Socioeconomic and Geographic Disparities in Emergency Department Visits due to Alcohol in Ontario: A Retrospective Population-level Study from 2003 to 2017: Disparites Socio-economiques et Geographiques Dans les Visites au Service D'urgence en raison de L'alcool en Ontario: Une etude Retrospective Dans la Population, de 2003 a 2017

Objective: While the overall health system burden of alcohol is large and increasing in Canada, little is known about how this burden differs by sociodemographic factors. The objectives of this study were to assess sociodemographic patterns and temporal trends in emergency department (ED) visits due to alcohol to identify emerging and at-risk subgroups. Methods: We conducted a retrospective population-level cohort study of all individuals aged 10 to 105 living in Ontario, Canada. We identified ED visits due to alcohol between 2003 and 2017 using defined International Classification of Diseases, 10th edition, codes from a pre-existing indicator. We calculated annual age- and sex-standardized, and age- and sex-specific rates of ED visits and compared overall patterns and changes over time between urban and rural settings and income quintiles. Results: There were 829,662 ED visits due to alcohol over 15 years. Rates of ED visits due to alcohol were greater for individual living in the lowest- compared to the highest-income quintile neighbourhoods, and disparities (rate ratio lowest to highest quintile) increased with age from 1.22 (95% CI, 1.19 to 1.25) in 15- to 18-year-olds to 4.17 (95% CI, 4.07 to 4.28) in 55- to 59-year-olds. Rates of ED visits due to alcohol were significantly greater in rural settings (56.0 per 10,000 individuals, 95% CI, 55.7 to 56.4) compared to urban settings (44.8 per 10,000 individuals, 95% CI, 44.7 to 44.9), particularly for young adults. Increases in rates of visits between 2003 and 2017 were greater in rural versus urban settings (82 vs. 68% increase in age- and sex-standardized rates) and varied across sociodemographic subgroups with the largest annual increases in rates of visits in young (15 to 29) low-income women (6.9%, 95%CI, 6.7 to 7.3) and the smallest increase in older (45 to 59) high-income men (2.7, 95%CI, 2.4 to 3.0). Conclusion: Alcohol harms display unique patterns with the highest burden in rural and lower-income populations. Rural-urban and income-based disparities differ by age and sex and have increased over time, which offers an imperative and opportunity for further interventions by clinicians and policy makers.