[Analysis of factors related to smoking initiation and continued smoking in young adolescents]

To analyse the determining of the acquisition and later consolidation of the tobacco consumption in young adolescents.

Longitudinal study of three years of duration (2000-2002). Subjects were students of secondary education between 13 and 14 years old at the beginning of the study. The research was performed in Gran Canaria Island with a final sample of 745 subjects. Models of conditional binary election were considered for longitudinal data where the dependent variable reflects decisions of the adolescents through time, with regard to the probability of beginning to smoke, "beginning model", and the probability of being occasional or habitual smoker, "experimentation model".

In the last year, 57% of the young teenagers surveyed use tobacco, a 25% more than in the first year, some of them, 9% on a daily basis. In the "beginning model" the determining of the tobacco consumption are interest in studies (odds ratio [OR] = 0.27; 95% confidence interval (CI), 0.08-0.87 and OR = 0.14; 95% CI, 0.03-0.58 for the students having enough and much interest in studies, respectively), to have a smoker as the best friend (OR = 7.44; 95% CI, 2.59-21.4), the alcohol consumption (OR = 11.82; 95% CI, 4.96-28.2 and OR=15.42; 95% CI, 4.68-50.7 for youngs who drink alcohol occasionally or frequently) and having more pocket money (euros per week) (OR = 1.13; 95% CI, 1.07-1.19). For the "experimentation model", to have a smoker as the best friend (OR = 7.01; 95% CI, 2.96-16.5), the alcohol consumption (OR = 5.71; 95% CI, 1.98-16.4 and OR = 5.22; 95% CI, the 1.56-17.5 for youngs who drink alcohol occasionally or frequently) and the number of years since the student started smoking (OR = 1.44; 95% IC, 1.11-1.86).

Our study emphasizes, peer group effect, drinking alcoholic beverages and lack of interest in studies as factors associated to the tobacco consumption.