Earlier age of smoking initiation may not predict heavier cigarette consumption in later adolescence.

Previous studies suggest that earlier cigarette smoking initiation in adolescence predicts greater cigarette consumption later in adolescence or adulthood. Results from these studies have been used to inform interventions for adolescent smoking. However, previous studies suffer from several important methodological limitations. The objective of the present study was to address these limitations by longitudinally and prospectively examining whether and how age of initiation of smoking among adolescents predicts cigarette consumption by age 16 or 17. Participants completed an in-class survey every 6 months for 2-3 school years. Participants included 395 adolescents (Mean age=14 years at baseline; 53.2% female) from two public high schools in Northern California (Schools A and B) who completed self-report measures of smoking initiation, number of friends who smoke, and number of whole cigarettes smoked by the final survey time point. Adolescents who were older when they first smoked one whole cigarette were 5.3 to 14.6 times more likely in School A and 2.9 to 4.3 times more likely in School B to have smoked a greater number of cigarettes by age 16 or 17. Results suggested that earlier smoking initiation may not lead to heavier cigarette consumption later in time, as has been previously shown. There may be a period of heightened vulnerability in mid- or late adolescence where smoking experimentation is more likely to lead to greater cigarette consumption. Targeting prevention efforts to adolescents aged 14 to 17 years may further reduce smoking initiation among youth, thus limiting subsequent smoking-related morbidity and mortality in adulthood.