Abstract
BACKGROUND: We examined associations between parental separation during childhood and offspring alcohol involvement, adjusting for genetic and environmental risks specific to parental alcohol (AD) and cannabis/other illicit drug dependence (DD). METHODS: The sample consisted of 1,828 offspring of male twins from the Vietnam Era Twin (VET) Registry, who completed a telephone diagnostic interview. Cox proportional hazards regression analyses were conducted predicting onset of first use, transition from first use to first AD symptom, and transition from first use to AD diagnosis from paternal and avuncular AD and DD history, parental separation, and offspring and family background characteristics. Paternal/avuncular DD/AD was based on the DSM-III-R; offspring and maternal AD were based on DSM-IV criteria. RESULTS: Paternal DD/AD predicted increased offspring risk for all transitions, with genetic effects suggested on rate of transitioning to AD diagnosis. Parental separation was predictive of increased risk for early alcohol use, but a reduced rate of transition to both AD symptom onset and onset of AD. No interactions between separation and familial risk (indexed by paternal or avuncular DD/AD) were found. CONCLUSIONS: Findings highlight the contribution of both parental separation and paternal substance dependence in predicting timing of offspring alcohol initiation and problems across adolescence into early adulthood.