Effect of long-acting beta2 agonists on exacerbation rates of asthma in children.

The purpose of this analysis was to examine the effect of long-acting beta(2)-adrenoceptor agonists (LABAs) on the asthma exacerbation rate in pediatric patients. Randomized controlled trials (RCT) that included the use of LABAs to treat symptoms of pediatric asthma in children on inhaled corticosteroids, that reported asthma exacerbation rates, and that were published as full papers in peer-reviewed journals were retrieved from a search of the medical literature. Eight studies were identified that fulfilled these criteria. An exacerbation was defined as deterioration in a patient's asthma requiring a change in prescribed medication or not defined but reported as an asthma exacerbation or an asthma-related hospitalization. Analysis of data from the eight studies revealed no apparent protection from an asthma exacerbation among children on a LABA compared to patients on comparator treatment. The relative risk of an asthma exacerbation for LABA compared to placebo or short-acting beta(2)-adrenoceptor agonist (SABA) ranged from 0.95-1.86. The relative risk of hospitalization for asthma in patients treated with LABAs with regular maintenance with ICS ranged from 3.3-21.6 in the three studies that reported asthma-related hospitalizations. The lack of evidence for the control of asthma exacerbations in children regularly using a LABA should bring into question its general use as add-on therapy. Studies should be designed to directly explore the implications of these observations in pediatric patients.