Prevalence of wheezing in the chest among adults from the 1982 Pelotas birth cohort, Southern Brazil

OBJECTIVE: To estimate the prevalence of wheezing in the chest among adults, and to explore the effect of some variables on the prevalence of this condition. METHODS: This was a prospective cohort study on individuals born in the city of Pelotas (Southern Brazil) in 1982. A total of 4,297 subjects was traced in 2004-5, representing 77.4% of the original cohort. Data were collected by means of interviews using the ISAAC (International Study of Asthma and Allergies in Childhood Steering Committee) questionnaire. Associations between the outcome "occurrence of wheezing in the chest within the 12 months prior to the interview" and the variables of socioeconomic, demographic and birth characteristics were tested by means of multivariable analyses, using Poisson regression. RESULTS: The prevalence of wheezing over the preceding year was 24.9%. Among the individuals reporting wheezing, 54.6% reported difficulty in sleeping, and 12.9% reported difficulty in speaking due to wheezing. The prevalence of wheezing in the chest was significantly higher among women. This association was maintained in analyses adjusted for non-white skin color, family history of asthma and low socioeconomic level. Among men, there was no significant association in the analyses adjusted for skin color and family income at birth. Family histories of asthma and poverty throughout life presented significant associations with wheezing in the chest. For both sexes, there were no associations with the variables of birth weight and breastfeeding duration. CONCLUSIONS: The prevalence of wheezing in the chest was high, and subjects with low family income at birth were more likely to have had wheezing in the chest over the preceding year.