Prior cigarette smoking initiation predicting current alcohol use: evidence for a gateway drug effect among California adolescents from eleven ethnic groups.

Gateway drug theory provides a useful framework for understanding drug use among adolescent populations. Studies have reported a gateway effect of cigarette smoking on alcohol use among adolescents; but there is a lack of knowledge regarding ethnic differences in this effect. Using data from a cross-sectional survey in California, 11,239 subjects (46.3% male) from 31 high schools with at least 25% of total enrollment of Asian and at least 200 students with Asian ancestry entered the analysis. Among them, 6016 were ninth graders (mean age=14.3, S.D.=0.49) and 5223 were twelfth graders (mean age=17.3, S.D.=0.54). After controlling for seven variables, the risk ratio of last 30-day alcohol use among prior smoking initiators vs. noninitiators was 5.82 for non-Hispanic Whites, 4.25 for Blacks, 8.37 for Asian Indians, 3.99 for Chinese, 3.45 for Filipinos, 3.48 for Japanese, 5.41 for Koreans, 7.57 for Vietnamese, 4.02 for Mexicans, 2.64 for South/Central Americans, and 5.95 for adolescents with multiethnic background. Comparison of the 11 ethnic groups indicated that adolescents from different ethnic groups but with similar cultural background had a similar risk level; such pattern existed after controlling for acculturation, parents' monitoring, and school performance. The risk ratio did not differ by gender and grade. There is an association between prior cigarette smoking initiation and current alcohol use among adolescents from different ethnic backgrounds, including those of multiethnicity, which supports the generalizability of gateway drug effect of cigarette smoking on alcohol use. Studies should be conducted to investigate factors attributable to the ethnic variations of this association.