Mortality among patients with frequent emergency department use for alcohol-related reasons in Ontario: a population-based cohort study.

BACKGROUND

Little is known about the risk of death among people who visit emergency departments frequently for alcohol-related reasons, including whether mortality risk increases with increasing frequency of visits. Our primary objective was to describe the sociodemographic and clinical characteristics of this high-risk population and examine their 1-year overall mortality, premature mortality and cause of death as a function of emergency department visit frequency in Ontario, Canada.

METHODS

We conducted a population-based retrospective cohort study using linked health administrative data (Jan. 1, 2010, to Dec. 31, 2016) in Ontario for people aged 16-105 years who made at least 2 emergency department visits for mental or behavioural disorders due to alcohol within 1 year. We subdivided the cohort based on visit frequency (2, 3 or 4, or ≥ 5). The primary outcome was 1-year mortality, adjusted for age, sex, income, rural residence and presence of comorbidities. We examined premature mortality using years of potential life lost (YPLL).

RESULTS

Of the 25 813 people included in the cohort, 17 020 (65.9%) had 2 emergency department visits within 1 year, 5704 (22.1%) had 3 or 4 visits, and 3089 (12.0%) had 5 or more visits. Males, people aged 45-64 years, and those living in urban centres and lower-income neighbourhoods were more likely to have 3 or 4 visits, or 5 or more visits. The all-cause 1-year mortality rate was 5.4% overall, ranging from 4.7% among patients with 2 visits to 8.8% among those with 5 or more visits. Death due to external causes (e.g., suicide, accidents) was most common. The adjusted mortality rate was 38% higher for patients with 5 or more visits than for those with 2 visits (adjusted hazard ratio 1.38, 95% confidence interval 1.19-1.59). Among 25 298 people aged 16-74 years, this represented 30 607 YPLL.

INTERPRETATION

We observed a high mortality rate among relatively young, mostly urban, lower-income people with frequent emergency department visits for alcohol-related reasons. These visits are opportunities for intervention in a high-risk population to reduce a substantial mortality burden.