Serious childhood respiratory infections and asthma in adult life. A population based study. ECRHS Italy. European Community Respiratory Health Survey.

Abstract

A number of epidemiologic studies have tried to establish whether respiratory tract infections in early childhood cause obstructive pulmonary disease in adult life. To determine whether reported serious respiratory infection before the age of 5 years (SRI) is a significant risk factor for subsequent development of bronchial asthma and/or bronchial hyperresponsiveness in adults. We investigated a random population sample of 1,104 subjects (aged 20 to 40 years), participating in the European Respiratory Health Survey in Italy. Bronchial response to methacholine and answers to a standardized questionnaire were analyzed. The prevalence of SRI (ie, a positive response to the question "Have you ever had a serious respiratory infection before the age of 5 years?") was significantly higher in the subjects with a positive family history of allergic diseases than in those with a negative one (O.R. 1.89; 95% C.I. 1.24 to 2.87, P < .01). No relationship was found between SRI and current adult asthma; however, asthma in the past was found in 20.5% of the SRI positive subjects and in 9.1% of SRI negative subjects (O.R. 2.47; 95% C.I. 1.47 to 4.15, P < .05). No difference in the response to methacholine and in FEV1, FEV1/FVC values was found between SRI positive and SRI negative subjects. We suggest that a positive family history of atopy is associated with a significantly higher prevalence of SRI. Furthermore our results indicate that exposure to SRI is a risk factor for asthma in the past (ie, asthma in childhood and adolescence) but not for adult asthma or for the development of bronchial impairment in adult life.