An adoption study of DSM-IIIR alcohol and drug dependence severity.

ABSTRACT

OBJECTIVE: The objective of this study was to evaluate the role of genetic factors in alcohol and drug dependence at various levels of DSM-IIIR psychoactive substance dependence severity. METHOD: One-hundred-and-ninety-seven adoptees (95 case adoptees with biological parental alcoholism, drug dependence or antisocial personality disorder and 102 control adoptees) were interviewed for the presence of alcohol abuse or dependence and drug abuse or dependence using the Diagnostic Interview Schedule-DIS IIIR. RESULTS: Adoptees with five or more DSM-IIIR criteria for alcohol dependence demonstrated evidence of a genetic effect using this adoption paradigm (odds ratio = 2.3, 95% C.I. (1.1, 4.9)). Adoptees with one or more DSM-IIIR criteria for drug dependence demonstrated a genetic effect (odds ratio = 2.4, 95% C.I. (1.3, 4.4). CONCLUSIONS: This study suggests genetic factors influence the risk for alcohol and drug dependence at different thresholds of severity as determined by DSM-IIIR symptom severity count.