Age at smoking onset and its association with alcohol consumption and DSM-IV alcohol abuse and dependence: results from the National Longitudinal Alcohol Epidemiologic Survey.

The major purpose of this study was to examine the relationship of early onset smoking with lifetime drinking and the subsequent development of DSM-IV alcohol abuse and dependence using a large representative sample of the U.S. general population. Prevalences of lifetime drinking, alcohol abuse and dependence, and their associated severity were compared among smoking groups defined by age at onset of smoking and among nonsmokers. Linear logistic regression analyses were conducted to assess the relationship between age at smoking onset and lifetime drinking, alcohol abuse and dependence, controlling for important covariates. Early onset smoking was a significant predictor of lifetime drinking and the subsequent development of lifetime alcohol abuse and dependence, a relationship that generally remained consistent for males, females, whites and blacks. Early onset smoking was significantly associated with more excessive alcohol consumption and more severe alcohol use disorders relative to late onset smokers and nonsmokers. Early onset smoking was also significantly associated with heavier and longer smoking careers compared to late onset smokers. Implications of these findings are discussed in terms of prevention of adolescent smoking and the need for further research on understanding the mechanisms underlying the associations between early onset smoking and lifetime drinking, alcohol abuse and dependence.