Genetic and Environmental Influences on Alcohol Consumption in Middle to Late Life

Objective: Alcohol use is common in older adults and linked to poor health and aging outcomes. Studies have demonstrated genetic and environmental contributions to the quantity of alcohol consumption in mid-to-late life, but less is known about whether these influences are moderated by sociodemographic factors such as age, sex, and educational attainment. This study sought to better understand sociodemographic trends in alcohol consumption across the second half of the life course and their underlying genetic and environmental influences. Method: Primary analyses were based on 64,140 middle-aged or older adult twins (40–102 years) from 14 studies in the Interplay of Genes and Environment Across Multiple Studies consortium. We harmonized a measure of weekly alcohol consumption (in grams of ethanol per week) across all studies. Results: Older age was associated with lower alcohol consumption, primarily for adults over age 75, for individuals with higher education, and for males. Trends were similar across birth cohorts and after excluding current abstainers. At mean age 56, alcohol use was moderately heritable in females (.34, 95% CI [.26,.41]) and more heritable in males (.42, 95% CI [.38,.45]). Heritability was lower in older aged adults and in females with higher education. Conclusions: This study represents the largest twin study of alcohol consumption in middle-aged and older adults. Results highlight that genetic and environmental factors influence alcohol consumption differently across age, sex, and educational attainment and that intervention efforts may need to be tailored based on individuals’ backgrounds.