SEARCH

SEARCH BY CITATION

Keywords:

  • Addictive behaviours;
  • population prevalence;
  • public health

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

Background and aims

Addictive behaviours are among the greatest scourges on humankind. It is important to estimate the extent of the problem globally and in different geographical regions. Such estimates are available, but there is a need to collate and evaluate these to arrive at the best available synthetic figures. Addiction has commissioned this paper as the first of a series attempting to do this.

Methods

Online sources of global, regional and national information on prevalence and major harms relating to alcohol use, tobacco use, unsanctioned psychoactive drug use and gambling were identified through expert review and assessed. The primary data sources located were the websites of the World Health Organization (WHO), the United Nations Office on Drugs and Crime (UNODC) and the Alberta Gambling Research Institute. Summary statistics were compared with recent publications on the global epidemiology of addictive behaviours.

Results

An estimated 4.9% of the world's adult population (240 million people) suffer from alcohol use disorder (7.8% of men and 1.5% of women), with alcohol causing an estimated 257 disability-adjusted life years lost per 100 000 population. An estimated 22.5% of adults in the world (1 billion people) smoke tobacco products (32.0% of men and 7.0% of women). It is estimated that 11% of deaths in males and 6% of deaths in females each year are due to tobacco. Of ‘unsanctioned psychoactive drugs’, cannabis is the most prevalent at 3.5% globally, with each of the others at < 1%; 0.3% of the world's adult population (15 million people) inject drugs. Use of unsanctioned psychoactive drugs accounts for an estimated 83 disability-adjusted life years lost per 100 000 population. Global estimates of problem gambling are not possible, but in countries where it has been assessed the prevalence is estimated at 1.5%.

Conclusions

Tobacco and alcohol use are by far the most prevalent addictive behaviours and cause the large majority of the harm. However, the quality of data on prevalence and addiction-related harms is mostly low, and comparisons between countries and regions must be viewed with caution. There is an urgent need to review the quality of data on which global estimates are made and coordinate efforts to arrive at a more consistent approach.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

Addictive behaviours (primarily alcohol consumption, tobacco smoking and unsanctioned psychoactive drug use1) are major contributors to the global burden of morbidity and premature death [1]. Problem gambling also incurs significant societal and individual costs [2]. Addictive behaviours impose a high economic burden on society through health-care costs, public safety, crime and lost productivity, as well as other social costs [3]. It is important to be able to have readily available, up-to-date prevalence and other estimates relating to these behaviours at global, regional and national levels to track progress towards reducing this burden, to help set policy priorities and to help evaluate policies.

Information of this kind is available, but two main factors limit its usefulness. First, alcohol, tobacco, other drug use and gambling are usually addressed separately, making it problematic to gain an overview of addictive behaviours as a whole. Secondly, data are of variable quality, and it is not clear which figures are most accurate and comparable across countries.

Addiction has commissioned this paper as the first in what is intended to be a series on global statistics on addictive behaviours. This paper is both a commentary on online sources of information on the prevalence and harms of addictive behaviours and an overview of the current status of addictive behaviours globally. It is intended that future papers will update and expand the scope of the statistics that are collated, and the analyses undertaken.

Aims

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

The aims of this report were (1) to identify major online, publicly accessible sources of data on addictive behaviours; (2) to use these to provide the best available estimates of global and regional prevalence of addictive behaviours (alcohol consumption, tobacco smoking, unsanctioned use of psychoactive drugs and gambling) and related harms; and (3) to provide an expert review of the quality of the data available.

Methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

Online sources of information were identified through expert review and web searches. Major sources of global and regional information were assessed, along with national-level information for countries known to have systems for monitoring addictive behaviours. The strengths and limitations of the online sources identified were assessed and compiled as a commentary on available online information. The websites of the World Health Organization (WHO) and United Nations Office on Drugs and Crime (UNODC) provide the most comprehensive data on addictive behaviours globally, both as downloadable data sets and through regular publications. The data compiled in this report were obtained primarily from these sites. The Joint United Nations Programme on HIV/AIDS (UNAIDS) and the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) provided other sources of information (the latter primarily for the European region).

Available country-level estimates of the prevalence of, and major harms associated with, alcohol consumption and tobacco smoking were downloaded from the WHO website, and estimates of unsanctioned use of psychoactive drugs were downloaded from the UNODC website. The data selected related to the prevalence of use, and of harms related to the use of alcohol, tobacco and unsanctioned drug use as the outcomes of primary relevance to assessment of the public health implications of addictive behaviours. Information on regulatory responses to alcohol and tobacco are available, but this aspect was not considered.

Country-level data were imported into Microsoft Excel 2010, and codes to identify geographic region and economic status were added. Geographic regions were based on a listing from the United Nations Statistics Division (http://unstats.un.org/unsd/methods/m49/m49regin.htm#ftnb). Regions were then combined in order to provide an acceptable number of countries for which data were available in each regional group, while maintaining appropriate country associations. (Note: the WHO identifies geographic regions differently from the United Nations.) The list of least developed countries from the United Nations Statistics Division was the basis of the identification of economic status of countries as ‘least developed’ or ‘other’. The country-level data are available as supplementary files (see Supporting information).

Data were sorted by the codes indicating geographic or economic status grouping. For each indicator median, first and third quartile values were calculated. The nature of the data (much of the country-level data were age-standardized) and missing data prevented calculation of weighted means or confidence intervals. Median values, with first and third quartile values to provide an indication of the range, were selected as appropriate measures of central tendency without distortions from extreme values. Global estimates presented are median values, with first and third quartile values, for all countries with data.

Data on the prevalence of gambling were obtained from the website of the Alberta Gambling Research Institute (http://www.abgamblinginstitute.ualberta.ca/). As data on gambling are available from relatively few countries, these data are summarized in the text without further analysis.

Results

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

Online sources of information

Table 1 describes and comments on the online sources of information that were used.

Table 1. Description of, and comments on, major online sources of global and regional information on addictive behaviours.
AspectComment
1. World Health Organization (WHO) (www.who.int)
Addictive behaviours coveredCoverage is best for alcohol and tobacco, some information on burden of disease related to unsanctioned drug use, with links to information on HIV. Gambling is not monitored by WHO
Major reports
  • World Health Statistics: annual report with summary data on alcohol consumption and smoking as risk factors, and information on health systems
  • WHO Report on the Global Tobacco Epidemic: periodic report focusing on the status of tobacco control policies on a global basis
  • WHO Global Status Report on Alcohol and Health: published in 2011 and 2014; summarizes evidence on harms related to alcohol, global data on consumption and consequences, and policies and interventions
  • ATLAS on Substance Use: single report published in 2010; this report summarizes resources for the prevention and treatment of substance use disorders
  • Global Health Risks: single report published in 2009, based on 2004 data, provides information on 24 factors affecting health, with tobacco use, alcohol and illicit drugs considered as one risk category
  • WHO Global Report, Mortality Attributable to Tobacco: single report published in 2012, based on 2004 data used for Global Health Risks report
Downloadable dataGlobal Health Observatory Data Repository, apps.who.int/gho/data. Data on tobacco and alcohol. Tobacco control data reflect policies for prevention. Global Information System on Alcohol and Health—consumption, harms, patterns, economic aspects, control, prevention, youth. Data in table format; can be downloaded for manipulation or analysis. Available in seven languages. Data can also be retrieved by country
Strengths
  • A number of different maps, both static and interactive, are available, and can be reached through different links. The maps provide a quick visual overview of data and countries for which no data are available are clearly identified
  • The WHO website is large, but the data and statistics pages are reached through multiple links. There are also links to other sites, such as UNAIDS, which provide relevant information
Limitations
  • Gaps in data: WHO relies on reports completed by member states. There are large gaps in data, particularly for countries in Africa. The gaps limit the extent to which analyses can be carried out relating strategies and programs to prevalence of substance use
  • Age of data: WHO reports the latest available data, but it is often necessary to look at the detail to determine the age of the estimate, and gaps in data limit the extent to which analyses of trends can be undertaken
  • Finding explanatory notes: headings of maps and tables may not provide sufficient information to interpret the data reported, and the required information is not easily located. For example, graphs of the prevalence of alcohol use and substance use disorders do not provide the definition of ‘disorders’. Look for the Indicator Code Book as a particularly useful guide to the Global Information System on Alcohol and Health
2. United Nations Office on Drugs and Crime (UNODC) (http://www.unodc.org)
Addictive behaviours coveredUnsanctioned drug use only: the most comprehensive data are for opioid drugs, probably reflecting international treaties covering monitoring of drugs
Major reportWorld Drug Report: published annually, this is the most comprehensive compilation of data on unsanctioned drug use globally. Main aspects covered are production, trafficking and consumption and the consequences of illicit drug use in terms of treatment, drug-related diseases and drug-related deaths. Available in six languages
Downloadable dataUNODC Statistics (stats.unodc.org): look for the online tool for creating personalized reports. Available data includes, use, injecting, HIV and hepatitis, mortality, treatment demand, price, seizures. Tables are downloadable to pdf or Excel
StrengthsMaps and tables: these are included in the World Drug Report, but as they are large documents in themselves, it is useful to be able to download these as individual documents. Topics are prevalence in drug use, expert perceptions of trends and illicit drugs as a source of demand for treatment. The format of tables downloaded from the World Drug Report is better for manipulation than tables from stats.unodc.org
LimitationsGaps in data and age of data: UNODC, like WHO, are dependent on the information reported by member States. Data on illicit drug use in Southern Asia and Middle East countries are particularly limited, with data either not being reported or in some cases being 10 years old or more. UNODC defines geographic regions differently to WHO and some countries are listed differently complicating the combination of data
3. Joint United Nations Programme on HIV/AIDS (UNAIDS) (www.unaids.org)
Addictive behaviours coveredIncluded in our listing because of the significance of injecting drug use as a risk factor for transmission of HIV; however, data on HIV rates among injecting drug users globally are accessed more readily from the UNODC website, and prevalence of HIV among the general population is available from the WHO website
Major reportsAnnual reports on global AIDS epidemic, covering epidemiology, prevention and treatment of HIV/AIDS: coverage of injecting drug use is a minor component of the reports
Downloadable dataAIDSinfo: pre-set tables are downloadable to Excel
StrengthsCountry reports that can be generated via tool located under ‘Know your epidemic’. A spreadsheet tool is available for calculating the estimated number of new infections based on local prevalence
Limitations

● Gaps in data, capacity for analysis: as with all such information, coverage depends on what data are reported by member states. The site includes a number of tools for visualization of data, but there is little capacity for analysis

● Site navigation: navigation tools are not intuitive making the process of finding data on injecting drug use cumbersome

4. European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) (www.emcdda.europa.eu)
Addictive behaviours coveredUnsanctioned drug use only (alcohol, tobacco, gambling not covered), and only for countries in the European Union. The ‘Countries’ tab on the home page is a quick link to the list of countries included, as well as links to available topics
Major reportsAnnual report on the state of the drugs problem in Europe: main report for data on patterns of drug use in Europe
Downloadable dataStatistical Bulletin by year and country (emcdda.europa.eu/stats13): there is a facility to produce tables that can be downloaded and combined for analysis. A link to a help page gives comprehensive information and explanatory notes. Data topics include prevalence and population estimates, infectious diseases and deaths, treatment demand and health and social responses and crime, seizures and market data
Strengths

● Website design: good use of tabs, banners and linked lists to help users find information on the site. The publications database offers multiple indexing methods for locating publications of interest. The topics tab on the home page links to a good listing of topics, with separate listing of ‘Topics in the spotlight’. The summaries of these issues, such as ‘Synthetic cannabinoids in Europe’ are very good quality, often with interactive elements

● Maps and data sheets: interactive maps are well presented, with clear links to data sheets and country notes that provide information, and cautions on limitations in data

● Drug profiles: accessed from topics tab or quick links, the drug profiles provide good background information and pictures, covering a wide range of drugs that are used for non-medical purposes

Limitations

● Gaps and inconsistencies in data: like WHO and UNODC, EMCDDA can only report the data that are provided by member states

● Data on opioid drugs: population prevalence data cover cannabis, amphetamines, ecstasy and cocaine, not opioid drugs. Data on use of opioid drugs are included under ‘problem drug use’, which also covers injecting drug use

5. Alberta Gambling Research Institute (www.abgamblinginstitute.ualberta.ca)
Addictive behaviours coveredGambling only
Major reportsMain relevant resource is listing of international studies examining the prevalence of problem gambling. Listing includes 80 separate studies in 30 countries, mostly undertaken in the last decade
Downloadable dataData from international gambling prevalence studies available as spreadsheet or pdf (see http://www.abgamblinginstitute.ualberta.ca/LibraryResources/ReferenceSources/PrevalenceInternational.aspx)
StrengthsSummary of international gambling prevalence studies
LimitationsStudies of prevalence of gambling are available only for some developed countries
6. Global Tobacco Surveillance System (GTSS) (http://nccd.cdc.gov/GTSSData)
Addictive behaviours coveredTobacco use, based on four global surveys (youth tobacco, school personnel, health professions students, and adults
Major reportsData from GTSS contribute to multiple publications; the website contains links to published research related to the survey material
Downloadable dataData can be downloaded in various formats, based on the survey, region and country or location
StrengthsWebsite design: multiple options for using data online, with easy links to download options
LimitationsSurveys cover only tobacco use, with most data on tobacco smoking in the form of cigarettes, pipes and cigars
7. World Tobacco Atlas (www.TobaccoAtlas.org)
Addictive behaviours coveredTobacco use, drawing on data from the WHO and United States Centers for Disease Control and Prevention (CDC)
Major reportsThe Tobacco Atlas can be downloaded in pdf format, in multiple languages. Information from the Atlas is also available online as a series of topics
Downloadable dataNo data files can be downloaded. Relevant data are more readily obtained from the WHO and CDC websites
StrengthsSummary information in the topics pages on the website
LimitationsThe only addictive behaviour covered is tobacco use, and the data on the prevalence of tobacco use and related harms are several years old
8. Global Burden of Diseases (www.healthdata.org/gbd)
Addictive behaviours coveredAlcohol, tobacco, illicit drugs
Major reportsLinks to range of journal articles and other publications on global burden of disease
Downloadable dataWebsite has tool for selecting and downloading data
StrengthsInformation on wide range of different aspects of overall burden of disease that is useful for putting data on addictive behaviours into context for individual countries and regions
LimitationsThe same limitations on the availability of data, particularly on unsanctioned drug use, apply to the Global Burden of Diseases project

For some countries more up-to-date and accurate information is available, either from national statistical websites or publications. It was beyond the scope of this paper to investigate and document resources for all countries world-wide, but some sources for major English-speaking countries are summarized in Table 2. In addition, differences in methodology for these national surveys make cross-national comparisons problematic. The population survey data from individual countries are likely to be the basis of information reported to the WHO and UNODC and incorporated into their data sets, but this is difficult to determine.

Table 2. Listing of additional online sources of information for selected countries.
SourceType of information
United Kingdom
UK Health and Social Care Information Centre (http://www.hscic.gov.uk/home)Health and social care issues including alcohol consumption, reports on drug use among young people, data from surveys of secondary school pupils
Crime Survey for England and Wales (www.crimesurvey.co.uk)Reports from surveys of crime experienced by participants in the past year, including crimes that may not have been reported to police. Trafficking and possession of drugs are included, but the proportion of other crimes that may be drug-related is not reported
Public Health England (https://www.gov.uk/government/organisations/public-health-england)Reports and data on treatment
National Drug Treatment Monitoring System (http://www.nta.nhs.uk/uploads/annualdrugstatistics2012-13-statisticalreport.pdf or www.ndtms.net)Annual statistical reports on treatment
USA 
National Survey on Drug Use and Health (NSDUH) (http://www.samhsa.gov/data/NSDUH.aspx)National and state-level data on the use of tobacco, alcohol, unsanctioned drug use (including non-medical use of prescription drugs) and mental health among people aged 12 years and older in the United States. Survey data are available as reports, online analysis or downloadable data sets
Drug Abuse Warning Network (DAWN) (http://www.samhsa.gov/data/DAWN.aspx)Data from hospital emergency departments and drug-related deaths investigated by medical examiners and coroners
National survey of substance abuse treatment services (http://www.samhsa.gov/data/DASIS.aspx)Information on treatment facilities
TEDS, the treatment episode data set (http://www.samhsa.gov/data/DASIS.aspx?qr=t#TEDS)Information on treatment episodes
Monitoring the Future (http://www.monitoringthefuture.org/)A survey of 8th, 10th and 12th grade students which has been undertaken since 1975
Youth Risk Behavior Survey (http://www.cdc.gov/HealthyYouth/yrbs/)A national school-based survey in most US states, territories and some tribal schools, that includes questions on alcohol and drug use, tobacco use and HIV-related risk behaviours
Australia
National household surveys of alcohol and other drug use (http://www.aihw.gov.au/national-drugs-strategy-household-surveys/)Information on the surveys and links to reports, other sources of information on treatment, and a link to the Australian data archive
National survey of alcohol and tobacco use by secondary school students (http://www.srcentre.com.au/news-events/news/news-item/2012/12/10/australian-secondary-students-alcohol-and-drug-survey)Undertaken every 3 years. The link is for the most recent survey, undertaken in 2011
Illicit Drug Reporting System (IDRS) and Ecstasy and Related Drugs Reporting System (EDRS) (http://ndarc.med.unsw.edu.au)These projects use interviews with drug users and key informants to gain information on trends in unsanctioned drug use in Australia
Canada
Canadian Alcohol and Drug Use Survey (http://www.hc-sc.gc.ca/hc-ps/drugs-drogues/stat/index-eng.php)Links to data from all surveys—most recent survey undertaken in 2012
New Zealand
New Zealand Alcohol and Drug Use Survey (http://www.health.govt.nz/nz-health-statistics/national-collections-and-surveys/surveys/current-recent-surveys/alcohol-and-drug-use-survey)Links to reports and data from 2007/08 survey (the most recent undertaken)
New Zealand Tobacco Use Survey (http://www.health.govt.nz/nz-health-statistics/national-collections-and-surveys/surveys/current-recent-surveys/tobacco-use-survey)Links to reports and data—most recent survey undertaken in 2009

Summary data on prevalence of use and harms

The figures need to be considered as broad estimates because of variation in methodologies and recency of surveys. In addition, it is important to note that part of the between-country differences will be due to wide variation in the age distribution of their populations.

Alcohol

Summary data on the prevalence of alcohol consumption, potentially harmful levels of consumption and harms attributed to alcohol are shown in Table 3. These data are obtained from the WHO website (the Global Information System on Alcohol and Health), with details indicated in the footnotes to Table 3.

Table 3. Alcohol consumption, by geographic region, economic status and globally, and indicators of harm related to alcohol use.
Regiona [range of number of countries with data for each indicator]Prevalence of consumption, % in past 12 monthsbEstimated litres per capitacDrinkers with heavy episodic consumption, % in past 30 daysdPrevalence of alcohol use disorders, % in past 12 monthseDALYS due to alcohol use disordersf
MaleFemaleTotalMaleFemaleTotalMaleFemaleTotalMaleFemaleTotal
  1. Based on data from the WHO Global Information System on Alcohol and Health, with specific sources given below for each indicator. All data are median (first, third quartiles) values.

  2. a

    Countries allocated to geographic regions and group of least developed countries based on United Nations Statistics Division listing (http://unstats.un.org/unsd/methods/m49/m49regin.htm#ftnb). Numbers in square brackets indicate the number of countries in each grouping with data, showing the range for each indicator, or a single number if it was the same across all indicators.

  3. b

    Proportion of adults (15+ years) who have consumed any alcohol during the past 12 months, by gender. Source: WHO Global Health Observatory, available at: http://apps.who.int/gho/data/node.main.A1044?lang=en, accessed 28 November 2014. Country-level data are an average weighted by the respective populations.

  4. c

    Total (recorded 3-year average and unrecorded) adult (15+ years) per-capita consumption, litres of pure alcohol per person per year. Data are an average of 2008–10 estimates. Source: http://apps.who.int/gho/data/node.main.A1032?lang=en (accessed 28 November 2014).

  5. d

    Proportion of adult drinkers (15+ years) who have had at least 60 grams or more of pure alcohol on at least one occasion in the past 30 days, by gender. Source: http://apps.who.int/gho/data/node.main.A1047?lang=en (accessed 28 November 2014). Country-level data are an average weighted by the population of respondents who consumed any alcohol during the past 12 months.

  6. e

    Proportion of adults (15+ years) with alcohol use disorders during the past 12 months, by gender. Alcohol use disorders defined as harmful use of alcohol (ICD-10 F10.1) or alcohol dependence (ICD-10 F10.2). Country-level data are age-standardized. Source: http://apps.who.int/gho/data/node.main.A1075?lang=en (accessed 28 November 2014).

  7. f

    Age-standardized disability-adjusted life years (DALYs) for alcohol use disorders, per 100 000 population. Source: http://apps.who.int/gho/data/node.main.A1218?lang=en (accessed 28 November 20140.

Africa [52–53]42.0 (15.2, 51.4)16.3 (6.4, 28.8)30.0 (11.1, 40.9)6.4 (2.7, 11.3)1.6 (0.4, 2.9)4.0 (1.4, 7.0)15.4 (5.9, 36.6)4.1 (0.4, 17.3)11.8 (4.6, 31.0)5.4 (1.4, 8.8)0.7 (0.1, 1.6)3.0 (0.7, 5.2)97 (57, 137)
Caribbean, central and northern America [23]66.8 (59.1, 70.3)43.4 (35.9, 49.2)55.0 (47.4, 59.8)9.8 (7.7, 12.4)3.9 (2.5, 4.7)6.8 (5.2, 8.2)21.0 (14.6, 31.9)6.0 (3.0, 14.7)15.0 (9.8, 24.5)8.0 (7.8, 8.2)3.1 (3.1, 3.2)5.6 (5.4, 5.7)553 (482, 600)
South America [12]69.6 (62.5, 70.2)47.6 (41.3, 49)58.2 (51.8, 59.4)12.1 (9.8, 13.4)4.2 (3.6, 5.2)8.1 (6.8, 8.9)18.1 (13.5, 35.0)3.2 (1.6, 10.8)13.2 (8.2, 23.9)8.1 (8.0, 8.4)3.1 (3.1, 3.2)5.6 (5.5, 5.7)582 (465, 672)
Central, southern and western Asia [30–31]13.9 (7.5, 49.4)4.6 (3.4, 15.0)9.8 (5.8, 37.2)3.6 (1.2, 7.3)0.4 (0.1, 1.3)2.1 (0.7, 4.3)3.1 (0.8, 29.6)0.5 (0.2, 2.6)2.3 (0.6, 19.9)1.6 (0.5, 8.1)0.3 (0.1, 1.8)1.1 (0.3, 4.9)146 (58, 232)
Eastern and south-eastern Asia [16]48.5 (19.6, 57.9)28.8 (8.1, 33.9)38.4 (14.6, 45.5)9.4 (1.8, 12.0)1.0 (0.1, 2.2)5.5 (1.0, 7.1)9.6 (4.4, 35.2)0.8 (0.4, 5.3)6.6 (2.9, 24.3)6.4 (2.6, 8.8)0.9 (0.5, 1.4)3.8 (1.6, 4.8)280 (130, 550)
Eastern Europe [10]73.8 (72.7, 86.3)62.0 (60.6, 72.7)67.7 (66.2, 79.8)21.3 (19.5, 24.4)7.2 (6.0, 8.1)13.6 (12.9, 15.5)50.0 (32.1, 58.0)17.8 (8.6, 27.9)32.5 (23.9, 43.5)13.7 (8.8, 30.1)2.4 (1.5, 6.2)8.2 (5.2, 17.7)707 (447, 1137)
Northern Europe [10]74.7 (73.7, 88.3)62.6 (61.6, 79.4)68.4 (67.1, 84.4)16.4 (12.4, 18.1)6.6 (5.2, 7.2)11.5 (8.8, 12.3)44.4 (40.9, 64.1)23.3 (19.8, 33.7)34.7 (31.9, 49.6)14.3 (10.5, 17.8)3.5 (3.1, 6.0)9.3 (7.0, 11.5)727 (504, 978)
Southern Europe [12–13]72.2 (69.0, 73.4)58.5 (46.4, 62.8)66.0 (57.2, 68.0)14.6 (10.4, 18.2)5.9 (3.7, 7.1)10.3 (7.0, 12.4)18.4 (17.2, 35.2)2.7 (2.3, 18.2)11.4 (10.8, 27.7)8.8 (6.8, 9.1)2.1 (1.7, 2.5)5.5 (4.3, 5.7)350 (236, 418)
Western Europe [7–8]92.1 (82.2, 95.0)83.6 (78.5, 92.9)88.2 (80.3, 93.9)15.4 (15.0, 16.8)6.4 (6.3, 7.1)11.0 (10.3, 11.9)38.9 (23.6, 56.5)14.1 (7.6, 27.0)25.6 (15.6, 41.7)9.4 (9.1, 14.3)2.8 (2.4, 3.4)6.1 (5.8, 8.7)464 (406, 514)
Oceania [11–15]50.3 (44.2, 55.8)30.9 (19.4, 34.7)34.6 (31.8, 40.7)5.9 (3.1, 13.2)0.6 (0.4, 2.6)3.3 (1.7, 7.9)35.8 (20.9, 59.8)10.9 (6.3, 18.0)26.4 (13.0, 37.1)7.6 (7.4, 7.6)1.4 (1.4, 1.4)4.5 (4.4, 4.6)248 (161, 287)
Least developed countries [46–47]34.1 (12.4, 49.0)14.5 (3.8, 27.4)24.4 (7.9, 38.4)4.5 (1.4, 10.1)0.9 (0.1, 2.3)2.5 (0.7, 6.4)10.6 (3.6, 23.6)1.9 (0.3, 13.2)7.6 (2.8, 20.3)4.6 (1.4, 7.6)0.6 (0.1, 1.4)2.5 (0.8, 4.5)97 (56, 153)
Other countries [139–143]62.0 (46.6, 73.1)38.5 (18.9, 60.6)49.9 (34.6, 66.3)10.8 (6.6, 15.2)3.4 (1.1, 5.5)7.0 (3.8, 10.3)22.6 (12.9, 42.1)5.3 (1.4, 16.3)16.1 (8.7, 31.3)8.0 (5.2, 9.1)1.9 (0.9, 3.1)5.3 (3.2, 5.7)378 (158, 571)
Global [186–190]55.5 (30.2, 70.4)32.0 (11.8, 49.5)43.5 (20.9, 60.9)9.8 (4.4, 13.9)2.5 (0.5, 4.9)6.5 (2.5, 9.2)18.7 (9.4, 40.9)3.7 (0.8, 14.9)13.0 (6.1, 30.6)7.8 (3.5, 8.9)1.5 (0.5, 2.9)4.9 (2.0, 5.6)257 (114, 524)

The column ‘Prevalence of consumption’ indicates the proportion of adults (aged 15 years or more) who consumed any alcohol in the previous 12 months, by gender and for the total adult population. From these data it is estimated that around 43% of adults globally (approximately 2.1 billion people) drink alcohol (Table 3). There is considerable regional variation, from 9.8% in central, southern and western Asia to 88.2% in western Europe. In all regions drinking is less prevalent among females compared with males. Alcohol consumption is also less prevalent in the group of least developed countries compared with countries not listed in this group.

Of this population of adults who consumed any alcohol in the previous 12 months, the proportion with heavy episodic drinking in the past 30 days is presented, also broken down by gender. Heavy episodic drinking is defined as consumption of at least 60 g or more of alcohol on at least one occasion. This level of consumption would be expected to result in significant intoxication, and is a pattern of drinking most likely to be associated with injury, including that arising from motor vehicle accidents and violent behaviour. Globally, approximately 13% of people who drink alcohol have heavy episodic consumption. Again, there is regional variation in this indicator, and heavy episodic drinking is more common among males compared with females, and less common in the group of least developed countries.

The average per-capita consumption of alcohol (in litres per person per year) is given because the volume of alcohol consumed is a determinant of alcohol-related harm [4]. The average annual per-capita consumption of alcohol follows the same pattern as the prevalence of consumption and the prevalence of heavy episodic drinking: globally, alcohol consumption is a median of 6.5 litres per person per year.

Disability-adjusted life years (DALYs) provide an approach to estimating the impact of health conditions and injuries by combining estimates of premature mortality and years lived with disability [5]. The data on DALYs associated with alcohol use are derived from substantial international work. As shown in Table 3, globally approximately 257 DALYs per 100 000 population can be attributed to alcohol use disorders (2570 per million), with regional estimates ranging from 97 per 100 000 population in Africa to 727 per 100 000 population in northern Europe. As with other data, the DALY estimates show that alcohol has less impact in the group of least developed compared with other countries.

People with alcohol use disorders are most likely to be consuming alcohol in large quantities over extended periods of time and constitute a subgroup of the population most likely to experience harmful effects from alcohol. Alcohol use disorders in themselves can be considered a harmful effect of alcohol consumption. Alcohol use disorders comprise both harmful use and dependence. An estimated 4.9% of the world's adult population (approximately 240 million people) suffered from alcohol use disorders in the previous 12 months (Table 3). As with alcohol consumption, alcohol use disorders are more prevalent among males (7.8% globally compared with 1.5% in females).

Tobacco

Summary data on the prevalence of tobacco smoking, and deaths attributed to tobacco, are given in Table 4. These data are derived from the WHO website (the Global Health Observatory), with specific sources indicated in the footnotes to Table 4.

Table 4. Tobacco smoking and related harms.
Regiona [range of number of countries with data]Current smoking, adults, %bCurrent users of tobacco, youth population, %c% Deaths due to tobaccod
MaleFemaleBoth sexesMaleFemaleBoth sexesMaleFemale
  1. Based on data from the WHO Global Health Observatory, with specific sources given below for each indicator. All data are median (first, third quartiles) values.

  2. a

    Countries allocated to geographic regions and group of least developed countries based on United Nations Statistics Division listing (http://unstats.un.org/unsd/methods/m49/m49regin.htm#ftnb). Numbers in square brackets indicate the number of countries in each grouping with data, showing the range for each indicator, or a single number if it was the same across all indicators. NC indicates that there were insufficient data for calculation of regional values (data available from fewer than three countries).

  3. b

    Current smoking of any tobacco product, adults aged 15 years and older, age-standardized rate, by gender. ‘Tobacco smoking’ includes cigarettes, cigars, pipes or any other smoked tobacco products. ‘Current smoking’ includes both daily and non-daily or occasional smoking. Source: http://apps.who.int/gho/data/node.main.1250?lang=en (accessed 28 November 2014).

  4. c

    Current users of any tobacco product, percentage of total youth population aged 13–15 years. Current users of any tobacco product are defined as those that consumed any smokeless or smoking tobacco product at least once during the last 30 days prior to the survey. Source: http://apps.who.int/gho/data/node.main.1259?lang=en (accessed 28 November 2014).

  5. d

    Proportion of deaths in population aged 30 years and older attributable to tobacco, by gender, estimated from 2004 mortality data. Detailed information on calculation of the mortality rates available from the WHO Global Report Mortality Attributable to Tobacco, available from http://whqlibdoc.who.int/publications/2012/9789241564434_eng.pdf?ua=1 (accessed 28 November 2014); summary data also available from www.tobaccoatlas.org

Africa [23–53]23.0 (16.0, 30.5)3.0 (2.0, 5.0)13.0 (9.5, 17.5)20.2 (14.2, 26.3)11.5 (8.1, 18.3)15.3 (11.5, 23.0)4.0 (3.0, 7.5)0 (0, 2.0)
Caribbean, central and northern America [11–23]20.0 (13.0, 24.0)4.0 (2.0, 8.0)13.0 (8.0, 16.0)21.8 (18.1, 25.3)15.6 (12.8, 20.0)18.7 (14.8, 23.7)8.0 (4.0, 10.0)5.0 (1.8, 8.0)
South America [8–12]30.0 (27.5, 39.3)14.5 (6.5, 20.3)21.0 (17.3, 28.8)25.0 (21.0, 28.3)20.6 (16.1, 29.2)22.1 (19.3, 28.5)11.0 (8.0, 15.0)5.0 (2.0, 8.0)
Central, southern and western Asia [23–28]37.0 (31.0, 42.0)4.0 (2.0, 9.0)23.0 (16.0, 26.0)14.5 (11.2, 25.2)8.1 (4.3, 12.8)11.4 (7.6, 18.6)15.0 (12.3, 23.5)3.0 (1.0, 8.0)
Eastern and south-eastern Asia [12–14]45.0 (39.0, 47.8)3.5 (2.3, 6.8)23.5 (22.0, 26.8)22.5 (7.5, 31.7)7.5 (4.0, 13.3)15.3 (5.6, 22.6)19.5 (16.8, 22.5)12.0 (10.3, 15.8)
Eastern Europe [10]41.5 (38.0, 49.3)22.0 (13.3, 28.0)30.5 (28.8, 36.8)28.2 (24.7, 30.5)24.5 (19.3, 31.7)27.1 (23.1, 29.4)26.0 (23.5, 28.5)5.5 (3.5, 10.5)
Northern Europe [3–10]28.0 (23.5, 43.0)22.0 (20.0, 25.5)27.0 (23.0, 31.5)38.4 (33.8, 41.8)28.8 (27.8, 33.9)33.7 (30.8, 37.6)22.0 (16.0, 25.3)11.0 (5.5, 20.3)
Southern Europe [8–11]34.5 (30.8, 44.5)24.0 (17.3, 27.8)28.0 (24.8, 33.5)16.6 (11.1, 17.5)11.1 (7.4, 21.8)12.6 (10.8, 20.4)25.0 (24.0, 27.0)7.0 (3.0, 8.0)
Western Europe [0–8]33.0 (30.5, 40.8)24.0 (22.8, 35.8)28.5 (26.0, 38.5)NCNCNC22.0 (19.5, 27.3)8.5 (5.8, 10.0)
Oceania [9–15]43.0 (32.3, 52.8)19.0 (11.0, 29.5)29.5 (20.8, 43.5)34.1 (22.3, 53.7)32.7 (20.0, 40.1)35.1 (21.8, 47.0)7.0 (4.0, 13.0)8.5 (5.0, 13.8)
Least developed countries [27–47]25.0 (16.0, 42.0)3.0 (2.0, 7.0)14.0 (10.0, 25.0)20.4 (13.0, 26.4)11.6 (7.4, 19.6)16.6 (10.6, 23.2)4.0 (3.0, 9.0)2.0 (0, 8.0)
Other countries [109–132]34.0 (25.5, 43.0)9.0 (3.0, 21.0)23.0 (17.0, 29.0)21.5 (15.0, 28.2)14.5 (8.2, 22.2)18.1 (12.0, 25.8)14.0 (7.3, 23.0)6.0 (3.0, 11.0)
Global [136–179]32.0 (23.3, 43.0)7.0 (3.0, 19.8)22.5 (15.0, 27.0)20.9 (14.5, 27.8)13.2 (7.9, 21.5)17.6 (11.8, 24.9)11.0 (5.0, 22.0)6.0 (2.0, 10.0)

Any level of tobacco smoking is associated with a risk of harmful effects. Hence, Table 4 reports current smoking of any tobacco product as a proportion of the adult population aged 15 years and older without distinguishing between the frequency of use. Data for the youth population (aged 13–15 years) are a little different, in that ‘use of tobacco’ includes smokeless or smoking tobacco. The prevalence of tobacco use in the youth population is an indication of probable trends in smoking among the adult population as this cohort of youth becomes older.

Approximately 22.5% of adults globally smoke tobacco, equating to approximately 1 billion people. While there is regional variation, the extent of this variation is less than is the case with alcohol, with the prevalence of tobacco smoking among adults ranging from a median of 13% in Africa, the Caribbean, central and northern America to 29.5% in Oceania. Like alcohol consumption, tobacco smoking is less prevalent among females (7% compared with 32% for males). Compared with alcohol, there is less difference in the prevalence of tobacco smoking in the group of least developed countries (14%) compared with other countries (23%).

The final columns of Table 4 give the proportion of deaths in 2004 (the most recent year for which this kind of figure is available) that were attributable to tobacco by gender: a median of 6% (1st quartile 2.0%, 3rd quartile 10.0%) for females and a median of 11% (1st quartile 4.0%, 3rd quartile 22.0%) for males.

Data on DALYs attributable to tobacco smoking at a country level were not available when this review was compiled. Such estimates at a global level have been made by the Global Burden of Diseases project [1] and are considered in the Discussion.

Unsanctioned psychoactive drug use

Data on unsanctioned drug use are limited. This is likely to be due in part to the illicit status of many drugs making it harder to monitor use, and in part to low prevalence reducing the capacity of surveys to determine use accurately. The limitations are apparent from Table 5, where a number of regional measures were unable to be calculated due to missing data.

Table 5. Unsanctioned psychoactive drug usea and related harms.
Regionb [range of number of countries with data]CannabiscOpioid-typecCocaine-typecAmphetamine-typecEcstasycHIVdInjectingePrevalence in injecting drug users, %fDALYs gDeaths per million adultsh
HIVHepatitis C
  1. Based on data from the World Drug Report and WHO Global Health Observatory, with specific sources given below for each indicator. All data are median (first, third quartiles) values.

  2. a

    Unsanctioned psychoactive drug use refers to the use of psychoactive drugs whose possession and/or supply is illegal in most jurisdictions or prescription opioids that are being used in an unsanctioned way.

  3. b

    Countries allocated to geographic regions and group of least developed countries based on United Nations Statistics Division listing (http://unstats.un.org/unsd/methods/m49/m49regin.htm#ftnb). Numbers in square brackets indicate the number of countries in each grouping with data, showing the range for each indicator, or a single number if it was the same across all indicators. NC indicates there were insufficient data for calculation of regional values (data available from fewer than three countries).

  4. c

    Annual prevalence of use of unsanctioned drug use, by type, as a percentage of the population aged 15–64 years (but with some minor variation of age range between countries). Dates of estimated prevalence range from 2002 to 2012. ‘Unsanctioned’ drug use includes use of illicit drugs and use of pharmaceutical preparations for non-medical purposes or other than as prescribed. ‘Opioids’ includes illicit preparations of opiates (heroin, opium) and non-medical use of prescription opioid drugs. Source: http://www.unodc.org/wdr2014/ (accessed 27 June 2014).

  5. d

    Prevalence of HIV among adults aged 15–49 years, percentage of population in that age group, 2012 estimates. Source: http://apps.who.int/gho/data/node.main.622?lang=en (accessed 28 November 2014).

  6. e

    Prevalence of injecting drug use among adults aged 15–64 years, percentage. Dates of estimates range from 1996 to 2012. Source: http://www.unodc.org/wdr2014/ (accessed 27 June 2014).

  7. f

    Prevalence of HIV and hepatitis C among injecting drug users, percentage. Dates of HIV estimates range from 1997 to 2012; dates of hepatitis C estimates range from 2003 to 2011. Source: http://www.unodc.org/wdr2014/ (accessed 27 June 2014).

  8. g

    Age-standardized disability-adjusted life years (DALYs) for drug-use disorders, per 100 000 population. Source: http://apps.who.int/gho/data/node.main.A1218?lang=en (accessed 28 November 2014).

  9. h

    Drug-related mortality per million population aged 15–64 years. Dates of estimates range from 2002 to 2012. Source: http://www.unodc.org/wdr2014/ (accessed 27 June 2014).

Africa [1–51]3.0 (2.2, 6.0)0.2 (0.1, 0.3)0.2 (0, 0.7)0.5 (0.1, 1.2)0.2 (0, 0.3)2.1 (1.0, 5.6)0.1 (0, 0.7)8.2 (6.2, 20.6)62.7 (50.2, 94.5)71 (67, 85)NC
Caribbean, central and northern America [2–22]4.8 (1.3, 8.4)0.2 (0.1, 0.7)0.8 (0.5, 1.1)0.8 (0.4, 1.2)0.2 (0.1, 0.3)0.7 (0.3, 1.6)0.8 (0.1, 1.2)6.2 (5.8, 12.9)73.4 (69.1, 96)125 (76, 187)8.5 (4.2, 132.7)
South America [2–12]3.6 (1.6, 4.8)0.1 (0, 0.3)0.7 (0.3, 1.0)0.4 (0.1, 0.5)0.1 (0, 0.2)0.5 (0.4, 0.7)0.3 (0.2, 0.5)10.5 (5.2, 14.3)NC323 (139, 368)3.2 (2.2, 21.2)
Central, southern and western Asia [6–26]3.2 (2.2, 4.2)0.4 (0.2, 1.4)0 (0, 0.2)0.2 (0.1, 0.4)0.4 (0.2, 1.0)0.2 (0.1, 0.3)0.2 (0, 0.6)3.9 (0.3, 9.5)40.0 (24.0, 51.4)85 (65, 255)8.5 (2.5, 21.3)
Eastern and south-eastern Asia [3–5]0.7 (0.3, 1.1)0.2 (0.1, 0.6)0 (0, 0.1)0.4 (0.2, 1.0)0.2 (0.1, 0.3)0.4 (0.2, 0.7)0.3 (0, 0.5)13.4 (8.7, 21.9)67.1 (59.5, 77.1)78 26, 138)22.6 (21.8, 35.7)
Eastern Europe [3–10]3.2 (1.0, 3.7)0.1 (0.1, 0.7)0.2 (0.1, 0.3)0.4 (0.1, 0.7)0.5 (0.2, 0.7)0.7 (0.4, 0.9)0.5 (0.3, 1.2)7.3 (0.5, 18.0)47.8 (22.6, 69.2)93 (25, 237)13.9 (5.9, 29.1)
Northern Europe [0–12]4.9 (3.5, 6.0)0.6 (0.3, 0.8)0.8 (0.3, 1.5)0.8 (0.5, 1.0)0.5 (0.3, 1.2)NC0.3 (0.3, 0.8)3.4 (1.9, 10.8)65.8 (54.1, 73.0)91 (59, 162)76.6 (42.1, 113.9)
Southern Europe [0–13]2.9 (1.7, 4.3)0.4 (0.3, 0.5)0.5 (0.3, 0.7)0.3 (0.1, 0.7)0.6 (0.3, 0.8)NC0.2 (0.1, 0.4)1.4 (0.4, 9.1)36.5 (28.7, 51.9)149 (116, 232)15.5 (6.9, 30.8)
Western Europe [0–9]5.2 (4.8, 7.0)0.3 (0.2, 0.5)0.9 (0.8, 1.0)0.5 (0.2, 0.7)0.5 (0.3, 0.9)NC0.3 (0.2, 0.6)4.2 (1.9, 7.2)58.7 (41.4, 63.8)162 (99, 205)17.0 (3.2, 23.2)
Oceania [2–14]10.3 (5.1, 14.6)NCNCNCNCNCNCNCNC36 (32, 39)NC
Least developed countries [2–45]3.2 (1.5, 4.3)0.2 (0.1, 0.4)NC0.2 (0.1, 1.0)0.2 (0.1. 0.3)1.2 (0.5, 2.8)0 (0, 0.2)7.1 (6.3, 22.5)49.8 (36.9, 80.5)70 (66, 84)NC
Other countries [65–136]3.5 (1.6, 5.3)0.3 (0.1, 0.6)0.5 (0.2, 0.9)0.5 (0.2, 0.8)0.3 (0.1, 0.6)0.5 (0.3, 1.4)0.3 (0.1, 0.6)5.9 (1.4, 12.2)52.6 (36.5, 67.9)100 (62, 213)17.9 (5.3, 41.1)
Global [72–181]3.5 (1.6, 5.2)0.2 (0.1, 0.6)0.5 (0.2, 0.9)0.5 (0.2, 0.8)0.3 (0.1, 0.5)0.7 (0.3, 2.1)0.3 (0.1, 0.5)6.3 (1.8, 12.5)52.6 (36.5, 67.9)83 (63, 173)17.3 (5.7, 40.8)

The data in Table 5 on the prevalence of unsanctioned drug use were drawn from the World Drug Report 2014 [6]. For some countries data were available on the use of ‘opiates’ (heroin, opium) and the use of prescription opioid drugs, but the number of countries for which data on these subsets of opioid drugs were reported were insufficient for meaningful analysis. Table 5 therefore reports only a single category of opioid-type drugs which would include use of illicit preparations (heroin, opium) and non-medical use of prescription preparations.

Cannabis is the most prevalent drug that is mainly subject to unsanctioned use, followed by cocaine-type and amphetamine-type stimulants. Globally, approximately 3.5% of adults (174 million people) use cannabis, with use most prevalent in Oceania (10.3% of adults). Other drugs included in Table 5 are used by fewer than 1% of the adult population.

As indicated in Table 5, approximately 0.3% of the world's adult population (15 million people) inject psychoactive drugs. One of the major harmful effects of unsanctioned drug use is the transmission of blood-borne viruses through injecting drug use. Hence, data on the prevalence of HIV infection in the general population, the prevalence of injecting drug use, and the prevalence of HIV and hepatitis C among injecting drug users are included in Table 5. These data were obtained from the World Drug Report and the WHO Global Health Observatory, as indicated in the footnotes to Table 5. The dates on which estimates of HIV and hepatitis C estimates were made were highly variable. Because injecting drug use is a very efficient means of transmission of blood-borne viruses, epidemics of HIV and hepatitis C can develop very quickly among people who inject drugs. The extent to which these data reflect the current situation is unclear.

Finally, Table 5 includes drug-related DALYs, which accounts for aspects such as episodes of psychosis and schizophrenia associated with use of cannabis and amphetamines, and drug-related deaths. Unsanctioned psychoactive drug use accounts for an estimated 83 DALYs and 17.3 deaths per million population aged 15 64 years.

Gambling

Based on the listing of gambling studies from the Alberta Gambling Research Institute (http://www.abgamblinginstitute.ualberta.ca/LibraryResources/ReferenceSources/PrevalenceInternational.aspx), the median (1st quartile, 3rd quartile) proportion of the adult population who engaged in some form of gambling (other than buying raffle tickets) in the past year was 65.3% (54%, 75%). ‘Problem gambling’ (the definition of which is variable but generally reflects some loss of control over gambling) is much less prevalent at 1.5% (0.9%, 2.8%) of the adult population (Table 6).

Table 6. Prevalence of gambling by country.a
 YearAge (years)% Past yearb% Problem gamblingc
  1. a

    The data included in this table are generally the most recent available for each country, with year indicating the time of assessment. Where data were available for a particular country from multiple years, in some instances the data were selected on the basis of sample size rather than most recent data. Source: Alberta Gambling Research Institute: http://www.abgamblinginstitute.ualberta.ca/LibraryResources/ReferenceSources/PrevalenceInternational.aspx.

  2. b

    Prevalence of any gambling (excluding raffles) in past year (% of population).

  3. c

    Standardized problem gambling prevalence (% of population).

Australia199918+823.9
Belgium200616–9959.72.8
Brazil2005–0614+ 0.9
Canada2006–0718+70.72
Cyprus (northern)200718–65552.2
Czech Republic2012?15–6460 
Denmark200518–74770.5
Estonia200615–74752.1
Finland2011–1215–74781.5
France2009–1018–7547.81.1
Germany201118+63.50.8
Great Britain2006–0716+680.7
Hong Kong201115–64624.4
Hungary200718–6465.31
Iceland200718–7069.41
Isle of Man201216+78 
Italy200818–74542.3
Lithuania200618–6430.12.1
Macau200315–6467.96
Netherlands200416+71.70.5
New Zealand2006–0715+65.31
Northern Ireland201016+75.33.3
Norway201015–70+ 1.4
Singapore201118+473.1
South Africa200818+52.16.4
South Korea201119+41.80.8
Sweden2008–0916–84701.5
Switzerland2006–0714+34.40.4
United States2001–0318+78.41.5

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

Data limitations

The most comprehensive data on addictive behaviours relate to alcohol and tobacco. Data on unsanctioned drug use are more sparse, reflecting the challenges of estimating the prevalence of a behaviour that tends to be hidden due to its largely illicit nature. There may be variation across countries in individuals’ willingness to divulge or report personal drug use. Only use of cannabis is sufficiently prevalent to be detected with confidence in household surveys across diverse countries, but under-reporting may still occur, of course. Multiple sources of information, including data on seizures of illicit drugs, are generally required to gain a picture of trends in unsanctioned drug use. This is the approach taken by the UNODC in compiling the World Drug Report [6]. Limitations in the extent of data on unsanctioned drug use and dependence globally have been noted by others [7]. Data on problem gambling are only available for a minority of countries, but they include major populations of interest, including North America and much of Europe.

While there is substantial information available on the internet concerning the prevalence of addictive behaviours and related harms, this information is scattered over multiple sites and multiple locations within complex websites, such as that of the World Health Organization. Changes to the structure of websites are common, further complicating regular monitoring of this information. Indeed, the scattered nature of the information is one reason for including summary data in this review.

It is even more difficult to find information about the means of data collection, dates of collection and any manipulations by the agency collating the data. Some of this information is available, but much is not, making it difficult to assess the validity or accuracy of the data. Information is skewed towards countries with relatively good reporting capacity; very few data are available for much of Africa and some areas of Asia. In general, it is very difficult to speak with confidence about addictive behaviours in developing countries. The globalized nature of addictive behaviours and the capacity for rapid change in the modern world make it highly desirable for knowledge of global patterns of addiction to be understood more clearly.

Alcohol

Much of the data in Table 3 are derived from the WHO Global survey on alcohol and health conducted in 2012, which resulted in responses from 176 countries. The survey is the basis for the Global Status Report on Alcohol and Health, 2014 [4], which presents a much more detailed analysis of this drug than was possible in this paper. The WHO estimated that world-wide consumption in 2010 was equal to 6.2 litres of pure alcohol per person aged 15 years or older, or 13.5 g of pure alcohol per person per day. This figure is consistent with the median value of 6.5 litres presented in Table 3. In the WHO report [4] it is further noted that a quarter of alcohol consumption (24.8%) was unrecorded; that is, homemade alcohol, illegally produced or sold outside normal government controls. Of the total recorded alcohol consumed world-wide, 50.1% was consumed in the form of spirits. The WHO report also notes the substantial regional variation in the prevalence of alcohol consumption and lower rates of drinking among females, along with the association between economic wealth of a country and higher per-capita consumption of alcohol and greater prevalence of heavy episodic drinking among drinkers.

We were unable to locate online data on deaths related to alcohol consumption, but in the WHO Global Status Report on Alcohol and Health, 2014 [4] it was estimated that in 2012 approximately 3.3 million deaths, or 5.9% of all global deaths, were attributable to alcohol consumption, 7.6% of deaths among males and 4.0% of deaths among females.

Estimates of DALYs attributed to alcohol use disorders are listed in Table 3; the WHO Report estimated that in 2012, 5.1% of the global burden of disease and injury were attributable to alcohol consumption [4]. The Global Burden of Diseases project similarly estimated that 5% of DALYs were attributable to alcohol use [1]. The highest alcohol-attributable fractions of deaths and DALYs were reported in the WHO European Region. The data in Table 3 are consistent with this. Rehm et al. [8] note that most of the deaths caused by alcohol fall into the broad categories of injury, cancer, cardiovascular disease and liver cirrhosis.

While alcohol has been argued to have some beneficial effects on cardiovascular diseases in older age groups at low levels of consumption, this remains highly contentious [9, 10], and the net effect of alcohol consumption on health is clearly detrimental. The costs associated with alcohol amount to more than 1% of the gross national product in high- and middle-income countries, with the costs of social harm constituting a major proportion in addition to health costs [8].

The data in Table 3 provide an estimate that 4.9% of adults globally have an alcohol use disorder (7.8% of men and 1.5% of females). The presence of an alcohol use disorder indicates increased risk of experiencing harm related to alcohol consumption. In a systematic review, Roerecke & Rehm [11] calculated a relative risk of mortality among clinical samples of men with an alcohol use disorder, compared to a control group, of 3.38 [95% confidence interval (CI) = 2.98–3.84]; in women it was 4.57 (95% CI = 3.86–5.42). Relative risks were markedly higher for those aged 40 years or less (ninefold in men, 13-fold in women), while still being at least twofold higher among those aged 60 years or more.

In 2010, alcohol use was one of the three leading risk factors for global disease burden [1].

Tobacco

The data in Table 4 provide an estimate that globally, 22.5% of adults (32% males, 7% females) currently smoke tobacco. Ng et al. [12] derived similar estimates of the prevalence of daily smoking using a modelling approach. Ng et al. estimated age-standardized prevalence of daily tobacco smoking in 2012 to be 31.1% for men and 6.2% for women. These estimates are consistent with the median values obtained from the data summarized in Table 4.

Tobacco smoking is less prevalent than alcohol consumption, but the disease burden due to tobacco smoking is greater. Tobacco smoking (including second-hand smoke) is one of the three leading risk factors for global disease burden, contributing 6.3% (uncertainty interval = 5.5–7.0%) of global DALYs in 2010 [1].

Table 4 presents data on the proportion of deaths in 2004 that were attributable to tobacco smoking. The WHO Global Report: Mortality Attributable to Tobacco, 2012 [13] presents a more detailed analysis. This report notes that globally 12% of all deaths in 2004 among adults aged 30 years and older were attributable to tobacco, with regional estimates ranging from 3% in the African region (as defined by WHO) to 16% in the Americas and European regions. Globally, 5% of all deaths from communicable diseases and 14% of all deaths from non-communicable diseases among adults aged 30 years and older are attributable to tobacco. Within communicable diseases, tobacco use is responsible for an estimated 7% of all deaths due to tuberculosis and 12% of deaths due to lower respiratory infections. Within non-communicable diseases, in a given year tobacco use is responsible for 10% of all deaths from cardiovascular diseases, 22% of all cancer deaths and 36% of all deaths from diseases of the respiratory system. The additional risk of death from cardiovascular system resulting from tobacco use was more likely among younger adults [13].

Unsanctioned psychoactive drug use

Available data from the World Drug Report [6], that are the basis of Table 5, provide only the prevalence of unsanctioned drug use; the prevalence of injecting drug use is included as an indicator of problematic use, but the World Drug Report does not provide the prevalence of drug dependence.

Multiple systematic reviews of unsanctioned drug use were undertaken for the Global Burden of Disease (GBD) project. Based on this work, Degenhardt et al. [7] noted that there is qualitative evidence of unsanctioned drug use and dependence for most countries, but there are gaps in the estimates of prevalence of use. Levels of unsanctioned drug use seem to be highest in high-income countries and in countries near major drug production areas, but data for their use in low-income countries are poor [14]. Degenhardt et al. [15] note that, globally, drug use is not distributed evenly and is not related simply to drug policy, as countries with stringent user-level illegal drug policies did not have lower levels of use than countries with more liberal policies.

Work for the GBD project located estimates of the prevalence of use in 77 countries for amphetamine-type stimulants, 95 for cannabis, 86 for cocaine and 89 for opioids. However, dependence prevalence estimates were located in very few countries: nine for amphetamine-type stimulants, seven for cannabis, five for cocaine and 25 for opioid drugs [7]. Following modelling and imputation of missing data, it was estimated that opioid and amphetamine dependence were the most common forms of unsanctioned drug use that involved dependence in 2010. Although cannabis is by far the most commonly used unsanctioned drug world-wide, the prevalence of cannabis dependence was lower than that for amphetamine-type stimulants and opioid drugs [7]. Estimates of prevalence of amphetamine dependence were highest for Southeast Asia and Australasia; estimates of the prevalence of cocaine dependence were highest for North America (high-income) and Latin America. Australasia had among the highest levels of reported opioid dependence, although the largest populations were in East and South Asia [16, 17]. Where estimates were available, most individuals dependent on drugs were male (64% each for cannabis and amphetamine-type stimulants and 70% each for opioids and cocaine) [18].

Globally, it is estimated that in 2012 between 3.5 and 9.0% of the world population aged 15–64 years had used a psychoactive drug, other than alcohol or tobacco, in an unsanctioned way at least once in the previous year.

Drug use disorders account for 0.8% of global all-cause DALYs. Globally, unsanctioned drug use was identified by the GBD 2010 study as the eighth largest contributor to disability in males [18]. Drug dependence and disease burden are highest in the 20–29-year age group [18]. Two-thirds (69.3%) of all drug disorder DALYs were explained by years lived with disability and 30.7% by years of life lost. While opiate use (e.g. opium and heroin) has remained relatively stable in recent years, misuse of pharmaceutical opioids is increasing and opioid dependence is the greatest contributor to illicit drug burden, accounting for 46% [17]. This finding is attributable to the substantial contribution of opioid drug use to premature mortality, the high disability weight and the comparatively large population of dependent opioid users.

The DALY estimates for opioid drug use were approximately eight times those for cocaine dependence and 4.5 times those for cannabis dependence [18]. In a systematic review undertaken for the GBD 2010, Degenhardt et al. [19] estimated the point prevalence of cannabis dependence globally at 0.19% (95% uncertainty = 0.17–0.21%). Prevalence peaked between 20 and 24 years, was higher in males (0.23%, 95% uncertainty = 0.2–0.27%) than females (0.14%, 95% uncertainty = 0.12–0.16%) and in high-income regions. Cannabis dependence accounted for 0.08% of DALYs globally.

Demand for treatment, and the types of substances being used by people entering treatment, provide additional information on the prevalence of problematic drug use. The World Health Organization has established a database of information on treatment demand and provision of services for substance use, but at present the available information is limited and does not provide an accurate global picture of treatment. Detailed coverage of treatment services was beyond the scope of this review, but it is worth noting that the UNODC has recorded a noticeable increase in the number of people seeking treatment for cannabis use disorders over the past decade, particularly in the Americas, Oceania and Europe. Furthermore, while opioid drugs are the most prevalent primary drug of abuse among those seeking treatment in Asia and in Europe, cocaine is the most prevalent in the Americas [6]. Treatment is an important strategy in the reduction of harms due to substance use in people who are dependent. In this regard the UNODC notes a continuing gap in service provision, with only one in six problem drug users globally having had access to or receiving drug dependence treatment services each year.

Injecting drug use has a notable contribution to burden of disease by increasing the risk of infection with HIV and hepatitis C [18]. In a systematic literature review, Mathers et al. [20] identified injecting drug use in 148 countries. They noted that data for the extent of injecting drug use were absent for many countries in Africa, the Middle East and Latin America. The data have not improved since then, with only 83 countries providing data on the prevalence of injecting drug use for the World Drug Report 2014 [6]. Mathers et al. [20] reported that the largest numbers of injectors were found in China, the United States and Russia, where mid-estimates of HIV prevalence among injectors were 12, 16 and 37%, respectively. HIV prevalence among injecting drug users was 20–40% in five countries (3% of 148 countries identified with injecting drug use) and more than 40% in nine countries (6%). Based on the data from the World Drug Report 2014, 10 countries (12% of those reporting injecting drug use) had HIV prevalence between 20 and 40%, and four (4.8% of countries reporting injecting drug use) had HIV prevalence greater than 40%.

The UNODC, UNAIDS the World Bank and WHO jointly estimate that 0.27% (range = 0.19–0.48%) of the population aged 15–64 years inject drugs. In eastern and south-eastern Europe the rate of injecting drug use is 4.6 times higher than the global average. It is estimated that an average of 13.1% of the total number of people who inject drugs are living with HIV, and more than half the people who inject drugs are estimated to be living with hepatitis C [6].

HIV/AIDS was one of the top six leading causes of death and of years of life lost due to premature mortality in 2010, although there was a small decline in deaths from HIV/AIDS compared to 2006 [21].

The UNODC in the World Drug Report, 2014 [6] estimated drug-related mortality at 40.0 (range = 20.8–49.3) deaths per million aged 15–64 years. Compared with the general population, people who inject drugs have an elevated risk of death. Standardized mortality ratios (95% CI) for people who inject drugs are estimated at 14.68 (13.01, 16.35) globally [22]. Crude mortality rates were higher for males compared to females, but females who inject drugs had a much higher elevation in mortality relative to their age-matched peers in the general population than did males who inject drugs. Drug overdose and AIDS-related mortality were by far the most common causes of death [22].

Gambling

Insufficient data were located for a meaningful analysis of global prevalence of gambling and harms arising from gambling. Data are available for some countries of interest, however. Using a standard definition of problem gambling the prevalence appears to be low, at less than 2%. It is not possible to quantify the harms related to this using available data.

Conclusion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

This paper identifies and discusses a number of online databases that provide information on the global and regional status of addictive behaviours. Data on key indicators of relevance to public health are tabulated. There is relatively good information on the prevalence of use and harms associated with alcohol drinking and tobacco smoking, some information on the prevalence of unsanctioned drug use and limited information on harms related to injecting drug use. However, there is almost no information on the prevalence of dependence on drugs used in an unsanctioned way, a gap that is significant given that it is dependence that primarily drives demand for treatment. Such data may be available at country-level, but the lack of global data leaves a knowledge gap that impedes the capacity for agencies such as WHO, UNODC and UNAIDS and international non-governmental organizations to plan their activities with a view to achieving the greatest possible impact. This suggests an important area of need for future effort and investment to improve the response to addiction world-wide. In particular, it suggests an urgent need to review the quality of data on which global estimates are made and plan for a more consistent approach based on core indicators. The Lisbon consensus on key epidemiological indicators of drug use (http://www.unodc.org/documents/data-and-analysis/statistics/Drugs/lisbon_consensus.pdf) and toolkits developed by the UNODC under the Global Assessment Programme on Drug Abuse (http://www.unodc.org/unodc/en/GAP/) provide a context for such work.

Declaration of interests

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

R.W. undertakes research and consultancy for companies that develop and manufacture smoking cessation medicines.

Acknowledgements

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information

The National Drug Research Institute (S.A.) is supported by funding from the Australian Government under the Substance Misuse Prevention and Service Improvements Grants Fund. The research for this paper was part-funded by the Society for the Study of Addiction. R.W.’s salary is funded by Cancer Research UK; he is a member of the UK Centre for Tobacco and Alcohol Studies. Peer reviewers provided substantial constructive comments on the first draft of this manuscript. The authors thank them for their contributions. The authors would like to thank Bruce Skinner for assistance with data extraction and preparation of the tables.

  1. 1

    We use the term ‘unsanctioned psychoactive drug use’ to refer to use of psychoactive drugs whose possession and/or supply is illegal in most jurisdictions or prescription medications (primarily opioids) that are being used in an unsanctioned way. In this first paper we do not consider ‘legal highs’ or caffeine. Neither do we consider products that are largely restricted to particular regions such as khat. As more data become available for these, they may be added to future papers in this series.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information
  • 1
    Lim S. S., Vos T., Flaxman A. D., Danaei G., Shibuya K., Adair-Rohani H. et al. A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990–2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet 2012; 380: 222460 (2nd corrected version published online 12 April 2013).
  • 2
    Ladouceur R., Boisvert J.-M., Pepin M., Loranger M., Sylvain C. Social cost of pathological gambling. J Gambl Stud 1994; 10: 399409.
  • 3
    Collins D., Lapsley H., Lecavalier J., Single E. Introduction: improving economic data to inform decisions in drug control. Bull Narc 2000; 52: 120.
  • 4
    World Health Organization. Global Status Report on Alcohol and Health. Geneva, Switzerland: World Health Organization; 2014.
  • 5
    Salomon J. A., Vos T., Hogan D. R., Gagnon M., Naghavi M., Mokdad A. et al. Common values in assessing health outcomes from disease and injury: disability weights measurement study for the Global Burden of Disease Study 2010. Lancet 2012; 380: 212943.
  • 6
    United Nations Office on Drugs and Crime (UNODC). World Drug Report 2014. Vienna, United Nations Office on Drugs and Crime; 2014.
  • 7
    Degenhardt L., Bucello C., Calabria B., Nelson P., Roberts A., Hall W. et al. What data are available on the extent of illicit drug use and dependence globally? Results of four systematic reviews. Drug Alcohol Depend 2011; 117: 85101.
  • 8
    Rehm J., Mathers C., Popova S., Thavorncharoensap M., Teerawattananon Y., Patra J. Global burden of disease and injury and economic cost attributable to alcohol use and alcohol-use disorders. Lancet 2009; 373: 22232233.
  • 9
    Roerecke M., Rehm J. Alcohol consumption, drinking patterns, and ischemic heart disease: a narrative review of meta-analyses and a systematic review and meta-analysis of the impact of heavy drinking occasions on risk for moderate drinkers. BMC Med 2014; 12: 182.
  • 10
    Chikritzhs T., Stockwell T., Naimi T., Andreasson S., Dangardt F., Liang W. Has the leaning tower of presumed health benefits from ‘moderate’ alcohol use finally collapsed? Addiction 2015; doi: 10.1111/add.12828 [E-pub ahead of print] (accessed 22 January 2015).
  • 11
    Roerecke M., Rehm J. Alcohol use disorders and mortality: a systematic review and meta-analysis. Addiction 2013; 108: 1562578.
  • 12
    Ng M., Freeman M. K., Fleming T. D., Robinson M., Dwyer-Lindgren L., Thomson B. et al. Smoking prevalence and cigarette consumption in 187 countries, 1980–2012. JAMA 2014; 311: 18392.
  • 13
    World Health Organization (WHO). WHO Global Report: Mortality Attributable To Tobacco. Geneva, Switzerland: World Health Organization; 2012.
  • 14
    Degenhardt L., Hall W. Extent of illicit drug use and dependence, and their contribution to the global burden of disease. Lancet 2012; 379: 5570.
  • 15
    Degenhardt L., Chiu W.-T., Sampson N., Kessler R. C., Anthony J. C., Angermeyer M. et al. Toward a global view of alcohol, tobacco, cannabis, and cocaine use: findings from the WHO World Mental Health Surveys. PLOS Med 2008; 5: e141.
  • 16
    Degenhardt L., Baxter A. J., Lee Y. Y., Hall W., Sara G. E., Johns N. et al. The global epidemiology and burden of psychostimulant dependence: findings from the Global Burden of Disease Study 2010. Drug Alcohol Depend 2014; 137: 3647.
  • 17
    Degenhardt L., Whiteford H., Hall W. D. The Global Burden of Disease projects: what have we learned about illicit drug use and dependence and their contribution to the global burden of disease? Drug Alcohol Rev 2014; 33: 412.
  • 18
    Degenhardt L., Whiteford H. A., Ferrari A. J., Baxter A. J., Charlson F. J., Hall W. D. et al. Global burden of disease attributable to illicit drug use and dependence: findings from the Global Burden of Disease Study 2010. Lancet 2013; 382: 156474.
  • 19
    Degenhardt L., Ferrari A. J., Calabria B., Hall W. D., Norman R. E., McGrath J. et al. The global epidemiology and contribution of cannabis use and dependence to the Global Burden of Disease: Results from the GBD 2010 Study. PLOS ONE 2013; 8: e76635.
  • 20
    Mathers B. M., Degenhardt L., Phillips B., Wiessing L., Hickman M., Strathdee S. A. et al. Global epidemiology of injecting drug use and HIV among people who inject drugs: a systematic review. Lancet 2008; 372: 173345.
  • 21
    Lozano R., Naghavi M., Foreman K., Lim S., Shibuya K., Aboyans V. et al. Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet 2012; 380: 2095128.
  • 22
    Mathers B. M., Degenhardt L., Bucello C., Lemon J., Wiessing L., Hickman M., Mortality among people who inject drugs: a systematic review and meta-analysis. Bull World Health Organ 2013; 91: 10223.

Supporting Information

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aims
  5. Methods
  6. Results
  7. Discussion
  8. Conclusion
  9. Declaration of interests
  10. Acknowledgements
  11. References
  12. Supporting Information
FilenameFormatSizeDescription
add12899-sup-0001-tables.xlsxExcel 2007 spreadsheet100KSupporting info item

Please note: Wiley Blackwell is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.