Changes in Alcohol, Cannabis, and Tobacco Use Before and After the COVID-19 Pandemic in Adolescents in Catalonia: A Repeated Cross-Sectional Study

This study analyzes the impact of the COVID-19 pandemic on alcohol, cannabis, and tobacco use among adolescents aged 14–19 in Central Catalonia across three periods. Data were obtained from two waves of the DESKcohort project. The first wave (n = 4641) was pre-COVID-19 and the second wave was divided into two phases: post-COVID-19 with restrictions (n = 3478) and post-COVID-19 without restrictions (n = 2900). The prevalence of monthly binge drinking, cannabis use in the last 30 days, and daily tobacco use was calculated. Poisson regression models estimated adjusted prevalence ratios (aPR) comparing two post-pandemic phases to the pre-pandemic baseline. Binge drinking increased during the restrictions among girls [aPR = 1.5 (95%CI: 1.1–2.1)] and boys [aPR = 1.7 (95%CI: 1.3–2.3)]. Cannabis use decreased during restrictions and remained low post-pandemic, especially among girls [aPR = 0.6 (95%CI: 0.5–0.8)] and boys in the 4th Compulsory Secondary Education (CSE) [aPR = 0.4 (95%CI: 0.3–0.6)], and girls in the 2nd Post-Compulsory Secondary Education/Intermediate-Level Training Cycles (PCSE/ILTC) [aPR = 0.7 (95%CI: 0.6–0.9)]. Daily tobacco use also dropped among boys in the 4th year of CSE [aPR = 0.5 (95%CI: 0.3–0.7)] and girls in the 2nd year of PCSE/ILTC [aPR = 0.7 (95%CI: 0.6–0.9)]. The COVID-19 pandemic has created a unique opportunity to reassess patterns of adolescent substance use in a context of sudden social disruption. The findings highlight the need to denormalize alcohol and tobacco use and promote healthier adolescent behavior through education.