Fatal drug overdoses more common among lower-income and unemployed Canadians

Canada is facing a drug toxicity crisis, contributing to a rise in overdose deaths. This crisis worsened during the COVID-19 pandemic when opioid-related deaths drastically increased. For efforts to address this crisis to be the most effective, it is important to know who is at a high risk of overdose deaths. Socioeconomic factors, such as income, employment, and education, are known to impact health inequities, including in substance use and associated harms. However, due to a lack of recent data on the topic, we do not know how overdose deaths vary across socioeconomic groups in Canada.

For this study, the researchers wanted to see how drug overdose deaths among Canadians varied by household income, employment status, and education level.

To do this, they used the 2016 Canadian Census Health and Environment Cohort (CanCHEC). This dataset is made up of 8.3 million Canadians who completed the long-form Census in 2016. CanCHEC also links those individuals with a database of Canadian death records up to 2021.

The researchers focused on the 4.6 million respondents who were 25 to 64 years of age when they completed the 2016 Census. 

They identified individuals whose cause of death was recorded as a drug poisoning (whether accidental, intentional or of unknown intent). The term drug poisoning is more commonly known as a drug overdose.

They also collected sociodemographic information for the respondents, which was measured using the Census along three dimensions:

1. household income, with five groups from lowest to highest income
2. employment status and hours worked the previous week
   • not in the labour force (jobless and not seeking work)
   • unemployed (jobless but actively seeking work)
   • working, part-time (less than 30 hours per week)
   • working, full-time (30 to 48 hours per week)
   • working, long hours (49 or more hours per week)
3. highest education level completed
   • less than high school
   • high school diploma
   • some post-secondary below a university degree
   • university degree or higher

Between 2016 and 2021, in the sample of respondents, there were 4,735 drug overdose deaths among women and 9,060 among men.

Rates of drug overdose deaths were highest among:

• those in the lowest group of household income,
• those who were unemployed or out of the labour force, and
• those without a high school degree, 

For both women and men, as socioeconomic status declined over each category (meaning less income, fewer hours of employment, and lower levels of education), drug overdose deaths increased. This graded pattern was similar for both men and women (see table 1).

In some cases, inequities were more pronounced for women than men of the lowest socioeconomic status. For example, women not in the labour force had nearly 10 times the risk of overdose death compared to women with full-time employment. For men not in the labour force, their risk was about six times as high.

This study describes the extent of socioeconomic inequities in overdose deaths among working-age Canadians. Lower-income individuals, those who were unemployed, out of the labour force, or working part-time, and those with lower levels of education were more likely die from an overdose. Public health interventions are needed to address the drug toxicity crisis, including the disproportionate toll this crisis is taking on socioeconomically disadvantaged groups. This data can also provide a baseline to monitor trends in the socioeconomics differences in overdose deaths over time.

A strength of the study includes the large, representative sample. This allows for results that are applicable to the broader working-age population in Canada. Additionally, as death records spanned 2016 to 2021, impacts of the drug toxicity crisis and effects of the COVID-19 pandemic are partly reflected in these results, and provide a timely update of the data on this issue. 

A limitation of the study includes that socioeconomic position was assessed in 2016 and may not reflect changes over time, particularly with the onset of the COVID-19 pandemic and related labour market changes. Employment status and household income can be unstable across the adult life course, which would lead to potentially underestimating the link between drug poisoning and socioeconomic factors. 

Additionally, while the findings suggest socioeconomic status is linked to the risk of overdose deaths, this study cannot infer that it is the cause of these deaths. There may be other factors related to substance use that this study could not account for.