Alcohol and other drugs in suicide in Canada: opportunities to support prevention through enhanced monitoring

The use of alcohol and other drugs has been identified as a significant factor related to suicide through multiple pathways. This paper highlights current understanding of their contributions to suicide in Canada and identifies opportunities for enhancing monitoring and prevention initiatives. Publications from 1998 to 2018 about suicide in Canada and that referred to alcohol or other drugs were identified using PubMed and Google Scholar. A second literature search restricted to articles including results of toxicology testing was conducted by a librarian. We summarised the literature identified on ecological analyses, attributable fractions and deaths, and research including the results of toxicological analyses. Our literature search yielded 5230 publications, and 164 documents were identified for full-text screening. We summarised the findings from 30 articles. Ecological analyses support the association between alcohol sales, annual per capita alcohol consumption and suicide rates. Based on published estimates, approximately a quarter of suicide deaths in Canada are alcohol-attributable, while the estimated attributable fraction for illegal drugs is more variable. Finally, there is a dearth of literature examining the role of acute alcohol and/or drug consumption prior to suicide based on toxicological findings. The proportion of suicide decedents with drugs or alcohol present at the time of death varies widely. While there is evidence on the role of alcohol and drugs in suicide deaths, there is not a large body of research about the acute use of these substances at the time of death among suicide decedents in Canada. Our understanding of the role of alcohol and other drugs in suicide deaths could be enhanced through systematic documentation, which in turn could provide much needed guidance for clinical practice, prevention strategies and policy initiatives.

The burden of disease attributable to cannabis use in Canada in 2012

BACKGROUND AND AIMS

Cannabis use is associated with several adverse health effects. However, little is known about the cannabis-attributable burden of disease. This study quantified the age-, sex- and adverse health effect-specific cannabis-attributable (1) mortality, (2) years of life lost due to premature mortality (YLLs), (3) years of life lost due to disability (YLDs) and (4) disability-adjusted life years (DALYs) in Canada in 2012.

DESIGN

Epidemiological modeling.

SETTING

Canada.

PARTICIPANTS

Canadians aged ≥ 15 years in 2012.

MEASUREMENTS

Using comparative risk assessment methodology, cannabis-attributable fractions were computed using Canadian exposure data and risk relations from large studies or meta-analyses. Outcome data were obtained from Canadian databases and the World Health Organization. The 95% confidence intervals (CIs) were computed using Monte Carlo methodology.

FINDINGS

Cannabis use was estimated to have caused 287 deaths (95% CI = 108, 609), 10,533 YLLs (95% CI = 4760, 20,833), 55,813 YLDs (95% CI = 38,175, 74,094) and 66,346 DALYs (95% CI = 47,785, 87,207), based on causal impacts on cannabis use disorders, schizophrenia, lung cancer and road traffic injuries. Cannabis-attributable burden of disease was highest among young people, and males accounted for twice the burden than females. Cannabis use disorders were the most important single cause of the cannabis-attributable burden of disease.

CONCLUSIONS

The cannabis-attributable burden of disease in Canada in 2012 included 55,813 years of life lost due to disability, caused mainly by cannabis use disorders. Although the cannabis-attributable burden of disease was substantial, it was much lower compared with other commonly used legal and illegal substances. Moreover, the evidence base for cannabis-attributable harms was smaller.

Crude estimates of cannabis-attributable mortality and morbidity in Canada-implications for public health focused intervention priorities

BACKGROUND

Cannabis is the most commonly used drug in Canada; while its use is currently controlled by criminal prohibition, debates about potential control reforms are intensifying. There is substantive evidence about cannabis-related risks to health in various key outcome domains; however, little is known about the actual extent of these harms specifically in Canada.

METHODS

Based on epidemiological data (e.g. prevalence of relevant cannabis use rates and relevant risk behaviors; risk ratios; and annual numbers of morbidity/mortality cases in relevant domains), and applying the methodology of comparative risk assessment, we estimated attributable fractions for cannabis-related morbidity and mortality, specifically for: (i) motor-vehicle accidents (MVAs); (ii) use disorders; (iii) mental health (psychosis) and (iv) lung cancer.

RESULTS

MVAs and lung cancer are the only domains where cannabis-attributable mortality is estimated to occur. While cannabis use results in morbidity in all domains, MVAs and use disorders by far outweigh the other domains in the number of cases; the popularly debated mental health consequences (e.g., psychosis) translate into relatively small case numbers.

CONCLUSIONS

The present crude estimates should guide and help prioritize public health-oriented interventions for the cannabis-related health burden in the population in Canada; formal burden of disease calculations should be conducted.

Potential Years of Life Lost Due to Premature Mortality Among Treatment-Seeking Illicit Drug Users in Finland

Premature death is a serious public health concern. The primary objective of this study was to examine premature deaths in terms of potential years of life lost (PYLL) in a cohort of 4817 treatment-seeking illicit drug users. Clients' data were linked to the Finnish national cause-of-death register and the follow-up period ranged from 31 January 1997 to 31 December 2010. PYLL before 70 years was calculated for all deaths and cause-specific deaths by gender. We observed 496 deaths (417 males and 79 females) at the end of 2010. The mean age at death was 33.8 years, 34.3 years for males (range 18-68) and 31.4 years for females (range 16-53). Overall, 17,951 life years were lost; 14,898 among males and 3053 among females. The overall PYLL rate for males was more than twice that of females (513.0/1000 vs. 243.7/1000 person-years) but the mean PYLL was higher in females than males (38.6 vs. 35.7 years). Of the total PYLL, 34.8 % was due to accidental overdose, and 24.0 % to suicide. In both genders, accidental overdose and suicide were the two top-ranking causes of PYLL. Premature deaths among drug users are a potential loss to the society. Our findings suggest that measures targeting accidental overdose and suicide are top priorities for reducing preventable loss of life.

Drug policy and the public good: evidence for effective interventions

Debates about which policy initiatives can prevent or reduce the damage that illicit drugs cause to the public good are rarely informed by scientific evidence. Fortunately, evidence-based interventions are increasingly being identified that are capable of making drugs less available, reducing violence in drug markets, lessening misuse of legal pharmaceuticals, preventing drug use initiation in young people, and reducing drug use and its consequences in established drug users. We review relevant evidence and outline the likely effects of fuller implementation of existing interventions. The reasoning behind the final decisions for action might be of a non-scientific nature, focused more on what the public and policy-makers deem of value. Nevertheless, important opportunities exist for science to inform these deliberations and guide the selection of policies that maximise the public good.

Substance-attributable morbidity and mortality changes to Canada's epidemiological profile: measurable differences over a ten-year period

BACKGROUND

Substance use is responsible for a large burden of disease in Canada, however updated data are needed for health care planning and policy development. This study replicates and makes improvements on 1992 estimates of substance-attributable morbidity and mortality for the year 2002. There are two objectives, the main one being to compare the substance-attributable morbidity and mortality in 1992 with 2002 using the same methods of calculation, and the second, to compare the two different methods of estimating the substance-attributable mortality and morbidity in 2002.

METHOD

Estimates of substance-attributable burden were made by combining relative risk data with exposure prevalence data and disease-related mortality and morbidity information from national databases. First, identical relative risk estimates for 1992 were used with the 2002 data in order to draw direct comparisons. In a second analysis, updated relative risk and attributable disease information (post-1992) was used to better estimate the mortality and morbidity for Canada in 2002.

RESULTS

Overall, from 1992 to 2002, there were relative increases in substance-attributable mortality estimates for alcohol and illegal drugs, where the latter relatively increased more; and a relative decrease in tobacco-attributable mortality. In terms of absolute numbers in combined risk factors, deaths and hospital days for those under 70 years of age decreased mainly due to tobacco. Comparisons of the two methods showed that the updated method resulted in more conservative numbers than previous calculations.

INTERPRETATION

There is an unacceptably high burden of substance-attributable disease in Canada in the early 2000s. Exposure changes and epidemiological shifts in population and diseases over the last 10 years have affected where the burden lies, but it is still vital to incorporate policy-based initiatives that have proven to be effective in reducing substance-attributable burden in practice.