Familial resemblance for psychoactive substance use disorders: behavioral profile of high risk boys.

Familial transmission plays an etiologically important role in psychoactive substance use disorders (PSUD). The delineation of the risk status of families is central to implementation of the "high risk paradigm" in studying liability characteristics for PSUD. We have utilized a latent variable approach to characterizing familial resemblance for PSUD which incorporates elements of both the affected parent design, as well as a genetic epidemiologic indicator of familial aggregation of disease. Family resemblance scores were computed for 175 families in which fathers either met diagnostic criteria for PSUD or did not. We then compared the problem behavior profiles of 10-12 year-old boys grouped by familial resemblance for PSUD, and by paternal PSUD only. Boys grouped by paternal PSUD only had higher problem behavior scores than controls across all scales except for somatic complaints. Boys from families that have significant PSUD familial resemblance were characterized by higher scores on measures of externalizing conduct and socialization problems. Thus, the familial resemblance approach was more specific for the externalizing problem behaviors that have been described in longitudinal studies of childhood risk factors for later substance abuse.