Article type
Year
Abstract
Introduction:
Objectives: To determine, in asthmatic patients, the effectiveness of the addition of long-acting p2-agonists to inhaled corticosteroids on the incidence of asthma exacerbations, pulmonary function and other measure of asthma control.
Methods: We identified randomized controlled trials (RCTs) through electronic database searches, bibliographies of RCTs, correspondence with the manufacturers, and personal contact with trialists. RCTs examining the addition of inhaled long-acting p2-agonists to corticosteroids with corticosteroids alone, in children aged 2 years and above and adults with asthma, were included. Confirmation of methodology and data was obtained from authors when possible. The primary endpoint was rate of asthma exacerbations requiring oral corticosteroids. Secondary endpoints included pulmonary function tests (PFTs), adverse events and withdrawal rates.
Results: Of 724 citations identified, 25 trials were considered relevant and were reviewed in full text Of these, 9 trials fit the inclusion criteria and most (N=5) were of high quality. Trials were stratified on the daily dose of inhaled corticosteroids (S1000 ug, <1000 ug, or variable doses of beclomethasone-equivalent). The addition of a daily long-acting p2-agonists to inhaled corticosteroids reduced the risk of asthma exacerbations requiring oral corticosteroids by 12% [N=6 trials, RR=0.88 (95% CI: 0.78,0.99)]. Although there was no statistical heterogeneity between strata, the protective effect of long-acting p2-agonists was only observed in patients treated with <1000 ug daily doses [N=2 trials, RR=0.84 (95% CI: 0.73,0.93)] or variable doses of inhaled steroids [N=3 trials, RR=0.86 (95% CI: 0.68, 1.09)]. The change from baseline in morning peak flow at 10 +- 2 weeks was significantly greater in the group receiving inhaled long-acting p2-agonists and steroids than the group receiving steroids alone [N=2 trials, WMD=16.5 (95% CI: 5.8,27.2) L/min]. The overall withdrawal rate was similar in the both groups [N=4 trials, RR=1.12 (95% CI: 0.78, 1.60)].
Discussion: The addition of inhaled long-acting p2-agonists to corticosteroids improves lung function and reducing the rate of asthma exacerbations requiring oral corticosteroids by 12%. The similar withdrawal rate provides some indirect evidence of the safety of long-acting p2-agonists.
Objectives: To determine, in asthmatic patients, the effectiveness of the addition of long-acting p2-agonists to inhaled corticosteroids on the incidence of asthma exacerbations, pulmonary function and other measure of asthma control.
Methods: We identified randomized controlled trials (RCTs) through electronic database searches, bibliographies of RCTs, correspondence with the manufacturers, and personal contact with trialists. RCTs examining the addition of inhaled long-acting p2-agonists to corticosteroids with corticosteroids alone, in children aged 2 years and above and adults with asthma, were included. Confirmation of methodology and data was obtained from authors when possible. The primary endpoint was rate of asthma exacerbations requiring oral corticosteroids. Secondary endpoints included pulmonary function tests (PFTs), adverse events and withdrawal rates.
Results: Of 724 citations identified, 25 trials were considered relevant and were reviewed in full text Of these, 9 trials fit the inclusion criteria and most (N=5) were of high quality. Trials were stratified on the daily dose of inhaled corticosteroids (S1000 ug, <1000 ug, or variable doses of beclomethasone-equivalent). The addition of a daily long-acting p2-agonists to inhaled corticosteroids reduced the risk of asthma exacerbations requiring oral corticosteroids by 12% [N=6 trials, RR=0.88 (95% CI: 0.78,0.99)]. Although there was no statistical heterogeneity between strata, the protective effect of long-acting p2-agonists was only observed in patients treated with <1000 ug daily doses [N=2 trials, RR=0.84 (95% CI: 0.73,0.93)] or variable doses of inhaled steroids [N=3 trials, RR=0.86 (95% CI: 0.68, 1.09)]. The change from baseline in morning peak flow at 10 +- 2 weeks was significantly greater in the group receiving inhaled long-acting p2-agonists and steroids than the group receiving steroids alone [N=2 trials, WMD=16.5 (95% CI: 5.8,27.2) L/min]. The overall withdrawal rate was similar in the both groups [N=4 trials, RR=1.12 (95% CI: 0.78, 1.60)].
Discussion: The addition of inhaled long-acting p2-agonists to corticosteroids improves lung function and reducing the rate of asthma exacerbations requiring oral corticosteroids by 12%. The similar withdrawal rate provides some indirect evidence of the safety of long-acting p2-agonists.