Airflow limitation during respiratory syncytial virus lower respiratory tract infection predicts recurrent wheezing

Background. Respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) is frequently followed by recurrent wheezing. Thus far no clinical risk factors have been identified to predict which infants will have wheezing episodes subsequent to RSV LRTI. Objective. To determine clinical predictors for airway morbidity after RSV LRTI. Methods. In a 1-year follow-up study we investigated the predictive value of auscultatory findings characteristic of airflow limitation (wheezing) during RSV LRTI for subsequent airway morbidity. Clinical characteristics, including the presence or absence of signs of airflow limitation, of hospitalized infants with RSV LRTI were prospectively recorded during 2 winter epidemics. During a 1-year follow-up period parents of 130 infants recorded daily airway symptoms. Outcome measure. Recurrent wheezing defined as greater than or equal to2 episodes of wheezing. Results. Signs of airflow limitation during RSV LRTI were absent in 47 (36%) infants and present in 83 (64%) infants. Recurrent wheezing was recorded in 10 (21%) infants without signs of airflow limitation and in 51 (61%) with signs of airflow limitation during initial RSV LRTI (relative risk, 0.29, P < 0.001). In a multiple logistic regression model, airflow limitation during initial RSV LRTI proved independent from other clinical parameters, including age, parental history of asthma and smoke exposure. Conclusions. A sign of airflow limitation during RSV LRTI is the first useful clinical predictor for subsequent recurrent wheezing.