Factors predicting the onset of adolescent drinking in families at high risk for developing alcoholism.

BACKGROUND: With a longitudinal prospective design, the purpose of this study was 1) to assess, with survival analysis, the age of onset of drinking in relation to family history of alcoholism; 2) to examine the importance of selected neurobiological and psychosocial risk factors in predicting the onset to drink; and 3) to determine if the age of onset of substance dependence problems differed by risk group status.
METHODS: One hundred twenty-five children and adolescents were evaluated annually (N = 638 evaluations), providing up to seven annual waves of longitudinal data. Survival analyses were performed to determine the age of onset of regular drinking and the age of onset for substance abuse/dependence. The age of onset of regular drinking outcome was modeled using familial density of alcoholism and four factors, which included neurobiological indices of development (postural sway and P300), personality characteristics, academic achievement, self-esteem, and trait anxiety.
RESULTS: High-risk children/adolescents showed a significantly earlier age of onset of drinking and an earlier age of onset for substance abuse problems. Familial density of alcoholism predicted an earlier onset of drinking, as did having deficits in reading achievement, reduced P300 (visual and auditory), and greater postural sway for age. Higher scores on the Extraversion scale of the Junior version of the Eysenck Personality Inventory also predicted an earlier onset of drinking.
CONCLUSIONS: Familial density of alcoholism (number of alcoholic first- and second-degree relatives) is an important predictor of adolescent alcohol initiation. Evidence is presented suggesting that part of the familial/genetic variation in outcome may be due to neurobiological factors and temperament.