Individual and joint association of adulthood experiences and parental or teacher smoking with adolescent cigarette smoking

INTRODUCTION: One limitation of the minimum legal age (MLA) law, the primary strategy for curbing youth smoking, is the rite-of-passage effect. Adulthood experiences and the behavior of surrounding adults help build ‘adult identity’ among adolescents. We examined the individual association of adulthood experience and joint association with significant adults who smoke with adolescent cigarette smoking. METHODS: A nationally representative cross-sectional sample of 138542 South Korean adolescents aged 12–18 years (mean: 15 years) from the 2014 and 2015 Korea Youth Risk Behavior Survey was used. Adulthood markers used were tall stature, precocious sexual development, independent living, and job experience. Parents and teachers were considered significant adults. Logistic regression analyses and relative risk due to interaction (RERI) calculations were conducted. RESULTS: Tall stature (OR=1.19; 95% CI: 1.08–1.31), precocious sexual development (OR=1.51; 95% CI: 1.36–1.69), independent living (OR=1.24; 95% CI: 1.08– 1.43), and job experience (OR=4.38; 95% CI: 4.14–4.64) were associated with cigarette smoking among study participants. Statistically significant additive interactions were found for parental smoking and job experience (RERI=0.41; 95% CI: 0.06–0.76), teacher smoking and precocious development (RERI=0.71; 95% CI: 0.28–1.15), teacher smoking and independent living (RERI=0.68; 95% CI: 0.11–1.24), teacher smoking, and job experience (RERI=2.12; 95% CI: 1.66– 2.58). CONCLUSIONS: The association between adulthood experience and adolescent cigarette smoking suggests the rite-of-passage effect, which may be strengthened by the MLA law. Raising the MLA to an age much higher than the normative age of adulthood initiation is required. Additionally, targeted intervention for adolescents with both adulthood experience and exposure close to adult smoking are required to curb youth smoking.