RSV and exposure to cigarette smoking as risk factors for severe bronchiolitis in a tropical country

Abstract

Objetive: This study aims to identify risk factors associated with severe bronchiolitis in children. In a retrospective cohort study, we included all infants younger than two years of age in tertiary centers in Rionegro, Colombia, hospitalized due to bronchiolitis from January 2019 to December 2019. Severe bronchiolitis was defined as rhinorrhea, cough, tachypnea, wheezing, rales, and increased respiratory effort (e.g., grunting, nasal flaring, and intercostal and/or subcostal retraction), with symptoms of severity (e.g., increased respiratory rate, retractions, and oxygen saturation at 90% or lower). To identify factors independently associated with severe bronchiolitis, we used log-binomial regression and estimate prevalences ratio (PR) and adjust for potential confounding variables Results: Of a total of 417 included, 300 (72.12%) have severe bronchiolitis. After modeling and controlling for potential confounders in the multivariate analysis: RSV isolation (PR 1.15 95%CI 1.03–1.29) and current exposure to cigarette smoking (PR 1.19 95%CI 1.04–1.35) were independent predictors of severe bronchiolitis. We concluded that RSV and exposure to cigarette smoking are independent predictors of severe bronchiolitis. These potentially modifiable variables associated with severity should guide future interventions to reduce the morbidity and economic burden of bronchiolitis in our population.