)
Arcoverde 2008No randomization
Batman 1999Unknown study design (may not be RCT), unknown age of participants, not able to contact author
Burgener 2008Treatment included more than exercise (i.e. cognitive behavioural therapy and support group)
Christofoletti 2011Not a true randomization
Heyn 2008Compared cognitively-impaired with normal older adults
Kerse 2008Participants were not diagnosed with dementia
Kwak 2008Participants do not appear to have been randomly assigned to groups
Littbrand 2006Participants not diagnosed with dementia (older, dependent people)
Littbrand 2011Did not assess any of the primary or secondary outcomes of this review
Netz 1994Participants not diagnosed with dementia (cognitive deterioration and/or depression)
Netz 2007Did not assess any of the primary or secondary outcomes of this review
Obisesan 2011Control group was stretch exercise
Onor 2007Treatment was not physical activity
Oswald 2007Treatment was combined cognitive and physical activity
Powell 1974Participants not diagnosed with dementia (geriatric mental patients)
Rodgers 2002Participants not diagnosed with dementia (elderly veterans)
Scherder 2005Participants not diagnosed with dementia (mild cognitive impairment)
Tappen 2000Outcome measured was mobility and not ADLs
van Uffelen 2005Participants not diagnosed with dementia (mild cognitive impairment)
Viscogliosi 2000Participants not diagnosed with dementia (mild cognitive impairment)
Williams 2007This article examined mood and affect and not depression
Yagüez 2011Intervention was non-aerobic "Brain Gym". Outcome measures were sustained attention, visual memory, and working memory

Characteristics of studies awaiting assessment [ordered by study ID]

Hasselbalch 2012

Methods 
Participants 
Interventions 
Outcomes 
Notes 

NCT01935024

MethodsBenefits of Exercise in Alzheimer's Disease, Date Accessed 6 Nov 2013
Participants 
Interventions 
Outcomes 
Notes 

Volkers 2011

Methods 
Participants 
Interventions 
Outcomes 
Notes 

Characteristics of ongoing studies [ordered by study ID]

Cerga-Pashoja 2010

Trial name or title

Evaluation of exercise on individuals with dementia and their carers: a randomized controlled trial

Trials 11, 53. 2010. PUBMED 20465799

MethodsRandomized, single-blind controlled trial
ParticipantsAiming to recruit 146 people with dementia and their carers
InterventionsParticipants will be randomized into 2 groups: 1 trained in a structured, tailored walking program, while the other continues with usual treatment
OutcomesNot known
Starting dateNot known
Contact information

acerga-pashoja@nhs.net

CNWL NHS Foundation Trust

Stephenson House

75 Hampstead Road

London England NW1 2PL

Tel: 020 3214 5886

NotesCurrently at recruitment stage

Cyarto 2010

Trial name or title

The fitness for the Ageing Brain Study II (FABS II): protocol for a randomized controlled clinical trial evaluating the effect of physical activity on cognitive function in patients with Alzheimer's disease 

Trials 11, 120. 2010. PUBMED 21143943

MethodsParticipants will be randomly allocated to 2 treatment groups: usual care group or 24-week home-based program
ParticipantsThe study will recruit 230 community-dwelling participants diagnosed with Alzheimer's disease
InterventionsA 24-week home-based program consisting of 150 minutes per week of tailored moderate physical activity
OutcomesNot known
Starting dateNot known
Contact informatione.cyarto@nari.unimelb.edu.au
NotesCurrently at recruitment stage

Gennep van 2011

Trial name or title

Effects of a program combining walking and cognitive training on memory and behaviour of older persons with dementia

http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3121

MethodsMulticentre, randomized, controlled single-blind study
ParticipantsTarget number of participants is 164
InterventionsParticipants will be randomized to 1 of 4 interventions:
1. Combined intervention: walking and cognitive training (face-name learning)
2. Cognitive training (face-name learning)
3. Walking
4. Social visits
OutcomesNot known
Starting dateNot known
Contact informationGennep van, Martin, Netherlands
NotesCurrently enrolling participants, expect to complete in 2014

Laks 2012

Trial name or title

Physical exercise as an additional treatment for Alzheimer disease http://clinicaltrials.gov/ct2/show/NCT01515982

Date accessed 6 Nov 2013

MethodsRandomized controlled trial, double-blinded, with 16-week follow-up
ParticipantsEstimated enrolment is 60 elderly people with Alzheimer disease
InterventionsParticipants will be randomly assigned to an exercise group (on a treadmill) and a control group
OutcomesNot known
Starting dateNot known
Contact information

jlaks@centroin.com.br

Federal University of Rio de Janeiro

NotesTrial ongoing until December 2013

Lamb 2011

Trial name or title

Physical activity programs for community dwelling people with mild to moderate dementia (DAPA – Dementia And Physical Activity): a multi-centre, randomized controlled trial

http://www.controlled-trials.com/ISRCTN32612072/

MethodsParticipants will be randomly allocated to 2 treatment groups: usual care group, or 4-month exercise program with follow-up at 6 and 12 months
ParticipantsParticipants must meet the following criteria:
1. Have probable dementia of mild to moderate severity
2. Be able to participate in a structured exercise program:
a) able to walk 10 feet without human assistance
b) have no serious unstable illness (e.g. unstable angina)
3. Live in the community, either alone or with a relative, friend or carer, or in sheltered accommodation
InterventionsThe trial has 2 groups; 1 group (half the participants) will continue with their current treatment, while the other group (half the participants) will take part in the DAPA exercise program as well as their current treatment. The exercise intervention will be delivered in a group format, with up to 14 participants in each group. The program will be provided in 2, 1-hour sessions per week for 4 months, supplemented with between-session at-home exercises of at least 1 hour per week.
OutcomesNot known
Starting dateNovember 2011
Contact information

S.Lamb@warwick.ac.uk

Warwick Clinical Trials Unit at the University of Warwick

NotesTrial ongoing until May 2016

Logsdon 2012

Trial name or title

Two interventions for early stage dementia: a comparative efficacy trial

http://clinicaltrials.gov/ct2/show/NCT01550718 Date accessed 6 Nov 2013

MethodsRandomized, single blind
ParticipantsEstimated enrolment is 240
Interventions3 groups: 2 intervention groups (physical activity, and social activity), and 1 usual care control group
OutcomesNot known
Starting dateNot known
Contact information

logsdon@u.washington.edu

University of Washington

NotesTrial ongoing until Dec 2013

Pitkala 2010

Trial name or title 
MethodsRandomized
Participants210 patients randomized into 3 groups (70 per arm)
Interventions

Participants randomized into three arms:

1) tailored home-based exercise twice weekly;

2) group-based exercise twice weekly in rehabilitation centre;

3) control group with usual care and information about exercise and nutrition

OutcomesNot known
Starting date 
Contact information 
NotesAnalysing results

Potemkowski 2011

Trial name or title

Influence of physical activity on cognitive dysfunction in patients with mild and moderate Alzheimer dementia Neurodegenerative Diseases

Conference: 10th International Conference AD/PD - Alzheimer's and Parkinson's Diseases: Advances, Concepts and New Challenges Barcelona Spain. Conference Start: 20110309 Conference End: 20110313

Conference Publication 8. 2011

MethodsNot known
Participants240 participants recruited
Interventions4 groups: study group with mild dementia, study group with moderate dementia, control group with mild dementia, control group with moderate dementia
OutcomesNot known
Starting dateNot known
Contact informationandrzej.potemkowski@wp.pl
NotesStudy ongoing

Rosendahl 2012

Trial name or title

A high-intensity functional exercise program for older people with dementia and living in residential care facilities (The Umeå Dementia and Exercise Study)

ISRCTN: http://isrctn.org/ISRCTN31767087 Date accessed 6 Nov 2013

MethodsCluster-randomized controlled trial
ParticipantsOlder people with dementia living in residential care facilities; target number of participants = 183
InterventionsTwo groups: exercise, and control (activities while sitting)
OutcomesNot known
Starting dateNot known
Contact informationerik.rosendahl@physiother.umu.se
NotesStill collecting data

Ancillary