The Intensity of Adolescent Substance Use Before and After the COVID-19 Pandemic.

Abstract

Adolescent cannabis and alcohol use declined substantially after the COVID-19 pandemic onset in 2020. This study tests whether substance use hardened, defined as an increased proportion of heavy users resulting from overall prevalence declines driven mainly by reductions in light and moderate use. Data come from Monitoring the Future, which annually surveys nationally representative, cross-sectional samples of U.S. adolescents in 8th, 10th, and 12th grades. The analysis includes 252,810 respondents surveyed between 2017 and 2024, with response rates of 86% in 8th grade, 85% in 10th grade, and 76% in 12th grade. The main outcome is lifetime intensity of cannabis and alcohol use, measured as light (1-5), moderate (6-19), and heavier (≥20) occasions of lifetime use. After the pandemic onset, adolescent alcohol use softened notably, whereas cannabis use softened slightly. For alcohol, light use increased significantly across all 3 grades by 3-7 percentage points, moderate use decreased in all 3 grades by 2-4 points, and heavy use decreased by 4 points in 12th grade and 3 points in 10th grade. For cannabis, changes were limited to 10th grade, where light use increased by 3 points, and moderate use decreased by 2 points. These results point to a continued need for prevention policies and programs to achieve further reductions in adolescent cannabis and alcohol use. Current patterns of use are not yet at a hardened stage dominated by heavy users who struggle to quit, where further reductions in prevalence would be achieved primarily through cessation programs.