Trend of self-reported asthma prevalence in Brazil from 2003 to 2013 in adults and factors associated with prevalence.

ABSTRACT

OBJECTIVES: To determine the trend of self-reported asthma diagnosed prevalence and to describe the factors associated with asthma in Brazilian adults. METHOD: Epidemiological cross-sectional study based on databases analysis from three national household surveys Pesquisa Nacional por Amostra de Domicílios (PNAD) 2003, PNAD 2008 and Pesquisa Nacional de Saúde (PNS) 2013. Participants between 18-45 years old were included. Trend analysis of asthma diagnosed prevalence was conducted using a logistic general linear model. A hierarchical logistic regression model was used to select factors significantly associated with asthma prevalence. RESULTS: Asthma diagnosed prevalence was 3.6% (2003), 3.7% (2008) and 4.5% (2013), showing a statistically significant increased trend. Asthma diagnosed prevalence also increased when analysed by gender (annual change for men 2.47%, p < 0.003; women 2.16%, p < 0.001), urban area (annual change for urban 2.15%, p < 0.001; rural 2.69%, p = 0.072), healthcare insurance status (annual change without healthcare insurance 2.18%, p < 0.001; with healthcare insurance 1.84%, p = 0.014), and geographic regions (annual change North 4.68%, p < 0.001; Northeast 4.14%, p < 0.001; and Southeast 1.84%, p = 0.025). Female gender, obesity, living in urban areas and depression were associated with asthma diagnosed prevalence. DISCUSSION: PNAD and PNS surveys allow for a very large, representative community-based sample of the Brazilian adults to investigate the asthma prevalence. From 2003 to 2013, the prevalence of self-reported physician diagnosis of asthma increased, especially in the North and Northeast regions. Gender, region of residence, household location (urban/rural), obesity, and depression diagnosis seem to play significant roles in the epidemiology of asthma in Brazil.