Publication:

Epidemiology of wheezing in infants in the region of Pamplona

Background: wheezing in the first year of life affect both infant and parental quality of life. Risk factors as male gender, nursery attendance, presence of damp or mould stains at home, or family history of asthma and allergies, and protective factors such as breastfeeding more than six months have been previously described. The aim of this study was to investigate the prevalence and risk and protective factors for wheeze ever, recurrent wheeze and severe wheeze in infants in the region of Pamplona, Spain. Material and methods: this cross-sectional study was part of the International Study of Wheezing in Infants (in Spanish, Estudio Internacional de Sibilancias en Lactantes, or EISL). Between 2006 and 2008, participating families answered a standardised validated questionnaire on demographic and anthropometric factors, respiratory and allergy symptoms, family background, environmental factors, and exposures during pregnancy and birth. Bivariate analyses (using chi-squared test or Student’s t-test, as appropriate) were conducted, calculating odds ratios with 95% confidence intervals. Also, multivariate models were used to adjust for confounding variables. A p value lower than 0.05 was regarded as statistically significant. Results: 1,065 questionnaires were answered. Prevalence of wheeze ever was 32.5%. Prevalences of recurrent and severe wheeze were 10.6% and 9.6%, respectively. Male gender, pneumonia in the first year of life, infant eczema, higher number of colds, prenatal exposure to tobacco smoke, nursery attendance and presence of pets in the household were some of the risk factors identified. Conversely, a longer exclusive breastfeeding was found as protective factor. Conclusions: wheezing in infants is an important public health issue, that can lead to asthma in childhood. Prevalences found in this study were comparable to others found in European centres, but lower than those found in Latin American countries. Several preventable risk factors have been identified.