Alcohol consumption, mental health, and the moderating role of social isolation during the COVID-19 pandemic in southern Brazil

OBJECTIVE: Investigate changes in alcohol consumption and the association between maternal depression and anxiety, considering the moderating effect of social isolation during the COVID-19 pandemic, using a population-based cohort from Brazil. METHODS: Data were obtained from the WebCovid-19 study, a web-based follow-up of the 2019 Rio Grande (RS), Brazil, birth cohort, with 1,077 and 1,033 postpartum women participating in waves I and II, respectively. Changes in maternal alcohol consumption were self-reported, while depression and anxiety were assessed using the Edinburgh Postnatal Depression Scale and the Generalised Anxiety Scale. Crude and adjusted negative binomial regression was conducted, including tests for moderation by social isolation. RESULTS: Of the 781 mothers included, 57.3% reported staying home ≥5 days in the last week, and 5.0% increased alcohol consumption during the pandemic. Median depression and anxiety scores were 8.0 (interquartile range - IQR 3-13) and 6.0 (IQR 3-10), respectively. Mothers who increased alcohol consumption had a 5-point (95% confidence interval - 95%CI 3.0-7.0) and 4.2-point (95%CI 2.6-5.9) increase in depression and anxiety scores, respectively. Social isolation duration did not significantly modify the effect of alcohol consumption on mental health. CONCLUSION: Increased alcohol consumption during the pandemic was associated with higher depression and anxiety scores. The hypothesised moderating effect of longer isolation on this association remains a possibility.