Health, mortality, and wellness issues in adults with cerebral palsy
CONFLICTS OF INTEREST
The author declares no conflicts of interest.
Margaret A Turk at Department of Physical Medicine and Rehabilitation and Pediatrics, SUNY Upstate Medical University, Syracuse, NY, USA. E-mail: email@example.com
For many years, children with cerebral palsy (CP) and their parents have been told that health and functional status stabilize by early adulthood. However, adults with CP report ongoing health conditions and aging and secondary conditions that are not always recognized or managed by their healthcare providers. There is a growing body of literature to better define the health, mortality, and wellness of those aging with CP. In general, adults with CP report good health, although health outcomes appear to be linked to the severity of CP and to increasing age. Studies reporting on lifespan warrant caution in interpretation because of biases in the survey and surveillance systems. It appears that lifespan of persons with CP is at or close to that of the typical population. The most commonly reported age-related changes and secondary conditions involve pain/fatigue, physical performance, and the musculoskeletal system. Not all adults have serious health problems, and many now recognize the aging process as a natural course of events. Few adults with CP engage in typical screening and health promotion activities due to a variety of barriers. There continues to be much to be learned and disseminated, in order to improve the care of adults with CP.
The issues of aging and secondary conditions in persons with mobility disabilities have become of considerable interest to researchers and clinicians in recent years. However, persons with disabilities have been concerned about these issues throughout their lifetimes, and they have been questioning healthcare professionals about the expectations for lifelong function. For years, children with cerebral palsy (CP) and their families have been told that health and functional status, mobility, and musculoskeletal problems would essentially stabilize by early adulthood. However, as more people with such disabilities live through their adult years, it is apparent that mobility, functional status, and musculoskeletal changes commonly continue into adulthood, and health concerns persist. Much of the conventional wisdom about aging and secondary conditions for adults has been communicated through the network of persons with disabilities.
There are no national surveillance programs in the USA that monitor CP (or most other childhood-onset disabilities) by severity, medical conditions and health, or the trajectory of aging. In general, national surveillance tools focus on functional limitations and participation, rather than on specific diagnoses or primary conditions and do not include International Classification of Diseases (ICD-9 or ICD-10) codes. The only estimate of adults with early-onset disabilities is by Verbrugge and Yang1 and based on data from the 1994 National Health Interview Survey Disability Supplement, Phase 1. This estimate suggests that 7 to 9% of adults reporting a disability had onset of a disability before the age of 20 years. Diagnoses typical of rehabilitation, developmental pediatric, orthopedic, or neurology program settings are in a minority and therefore are usually not the primary focus of public health, surveillance, and policy programs. The information we do have does support an overall increasing population of adults with early-onset disabilities.
There is a growing body of literature about aging issues and secondary conditions among adults with CP. Most information has been published in the last 10 to 15 years. These reports are often based on studies that have used convenience samples or only a few participants. They have used a cross-sectional design, with conclusions drawn from patient reports, clinical observations, recorded ICD-9 codes for additional health conditions, and recorded (not verified) causes of death. Some international studies based on registries offer some insights into health outcomes within a population of limited diversity and differing healthcare systems. There are no US longitudinal studies that would help us better understand lifelong issues, the impact of early interventions later in life, or risk for persistent or new adverse health outcomes in individuals with CP. Results of multiple studies are often difficult to compare because of a lack of common outcome measurement tools and inaccurate use of terminology or instruments (e.g. standardization of tools for disabilities, severity markers, secondary conditions, International Classification of Function [ICF] language). Most studies identify health issues or concerns, but few discuss prevention or intervention strategies.
Mortality among people with CP appears to be related to the severity of impairments. This is very clear in the pediatric population,2–6 where severity of intellectual disability and motor function, presence of epilepsy and feeding problems, and low birthweight have all been implicated. For adults, this information is less clear for at least three reasons: (1) there may be a cohort bias when comparing mortality data from those born before the 1980s with data from a younger adult population; (2) survival into adulthood may imply a healthy-survivor effect; and (3) with increasing age, the general population also has an increasing mortality.
A large database in California, defined by financial and service support needed and especially representative of the more severely impaired individuals with CP, provides significant information about adults with CP in the USA. However, one should be cautious in making generalizations on the basis of the information in this database, considering its inherent bias. Studies based on this database have reported the following results: survival of higher-functioning adults is close to that of the general population;7 older participants who had lost the ability to walk by age 60 years had poorer survival and those with the most severe disabilities rarely survived to age 60;8 and there is improved survival for adults with gastrostomy tubes in particular over a 20-year period,9 indicating improvements in treatment and care of the most fragile individuals with high levels of impairment. Another study with this database reported standardized mortality ratios being higher for mortality in general, and even higher ratios in the most severe group, with a decrease in this discrepancy with age.10 There is a reported increase in neoplasms as a cause for death; for example death rates for breast cancer were three times as high in the CP population as in the population at large. This discrepancy may be due to severity of impairment but it is more likely related to poor screening. The highest overall mortality ratio was for intestinal obstruction; the number of deaths due to respiratory etiologies was lower than is generally thought.
Reports from abroad also indicate that life expectancies for adults with mild-to-moderate CP are close to those of the general population. Hemming et al.4 reported on adults with CP in a 1940 to 1950 birth cohort in the UK. Assuming survival to age 20 years, almost 85% of people with CP, compared to 96% of the general population, survived to age 50. Compared with deaths in the general population, more of the deaths in adults with CP in their 20s and 30s were due to respiratory causes; relatively more deaths in adults with CP in their 40s and 50s were due to circulatory conditions and neoplasms. Few deaths in adulthood were attributed to CP, although the nervous system was implicated more in these adults with CP than in the general population. The Western Australia Cerebral Palsy Registry noted that the strongest single predictor of mortality was intellectual disability.11 This study further noted that higher motor impairment severity increased the risk of early mortality, not mortality in adulthood, with mortality declining after age 15 years and remaining steady for the next 20 years.
All these studies must be judged in the context of cohort effects noted above, and details may not be generalizable to the young-adult population with CP.
The health status of individuals with disabilities is poorly understood. However, the general health of adults with CP is self-reported as good or satisfactory to excellent,12,13 a finding comparable to that of the community at large.13 Self-perceived health ratings and life satisfaction may be related to the presence of pain or to functional changes over time, but not to the severity of impairment.14–16
No serious health problems were reported by 101 adults with CP recruited through a California affiliate of United Cerebral Palsy Association.12 In this sample, the majority of whom had CP of moderate severity, 76% overall reported musculoskeletal problems (e.g. contractures, deformities, pain); 63% of those under 50 years of age reported such problems. Urinary incontinence occurred in about half of persons who did not walk. The lack of preventive healthcare was remarkable.
In a cross-sectional study of 215 adults with CP in upstate New York, persons with CP were overwhelmingly healthy (based on clinical information and self-report) and reported no significant health problems, but they were nonetheless worried and concerned about their health status and futures.13,17 Most commonly reported health conditions were pain and musculoskeletal, bladder and bowel, and dental problems. Most adults with CP did not admit to tobacco use or drug abuse, had very limited sexual activity but also low use of protection, and did not engage in exercise. Preventive health participation was limited for females with mobility problems living in the community, although more common for those in state-supervised congregate living residences.13
A study of adults with a variety of developmental disabilities having intellectual disability in common, living in group homes (possibly indicating a more-impaired population), noted that the health conditions increasing with age among adults with CP were those that could be expected – cardiovascular, respiratory, and hearing/vision problems.18 These findings have been essentially replicated in Taiwan and Israel.19,20 Only gastrointestinal disorders were found to be more common in the subset of adults with CP and intellectual disability. Of interest is that in comparison to US norms, the full cohort of adults with intellectual disability had less cardiovascular risk factors than did the general population; either this is a healthier population or screening and monitoring have not been effective in this population with disabilities. In looking more critically at the subset of adults with CP with intellectual disability, the severity of the functional impairment of CP, more than the diagnosis of CP alone, predicted increasing health problems with age.21 Vision and hearing problems may have been present early, and as anticipated there was an increase in vision and hearing problems with age.22 Obesity/overweight is reported in adults with intellectual disability, where CP is a subset, not usually in samples of adults with CP only.
Despite self-reports of good health, a Canadian publication notes that the rate of outpatient visits among young adults with CP is 1.9 times higher than that of age-matched peers.23 However, adult females with CP in upstate New York reported 3.0 doctor visits per year compared to 3.1 visits for females in a national health survey.13
Pain and Fatigue
Pain is the most consistent health condition reported by adults with CP.12,13,17,24,25 It has been reported in a number of samples of adults with CP, at a variety of ages, to be 30 to 80%, with activity limitation reported to be moderate to severe. Most studies do not report the etiology. Pain may be present for a variety of reasons, and may be acute, recurrent, or chronic.
Most pain complaints are identified as originating in the joint closest to the pain, although specific questioning often reveals that other structures are involved. Most people report ‘arthritis’ as the etiology; however, these pains may originate from either joints or muscles. A good history and clinical examination can help identify the source of pain and direct the clinician to prescribe appropriate treatment. Pain can cause, or be caused by, increased spasticity, weakness, falls, or progression of contractures or deformities. Pain reports may be difficult to elicit because of communication difficulties or severe intellectual disability. Because of the high prevalence of pain in this population, the healthcare provider should ask adults with CP about pain and implement necessary intervention. Pain may cause changes in function, living arrangement, or social interactions.
Back, leg, and hip pain complaints are common in persons with CP,15,26 and cervical pain is also common.12 The incidence of reported pain is greater in individuals with spasticity and those with higher function.13,26 Women often have more complaints than men.13,15,26 Chronic pain (present for >3mo) is common, and reports of pain can be daily and characterized as moderate to severe intensity.15,27 Pain is poorly recognized and treated in this population, and most pain treatments are moderately helpful.28 However, adults with CP tend to self-manage their pain,29 and for those who seek medical care, few options are offered.28 The pain does not appear to increase dramatically over time.30 Treatment of chronic pain using traditional cognitive-behavioral approaches to decrease catastrophizing and using pacing for task persistence may be helpful.31
Fatigue often incites pain, and exercise most commonly relieves pain in adults with CP. 27 Fatigue is also associated with pain in adults with CP,32 and along with deterioration of skills and low-life satisfaction, is unrelated to type or severity of CP. Increase in task persistence and decrease in resting (i.e. fatigue) and catastrophizing were associated with decreases in reports of depression, and task persistence was associated with decreases in pain interference,31 Sleep disruption is commonly seen with pain and fatigue. Anecdotally, the pain/fatigue complex appears to respond positively to directed pain management, focused therapies, behavioral treatments, good sleep hygiene, medications, and exercise.
As is seen in the general population, there is at least a modest decrease in the functional status of adults with CP with aging. About a third of participants report modest-to-significant decreases in walking or self-care tasks,8,13,33–35 especially in dressing and walking. A relative sparing of other self-care or social activities was reported in two of these studies.8,13 Analysis of the large California database regarding functional changes noted that after age 25, adults would likely not see improvement in walking and that function would remain relatively stable over the next 15 years.36 The possibility of functional decline, could not, however, be ruled out. The reason for even modest decreases in skill is not clear and may be related to lack of environmental modifications, lack of access to or participation in exercise or activity programs, pain, aging (e.g. decreased endurance, flexibility, strength, or balance), other medical conditions, or progressive neurological problems (e.g. cervical spine stenosis, radiculopathy). Therefore, functional decline between the ages of 25 and 40 years, or more significant decline at any time in adulthood, warrants further assessment and treatment.
Changes in functional status often result in a need to alter living arrangements, which can be traumatic. Increased need for assistance in mobility and self-care with aging is a common complaint of adults with mobility impairments. Falls often presage the acknowledgment of decreasing abilities. Significant changes in mobility or falls should not be accepted as an inevitable part of a congenital or childhood-onset disabling condition in the adult years. Treatable etiologies for these changes should be sought.
Cross-sectional and convenience samples suggest that adults with CP may show musculoskeletal or performance changes typical of advanced aging earlier than their non-disabled peers.12,15,37 These changes are as yet unproven and require confirmation through longitudinal controlled studies. If verified, these earlier-than-expected aging changes would be considered secondary conditions.
Wellness and Health Promotion
Self-reports, as well as published studies, indicate that adults with CP enjoy generally good health. This may come as a surprise to health professionals, who often equate health and wellness to lack of disability and/or fewer health conditions. Although the health construct of adults with disabilities is poorly understood, it is known to be different from that of the general population.38 People with disabilities tend to have lower expectations for and general indicators of wellness. A qualitative report of adults with CP noted planning, battling, or concealing are strategies used to combat feelings of restriction and limited autonomy.16 For this reason, typical instruments of health perception and quality of life may not capture the sense of health for adults with CP. They may, however, give some suggestions for ways to support wellness and engagement in healthy activities.
Adults with CP reportedly participate to only a limited extent in health screening and wellness activities.12,13,17 People with mobility impairments may receive immunizations as a part of preventive health services, but are less likely to receive other preventive services such as routine Pap smear and mammography screening.39 Capriotti40 reported that women with disabilities had less knowledge about cardiovascular risks and no screening for risk factors, despite their higher risk because of their low-activity levels. On a more positive note, minor modifications in office screening techniques for adults with intellectual disabilities can improve identification of risk factors and health needs, with improved health determinants.41
Exercise is a health-promotion activity that is poorly utilized by adults with CP, although it would seem natural to engage in that activity to improve performance. Both attitudinal and environmental barriers usually limit this activity. Exercise is a well-known health-promoting behavior, and its positive effects have been demonstrated in persons with disabilities.42–46 These activities can be managed through home programs and health clubs, not just traditional physical therapy programs. The old adage that exercise consists of continuing one’s typical activities, even if considered ‘strenuous’ (e.g. propelling a wheelchair, walking in the home), is incorrect. Performing these activities without increasing distance, time engaged, or resistance used will not increase strength, conditioning, or performance. Personal choices for participation in exercise and activities by people with disabilities, or specifically with CP, have not been well explored, but likely relate to the readiness to change and self-efficacy that is an important part of health-promotion participation in individuals without disabilities.
Published mortality and health information indicates that functional status shows a modest decrease with age, but significant changes should not be expected. Although these studies have their biases, and one must be cautious in generalizing this to a younger population, the data are compelling. Severity of impairment and increasing age are linked to mortality, number of health conditions, and functional changes with time; however, given the absence of longitudinal information it is unclear whether the severity and age relationship is continuous. Chronic and associated conditions noted early in life (e.g. constipation, vision impairment) persist into adulthood, and there are no comorbidities (e.g. hypertension, diabetes) known to be associated with CP and aging. Secondary conditions, specifically the pain/fatigue complex, may be the early aging effects often reported. Health screening and health promotion activities are limited for adults with CP, and attitudinal and environmental barriers likely limit participation. Self-rated health constructs for adults with CP are poorly understood and may also factor into reports of satisfaction and personal choice for participation in health-promotion activities.
The state of the science regarding the health of adults with CP has improved over recent years, although less information is still available about adults than about children. Most studies continue to report on a limited number of participants, although there have been reports from larger databases and surveillance programs, both within the USA and internationally. The information from these reports must be used with caution, given the biases cited earlier. The research studies often do not use common indicators, outcome measures, or language about disability; consequently, interpretation, comparisons, and generalization are often uncertain. Nonetheless, the information does provide a good foundation for continued research and clinical practice (although with some caution and reservations).
Gaps in the science are numerous. Among the most prominent are the limited availability of information on evidence-based practices; a lack of knowledge of the natural history of those with CP over a lifetime; and inadequate understanding of disparities in health and healthcare related to survey instruments, surveillance programs, regional practice, disability severity, epoch, and comparisons to non-disabled populations. The relationship between the level of disability or type of CP and health outcomes, performance change, and pain is not well understood. We also need additional information about chronic pain management (traditional, new, and alternative techniques), the impact of common interventions acutely and over a lifetime, age-related changes, and the influence of disease severity, cognitive impairment, and resiliency on health and function. The mental health issues associated with, or resulting from, disability are not well understood. We lack cost information about performance changes over time and their relationship to and influence over living arrangements, employment/retirement, support needs, healthcare, and insurance support. We do not have sufficient information about the effectiveness of screening and health-promotion activities, especially exercise, over a lifetime. Health care providers and consumers have limited knowledge on which to base decisions regarding adult health issues and anticipated changes in function in adults with disabilities.
Despite the increase in research and published information, much remains to be learned and shared about how to improve the care of adults with CP.