Risk factors for recurrent wheezing in infants: a case-control study

Abstract

OBJECTIVE: To evaluate the association between recurrent wheezing and atopy, the AsthmaPredictive Index, exposure to risk factors, and total serum IgE levels as potential factors to predictrecurrent wheezing.METHODS: A case-control study with infants aged 6-24 months treated at a specializedoutpatient clinic from November 2011 to March 2013. Evaluations included sensitivity to inhalantand food antigens, positive Asthma Predictive Index, and other risk factors for recurrent wheezing(smoking during pregnancy, presence of indoor smoke, viral infections, and total serum IgE levels).RESULTS: We evaluated 113 children: 65 infants with recurrent wheezing (63.0% male) witha mean age of 14.8 (SD = 5.2) months and 48 healthy infants (44.0% male) with a mean age of15.2 (SD = 5.1) months. In the multiple analysis model, antigen sensitivity (OR = 12.45; 95%CI1.28–19.11), positive Asthma Predictive Index (OR = 5.57; 95%CI 2.23–7.96), and exposure toenvironmental smoke (OR = 2.63; 95%CI 1.09–6.30) remained as risk factors for wheezing.Eosinophilia ≥ 4.0% e total IgE ≥ 100 UI/mL were more prevalent in the wheezing group, butfailed to remain in the model. Smoking during pregnancy was identified in a small number ofmothers, and secondhand smoke at home was higher in the control group.CONCLUSIONS: Presence of atopy, positive Asthma Predictive Index and exposure toenvironmental smoke are associated to recurrent wheezing. Identifying these factors enablesthe adoption of preventive measures, especially for children susceptible to persistent wheezingand future asthma onset