High-resolution examination of changes in drinking during the COVID-19 pandemic: Nine-wave findings from a longitudinal observational cohort study of community adults

Few multi-wave longitudinal studies have examined changes in drinking across extended periods of the coronavirus 2019 (COVID-19) pandemic. Using multiple indicators over three years, the current study examined: a) overall drinking changes; b) sex, income, age, and pre-COVID drinking level as moderators of changes; and c) the clinical significance of the observed changes. Using a longitudinal observational cohort design with nonclinical adults from the general community (N = 1395), assessments were collected over nine waves, two pre-COVID (April 2019 and October 2019) and seven intra-COVID (April 2020-April 2022). Drinking was measured as percent drinking days, percent heavy drinking days, and the Alcohol Use Disorders Identification Test (AUDIT) score. Clinically significant changes were defined based on the World Health Organization risk levels. All indicators exhibited significant changes from pre-pandemic to intra-pandemic periods, with drinking changes comprising early pandemic increases followed by subsequent decreases and AUDIT scores consistently declining. Pre-pandemic drinking level substantially moderated all changes. Heavier drinkers exhibited larger decreases compared to other drinking groups. In terms of clinically important changes, ∼10% of pre-pandemic abstinent or low-risk drinkers transitioned to medium- or high-risk status during the pandemic. In contrast, 37.1% of medium-risk drinkers and 44.6% of high-risk drinkers exhibited clinically significant decreases during the intra-pandemic period. Collectively, these findings highlight the multifarious impacts of the pandemic on drinking over time, comprising both increases and decreases in drinking behaviour.