Richard A. Grucza, Ph.D., from the Washington University School of Medicine in St. Louis, and colleagues investigated whether individuals who were legally permitted to drink prior to the age of 21 years remained at elevated risk of suicide and homicide in adulthood. Data were collected from more than 200,000 suicides and 130,000 homicides from individuals born between 1949 and 1972 (the years during which the drinking age was in flux). Unobserved covariates related to MLDA policy exposure were accounted for by implementing a quasi-experimental approach that incorporated fixed effects of U.S. state and birth-year.
The investigators found that MLDA was not associated with homicide and suicide in the population as a whole. However, MLDA policies showed significant interactions with gender for both outcomes, with a significantly higher risk for suicide (odds ratio [OR], 1.12) and homicide (OR, 1.15) among women exposed to permissive drinking age laws. Effect sizes for women born prior to 1960 were not significant, but became stronger for those born after 1960.