Impact of parental smoking on childhood asthma

OBJETIVE: To evaluate the exposure to environmental tobacco smoke (ETS) of the childhood population in this community and its relationship with asthma symptoms. METHODS: A cross-sectional study was conducted using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire on children and adolescents in this community. The symptoms "wheezing ever", "current asthma", "severe asthma", and "exercise-induced asthma" were defined by this questionnaire. Parental smoking was classified into four mutually exclusive categories: 1) no parent smokes; 2) only the mother smokes; 3) only the father smokes; and 4) both parents smoke. The odds ratio of the prevalence of asthma symptoms according to ETS exposure was calculated using logistic regression. RESULTS: A total of 10,314 children and 10,453 adolescents were included. Over 51% of the children and adolescents were exposed to ETS at home. ETS is associated with a higher prevalence of asthma symptoms, particularly if the mother or both parents smoke. CONCLUSION: The prevalence of ETS is still high in this community, although there has been a decreasing tendency in the last 15 years. ETS is associated with higher prevalence of asthma.