Effect of Regional COVID ‐19 Lockdowns on Alcohol Use and Smoking in Two Chilean University Communities: A Difference‐In‐Difference Analysis

Introduction Effects of lockdowns on alcohol use and smoking remain unclear. By exploiting the variation in regional COVID‐19 lockdowns in two Chilean regions, we examined their effect on alcohol use and smoking in two university communities. Methods We conducted a quasi‐experimental study in university communities in two Chilean regions, Coquimbo and Araucanía. Participants were a longitudinal cohort ( n = 896) assessed seven times from July 2020 () to April 2021 (). Outcomes were weekly grams of alcohol use, heavy episodic drinking (HED) and cigarettes smoked per day. Results Lockdown between and was associated with an increase of 15.6 g of alcohol used per week (95% confidence interval 1.8; 29.3) and an increase of 0.3 daily cigarettes smoked (95% confidence interval 0.003; 0.5) at (September 2020), compared to the absence of lockdown. When lockdown reversed at , we found weak evidence of a reduction in alcohol use and smoking in the region under lockdown. We did not observe changes in HED during the study period. Discussion and Conclusions COVID‐19 lockdown appears to result in an initial relative increase in weekly volume of alcohol use and cigarette smoking compared to a region affected by the COVID‐19 pandemic but without lockdown. We did not find evidence of changes in HED. Trial Registration ClinicalTrials.gov , identifier NCT05069090