Severity of alcohol-related hospitalizations following the onset of the COVID-19 pandemic: a population-based cohort study

Background — Alcohol use and alcohol-attributable hospitalizations increased during the COVID-19 pandemic; however, whether hospitalizations were more severe during the pandemic years is unknown.

Objective — To examine the severity of alcohol-related hospitalizations following the onset of the COVID-19 pandemic.

Design — We conducted a retrospective cohort study of alcohol-attributable hospital admissions between March 2016 and February 2022 in Ontario, Canada.

Participants — Using established databases, we identified residents aged 18 to 105 years with an alcohol-related hospital admission. We excluded patients with a missing or invalid health card and non-Ontario residents.

Exposure — The primary exposure was the onset of the COVID-19 pandemic (March 2020). The study period included two phases: before the pandemic (2016 to 2020) and during the pandemic (2020 to 2022).

Main measures — We used generalized estimating equations with a negative binomial distribution to compare the average length of stay and other secondary outcomes (critical care admissions, in-hospital mortality, 30-day mortality, 1-year mortality, 30-day readmission) during the two study periods.

Key results — We identified 107,030 hospitalizations in the pre-pandemic period and 57,971 in the pandemic period. The mean length of hospital stay was 13.1 days (standard deviation [SD] 43.3) before the pandemic, and 12.1 days (SD 29.7) during the pandemic. After adjustment, length of stay was marginally shorter during the pandemic (relative risk [RR] 0.94; 0.91 to 0.97), driven by shorter mental health admissions. Compared to pre-pandemic, admissions during the pandemic were characterized by an increased risk of 30-day mortality (aRR 1.09; 1.04 to 1.14), 1-year mortality (aRR 1.13; 1.08 to 1.18), 30-day readmission (aRR 1.09; 1.06 to 1.14), and a decreased risk of ICU admission (aRR 0.95; 0.93 to 0.98).

Conclusions — Compared to alcohol-related hospitalizations pre-pandemic, hospital length of stay during the pandemic was slightly shorter. Admissions in more recent years were associated with other increased risks of re-admission and mortality.