Birth cohort trends in the global epidemiology of alcohol use and alcohol-related harms in men and women: systematic review and metaregression

Objective: Historically, alcohol use and related harms are more prevalent in men than in women. However, emerging evidence suggests the epidemiology of alcohol use is changing in younger cohorts. The current study aimed to systematically summarise published literature on birth cohort changes in male-to-female ratios in indicators of alcohol use and related harms. Methods: We identified 68 studies that met inclusion criteria. We calculated male-to-female ratios for 3 broad categories of alcohol use and harms (any alcohol use, problematic alcohol use and alcohol-related harms) stratified by 5-year birth cohorts ranging from 1891 to 2001, generating 1568 sex ratios. Random-effects meta-analyses produced pooled sex ratios within these 3 categories separately for each birth cohort. Findings: There was a linear decrease over time in the sex ratio for all 3 categories of alcohol use and related harms. Among those born in the early 1900s, males were 2.2 (95% CI 1.9 to 2.5) times more likely than females to consume alcohol, 3.0 (95% CI 1.5 to 6.0) times more likely to drink alcohol in ways suggestive of problematic use and 3.6 (95% CI 0.4 to 30.3) times more likely to experience alcohol-related harms. Among cohorts born in the late 1900s, males were 1.1 (95% CI 1.1 to 1.2) times more likely than females to consume alcohol, 1.2 (95% CI 1.1 to 1.4) times more likely to drink alcohol in ways suggestive of problematic use and 1.3 (95% CI 1.2 to 1.3) times more likely to experience alcohol-related harms. Conclusions: Findings confirm the closing male-female gap in indicators of alcohol use and related harms. The closing male-female gap is most evident among young adults, highlighting the importance of prospectively tracking young male and female cohorts as they age into their 30s, 40s and beyond.