Prevalence and clinical characteristics of wheezing in children in the first year of life, living in Cuiabá, Mato Grosso, Brazil☆

OBJECTIVE To evaluate the prevalence and the clinical characteristics of wheezing in 12-15 months old infants in the city of Cuiabá, Mato Grosso State, Midwest Brazil. METHODS Parents and/or guardians of infants were interviewed and completed a written standardized questionnaire of the "Estudio Internacional de Sibilancia en Lactantes" (EISL) - phase 3 at primary health care clinics at the same day of children vaccination or at home, from August 2009 to November 2010. RESULTS 1,060 parents and/or guardians completed the questionnaire, and 514 (48.5%) infants were male. Among the studied infants, 294 (27.7%) had at least one episode of wheezing during the first year of life, beginning at 5.8±3.0 months of age, with a predominance of male patients. The prevalence of occasional wheezing (<3 episodes of wheezing) was 15.0% and recurrent wheezing (≥ 3 episodes) was 12.7%. Among the infants with recurrent wheezing, the use of inhaled β2-agonist, oral corticosteroid, leukotriene receptor antagonist, as well as night symptoms, respiratory distress and hospitalization due to severe episodes were significantly more frequent. Physician-diagnosed asthma was observed in 28 (9.5%) of the wheezing infants. Among the wheezing infants, 80 (27.7%) were diagnosed with pneumonia, of whom 33 (11.2%) required hospitalization, neverthless no differences between occasional and recurrent wheezing infants were found. CONCLUSIONS The prevalence of recurrent wheezing and physician-diagnosed asthma in infants were lower compared with those found in other Brazilian studies Recurrent wheezing had early onset and high morbity.