Alcohol- and drug-related mortality in Brazil: an ecological and population-based study on changes observed during the COVID-19 pandemic

Background: The COVID-19 pandemic has disrupted healthcare services and intensified socio-economic vulnerabilities, potentially escalating harmful substance use. In Brazil, pre-pandemic mortality from alcohol and drug use was stable. However, the pandemic introduced new risks that may have triggered a significant increase in related deaths. This study, therefore, aims to assess the impact of the COVID-19 pandemic on alcohol- and drug-related deaths in Brazil from 2020 to 2022. Methods: This population-based ecological study analyzed alcohol- and drug-related mortality across Brazil from 2015 to 2022 using data from the Brazilian Mortality Information System (SIM). Temporal trends were examined using Joinpoint regression, while interrupted time-series analyses assessed deviations post-pandemic onset. Spatial variations were visualized using choropleth maps. Findings: Alcohol- and drug-related mortality increased by 18.3% in 2020, 22.4% in 2021, and 26.0% in 2022. The Northeast (2020 = 24.9%; 2021 = 24.0%; 2022 = 31.8%), Southeast (2020 = 18.2%; 2021 = 24.3%; 2022 = 21.0%), and South (2020 = 13.1%; 2021 = 23.6%; 2022 = 35.2%) regions recorded the highest increases, with most states showing significant growth in deaths. We also observed an increase in mortality associated with the use of Psychoactive substances (PAS) in both sexes (male: average annual percentage changes (AAPCs) = 3.6%; female: AAPC = 4.6%), individuals aged 20 to 39 (AAPC = 2.0%), and those aged 60 and above (AAPC = 1.8%). Interrupted time-series analyses confirmed a marked and statistically significant increase in mortality post-March 2020. Interpretation: The findings suggest a collateral epidemic of substance-related deaths fueled by the COVID-19 pandemic's disruptions to harm reduction services, treatment access, and socio-economic stability. These results underscore the urgent need to enhance healthcare systems, reinforce harm reduction services, and develop intersectoral policies targeting social inequalities to mitigate future crises. Funding: This research is part of the PEGA@ACAO study and was funded by the São Paulo Research Foundation (FAPESP, grant #2024/15320-5 and #2025/04763-6); the National Council for Scientific and Technological Development (CNPq, grant #405741/2024-3); and the Coordination for the Improvement of Higher Education Personnel (CAPES, finance code #001).