Efficacy of inhaled corticosteroids in infants and preschoolers with recurrent wheezing and asthma: a systematic review with meta-analysis.

OBJECTIVE To compare the efficacy of inhaled corticosteroids in infants and preschoolers with recurrent wheezing or asthma. METHODS Randomized, prospective, controlled trials published January 1996 to March 2008 with a minimum of 4 weeks of inhaled corticosteroids versus placebo were retrieved through Medline, Embase, and Central databases. The primary outcome was wheezing/asthma exacerbations; secondary outcomes were withdrawal caused by wheezing/asthma exacerbations, changes in symptoms score, pulmonary function (peak expiratory flow and forced expiratory volume in 1 second), or albuterol use. RESULTS Of eighty-nine studies identified, 29 (N = 3592 subjects) met the criteria for inclusion. Patients who received inhaled corticosteroids had significantly less wheezing/asthma exacerbations than those on placebo (18.0% vs 32.1%); posthoc subgroup analysis suggests that this effect was higher in those with a diagnosis of asthma than wheeze but was independent of age (infants versus preschoolers), atopic condition, type of inhaled corticosteroid (budesonide metered-dose inhaler versus fluticasone metered-dose inhaler), mode of delivery (metered-dose inhaler versus nebulizer), and study quality (Jadad score: <4 vs >/=4) and duration (<12 vs >/=12 weeks). In addition, children treated with inhaled corticosteroids had significantly fewer withdrawals caused by wheezing/asthma exacerbations, less albuterol use, and more clinical and functional improvement than those on placebo. CONCLUSIONS Infants and preschoolers with recurrent wheezing or asthma had less wheezing/asthma exacerbations and improve their symptoms and lung function during treatment with inhaled corticosteroids.