GENETIC AND ENVIRONMENTAL-INFLUENCES ON LIFETIME ALCOHOL-RELATED PROBLEMS IN A VOLUNTEER SAMPLE OF OLDER TWINS

Few studies have employed genetically informative designs to study the causes of alcohol-related problems in nonclinical poputations. We rep ort patterns of alcohol abuse in a community-based U.S. volunteer samp le of 3,049 female and 1,070 male twins aged 50 to 96. Significant gen der and age effects were found for self-report measures of current and lifetime alcohol-related problems, with higher prevalence among males and lower frequency among older birth cohorts. Significant associatio ns were found between severity of alcohol abuse (adapted from Feighner criteria) and age of drinking onset, parental history of alcohol prob lems and, among males, lower educational attainment. Model-fitting ana lyses based on data from 650 identical and 479 fraternal twin pairs in dicate substantial family resemblance for a variety of definitions of lifetime alcohol abuse and alcohol problems. The median estimate of ge netic variance across several definitions of alcohol problems was 38.5 %, while that for shared environmental influence was 15.5%. Gender het erogeneity was not found for magnitude of genetic and environmental in fluences, but these comparisons were limited by low statistical power. Findings are discussed with reference to the literature on alcohol ab use among older adults and the genetic epidemiology of alcoholism