Pubertal timing and smoking initiation in adolescent females: differences by race.

INTRODUCTION: The purpose of this study was to examine whether (a) early pubertal timing effects on smoking onset existed for both White and Black girls and (b) whether the association between pubertal timing and smoking onset was moderated by race.
METHODS: Participants included 264 girls (14.9 +/- 2.2 years, 164 White, and 100 Black) at the baseline report of a longitudinal study of whom 153 reported smoking and age at first cigarette.
RESULTS: Kaplan-Meier analysis stratified by racial group showed a significant difference between the pubertal timing groups for Black girls only. After accounting for covariates using Cox regression, there was no significant interaction between pubertal timing and racial group. There was a main effect of pubertal timing indicating that late maturers were at significantly lower risk for smoking initiation compared with the early and on-time groups, but the early and on-time groups were not significantly different from each other. DISCUSSION: Results point to equal risk of early smoking onset for early and on-time maturers of both racial groups, indicating the need for smoking prevention in early adolescence for both White and Black females.