RESUMEN
BACKGROUND: Asthma prevalence in adolescents appears to be increasing and determinants are not well established. OBJECTIVE: To determine the association between sex and active smoking with asthma prevalence in adolescents. PARTICIPANTS AND METHOD: In this cross-sectional study 6,922 students, ages 12 to 18 years, residents in an area of northeastern Mexico, were included. We developed a questionnaire based on The International Study of Asthma and Allergies in Childhood (ISAAC) and on The European Community Respiratory Health Survey (ECRHS). The association between sex and active smoking with asthma prevalence was determined using a logistic regression model. RESULTS: Of the total population, 46.3% were males, 7.3% suffered from asthma and 17.3% were cigarette smokers. We found that sex (OR = 0.55; CI 95%: 0.48-0.63) and active smoking (adjusted OR = 1.12; CI 95%: 0.89-1.42) were not associated with asthma prevalence. Females (OR = 1.44; CI 95%: 1.13-1.84) and active smoking (adjusted OR = 1.38; CI 95%: 1.15-1.67) were associated with prevalence of wheezing in the last 12 months, and with prevalence of dry cough at night (OR = 1.53; CI 95%: 1.34-1.76). CONCLUSIONS: Teenager males and active smoking were not associated with asthma prevalence. Females had an association with wheezing in the last 12 months and dry cough at night.