Additive independent factors that predict risk for alcoholism.

Pedigree and adoption studies have supported a genetic heterogeneity model for alcoholism. Lifetime alcoholism diagnosis in medical-surgical inpatients was reported to increase additively with the presence of Antisocial Personality Disorder (ASP) diagnosis, male gender and family history of alcoholism (FHA). These three risk factors have been shown to have separate genetic transmission. This study tested the predictive strength of these factors in a prospective sample of untreated, nonhospitalized young male (n = 98, mean = 25.2 years) and female (n = 121, mean = 25.5 years) offspring of alcoholic (n = 131) and nonalcoholic (n = 88) parents. NIMH-Diagnostic Interview Schedule items were used to diagnose blindly DSM-III alcohol or drug abuse or dependence. No alcohol- or drug-related behavioral items were used in ASP diagnosis. Parental alcoholism was rated using proband information and Family History Research Diagnostic Criteria. ASP, then gender and finally FHA but not age were significant predictors of DSM-III alcoholism. The log linear analysis improvement chi square was significant at p less than .05 for each variable and the overall goodness of fit of the model was substantial (chi 2 = 13.3, p = .78). Prediction of lifetime alcohol abuse/dependence rates for young adults in a prospective sample was highly significant. These three factors with separate genetic vulnerability increased risk over a lifetime. Male gender increased the risk for alcoholism 1.5 times, FHA 1.5 times and ASP diagnosis 3 times in an independent and additive manner.