51 Prevalence of Wheezing and Risk Factors Associated to Wheezing in Infants in the First Year of Life, Cuibá, MT, Brazil

BACKGROUND: The purpose of this study was to evaluate the prevalence of wheezing and risk factors related to wheezing in infants (12–15 month-old) in the city of Cuiabá, Mato Grosso State, Brazil. METHODS: Cross-sectional study by applying a standardized written questionnaire from “Estudio Internacional de sibilancia en lactentes” (EISL) phase III. Parents and/or guardians of infants were interviewed at a primary health care clinic or at home from August 2009 to November 2010. Signed written informe consent was obtained from parents and/or guardians of all subjects. Factors associated to wheezing were studied using bivariate and multivariate analysis (SPSS v.18.0) and expressed as odds ratio (OR) and confidence interval 95% (95% CI). RESULTS: One thousand sixty parents were interviewed (N = 1060), 27.7% (N = 294) infants had at least one wheezing episode in their first year of life, with onset at 5.8 ± 3.0 months (mean ± standard deviation), and 45.9% (N = 135) had had 3 or more episodes (recurrent wheezing). The use of inhaled β2-agonists, oral corticosteroids or leukotriene receptor antagonist, nocturnal symptoms, respiratory distress, hospitalization and medical diagnose of asthma were significantly more frequent in the group with recurrent wheezing (P < 0.05). Independent risk factors associated with wheezing in the first year of life were: history of previous pneumonia (OR = 10.80; 95% CI, 4.52-25.77); to have more than 6 upper respiratory infections (URI) (OR = 2.95; 95% CI, 2.11-4.14); asthma in sibling (OR = 2.13; 95% CI, 1.18-3.87); asthma in father (OR = 1.98; 95% CI, 1.22-3.23); asthma in mother (OR = 1.62; 95% CI, 1.07-2.43); exposure to paracetamol in the first year of life for URI (OR = 2.13; 95% CI, 1.54-2.95); exposure to moderate air pollution from traffic (OR = 1.59; 95% CI, 1.08-2.33); and a first URI before of third month of age (OR = 1.50; 95% CI, 1.04-2.17). CONCLUSIONS: The prevalence of wheezing episodes among one year-old infants living in Cuiabá was high and early in life. Risk factors for wheezing are similar to risk factors for asthma. Exposure to paracetamol was associated with wheezing but more researches are required to clarify this potential association.