Objective: There has been concern regarding increased substance use during the COVID-19 pandemic, particularly among young adults, but much of this concern stemmed from cross-sectional or short-term data collected early in the pandemic. This study followed a young adult community cohort throughout the first 1.5 years of the pandemic to examine longer-term trends/trajectories in alcohol and cannabis use behaviors.
Method: Beginning before the COVID-19 pandemic (January 2020), 656 young adults completed up to eight surveys on substance use and other behaviors, which extended through August 2021. Multilevel spline growth models estimated changes in alcohol/cannabis use in three segments: (a) from pre-pandemic to April 2020, (b) from April 2020 to September/October 2020, and (c) from September/October 2020 to July/August 2021. Abstainers were removed from the analyses, yielding subsamples for alcohol models (n = 545; M age = 25.6 years; 59.8% female) and cannabis models (n = 303; M age = 25.6; 61.4% female).
Results: Drinking frequency initially increased (3% per month), decreased in the second segment (4% per month), and plateaued in the final segment. Drinking quantity significantly decreased in all three segments: 4% per month in segment one, 3% per month in segment two, and 1% per month in the final segment. Cannabis frequency and quantity showed no significant changes across the first two segments, then significantly decreased in the final segment (3% and 6% per month, respectively). The significant changes for cannabis frequency/quantity were moderated by age, such that older participants had steeper decreases in the final segment.
Conclusions: Findings highlight that young adult alcohol and cannabis use generally declined across the first 1.5 years of the COVID-19 pandemic, contrary to widespread concerns.