Investigating the association between income inequality in youth and deaths of despair in Canada: a population-based cohort study from 2006 to 2019
Previous studies have shown that so called “deaths of despair” are on the rise in North America. The term was coined by researchers Anne Case and Angus Deaton and is usually defined as deaths due to suicide, drug-overdose and alcohol poisoning or alcohol-related liver-disease.
In their work, Anne Case and Angus Deaton highlight the reduction in life expectancy in the USA due to deaths of despair.
This study examines the association between income inequality and deaths of despair in Canada, specifically among youth.
Suicide has been a leading cause of death in Canada since the 1990s and deaths due to alcohol and other drugs are on the rise.
- From 2000 to 2019, drug-overdose mortality rates have increase from 2.98 to 6.92 per 100,000, and
- Alcohol-related liver disease mortality rates have increased from 3.54 to 4.57 per 100,000.
Income inequality, defined as the differences in income within a given group or area, is a major risk factor for adverse mental health outcomes and death. Adverse mental health is strongly associated both with substance use and suicide.
Evidence on the mechanisms linking income inequality in youth to risk of deaths of despair is limited. The authors of the study mention three main mechanisms recognised in the existing literature:
- Divestment in harm reduction services may result in the closure of supervised consumption sites and an influx in drug overdoses within areas with high income inequality.
- Lack of access or closures of youth-appropriate mental health services within areas with high-income inequality may be associated with increased risk of self-medicating coping behaviours and even suicidality.
- Income inequality may lead to the erosion of social capital, resulting in reducing connectedness, mutual aid and trust between residents within communities and neighbourhoods.
The researchers carried out a population-based longitudinal study of Canadians aged 20 years or younger, using data from the Canadian Census Health and Environment Cohorts. The study sample included 1.5 million Canadians, representing 7.7 million Canadians between the ages of 0 and 19 at baseline.
Results from the survival models demonstrated that income inequality was associated with an increased hazard of:
- Deaths of despair – adjusted hazard rate (AHR): 1.35
- Drug overdose – adjusted hazard rate (AHR): 2.38
- All-cause deaths – adjusted hazard rate (AHR): 1.10
Due to a limited number of cases alcohol-related liver disease was not tested as an independent outcome.
Deaths due to suicide, drug overdose and alcohol-related liver disease, collectively known as ‘deaths of despair’, have been markedly increasing since the early 2000s and are especially prominent in young Canadians. Income inequality has been linked to this rise in deaths of despair; however, this association has not yet been examined in a Canadian context, nor at the individual level or in youth. The study objective was to examine the association between income inequality in youth and deaths of despair among youth over time.
The researchers conducted a population-based longitudinal study of Canadians aged 20 years or younger using data from the Canadian Census Health and Environment Cohorts. Baseline data from the 2006 Canadian Census were linked to the Canadian Vital Statistics Database up to 2019. The researchers employed multilevel survival analysis models to quantify the association between income inequality in youth and time-to deaths of despair.
The study sample included 1.5 million Canadians, representing 7.7 million Canadians between the ages of 0 and 19 at baseline.
Results from the weighted, adjusted multilevel survival models demonstrated that income inequality was associated with an increased hazard of deaths of despair (AHR 1.35); drug overdose (AHR 2.38) and all-cause deaths (AHR 1.10).
Income inequality was not significantly associated with suicide deaths (AHR 1.23).
The results show that higher levels of income inequality in youth are associated with an increased hazard of all-cause death, deaths of despair and drug overdose in young Canadians.
This study is the first to reveal the association between income inequality and deaths of despair in youth and does so using a population-based longitudinal cohort involving multilevel data. The results of this study can inform policies related to income inequality and deaths of despair in Canada.