Severe bronchiolitis in infancy: can asthma in adolescence be predicted?

Bronchiolitis in infancy is a risk factor for development of asthma in the first decades of life, although the majority may be asymptomatic at school age. Respiratory symptoms are common in early life, and prediction of later asthma may be challenging. We aimed to study if simple clinical variables assessed at 2 years of age could predict asthma at 11 years of age and thereby provide a basis for follow-up and treatment after bronchiolitis in infancy. The study included 105 children hospitalized for bronchiolitis during their first year of life. Of these, 101 (96.2%) participated in the first follow-up at 2 years of age and 93 (88.6%) in the second follow-up at age 11. The overall prevalence of asthma at 11 years of age was 22.6%. Among the risk factors assessed at 2 years of age, recurrent wheeze appeared most important (odds ratio for later asthma: 7.2; 95% confidence interval: 1.3, 41.6; P = 0.015). Tested separately, recurrent wheeze had high sensitivity (90.5%), but low specificity (58.3%), low negative likelihood ratio (LR) (0.2) and low negative post-test probability (4.5%); indicating that absence of recurrent wheeze was better suited to exclude than to predict asthma at 11 years of age. Combining recurrent wheeze with either parental atopy, parental asthma or atopic dermatitis improved the specificity (>80), positive LR (>3) and positive post-test probability (∼50%), rendering the combinations more appropriate for the prediction of later asthma. In conclusion, after bronchiolitis in infancy, simple clinical non-invasive variables assessed at 2 years of age could predict asthma at 11 years of age with reasonable accuracy. However, the data were better suited to exclude than to predict later asthma.