The First Cigarette Smoking Experience and Future Smoking Behaviors Among Adolescents with Different Parental Risk: a Longitudinal Analysis in an Urban Iranian Population.

backgroundLongitudinal research among Iranian adolescent smoking is limited. The current study aimed to investigate (1) the first smoking experience (FSE) and future smoking behaviors of adolescents with different parental risk factors and (2) the association between age of the FSE and future smoking behaviors over a 12-year follow-up.

methodBased on Tehran Lipid and Glucose Study (TLGS) database, 1487 adolescents (12-18 years) with complete baseline parental data were recruited. Using two-step cluster analysis, families were classified as either high or low risk; these were based on parental risk factors including age, education, employment, and smoking status. Participants were examined four times in 12 years and their data were used for survival analysis. After exclusion of 24 cases who were smokers at baseline, Cox proportional hazard modeling was used to evaluate the effect of parental clusters on the FSE in 1463 nonsmoking adolescents who completed all prospective follow-ups. Logistic regression analysis was used to examine the effect of the age of FSE on future smoking behaviors.

resultsThe mean age of adolescents was 14.63 ± 2.07 years at baseline. Adolescents in the high-risk cluster group were 49% more likely to try smoking for their first time, and 55% more likely to smoke in the future. Compared with girls, boys had 83% higher chance of trying their first cigarette. Moreover, 1-year delay in the FSE resulted in 25% reduction in the probability of smoking in the future.

conclusionThe findings show that compared with adolescents living in low-risk families, teenagers living in high-risk families are at greater risk of smoking at an earlier age; therefore, this group could benefit from gender- and culture specific preventive interventions.