Abstract
BACKGROUND: We sought to develop an empirical, broad-based developmental model for sex differences in risk for symptoms of alcohol use disorders, here called alcohol problems (APs). METHODS: We assessed 18 risk factors in 5 developmental tiers in both members of 1,377 opposite-sex dizygotic twin pairs from the Virginia population-based twin registry. Analyses were conducted by structural modeling, examining within-pair differences. RESULTS: The best-fitting model explained 73% of the variance in men and 71% in women for last year AP. Forty-nine percent of paths differed significantly across sexes. Ten variables had appreciably different predictive effects on AP in males versus females. Three were stronger in females: familial risk, early-onset anxiety disorders, and nicotine dependence. Seven predictors had a stronger total effect in males: novelty seeking, conduct disorder, childhood sexual abuse, parental loss, neuroticism, low self-esteem, and low marital satisfaction. CONCLUSIONS: In a co-twin control design, which matches sisters and brothers on genetic and familial-environmental background, we found numerous sex differences in predictors of last year AP. Factors that were more prominent in men and in women were diverse, reflecting both internalizing and externalizing psychopathology. The model was slightly more successful at predicting AP in men than in women.