Associação entre asma e tabagismo em adolescentes brasileiros

Abstract

Smoking is associated with increased asthma prevalence and more severe symptoms. The aim of this study was to investigate this association in Brazilian adolescents. Cross-sectional study of a national representative sample of school-based adolescents aged 12-17 years from The Study of Cardiovascular Risk in Adolescents (ERICA) stratified by region and conglomerate by schools. Participants answered a self-administered questionnaire including questions about asthma, smoking status, lifestyle and socio-demographic characteristics. Bivariate analysis were performed, between prevalence of current asthma (CA) and other study variables, using chi-square test, prevalence ratio (PR) and 95% confidence intervals (95%CI). Then, generalized linear models were fitted to analyze associations of CA/severe asthma (SA) with smoking adjusted for potential confounders in bivariate analysis (p<0.20). Linear trend chi-square was used to evaluate association between number of household smokers and CA. A total of 66,394 adolescents were included. CA prevalence was 13.2%. There was significant association between CA and all smoking variables: experimentation (PR:1.64, 95%CI:1.46-1.85); current smoking (PR:1.80, 95%CI:1.53 -2.13), frequent smoking (PR:1.91, 95%CI:1.57-2.33) and passive smoking (PR:1.32, 95%CI:1.15-1.52) which remained significant after adjustment. These associations were stronger among those with SA and occurred in all of Brazil´s macroregions. In addition, a progressive and significant increase in prevalence of asthma according to increasing number of household smokers was observed. These findings indicate the need for expansion of public health measures aimed at reducing exposure to different levels of smoking among Brazilian adolescents. Longitudinal studies should be conducted to assess the real impact of smoking on asthma morbidity and development in this age group.