Comparison of intramuscular triamcinolone and oral prednisone in the outpatient treatment of acute asthma: a randomized controlled trial

Abstract

Study objective: To determine whether a one-time dose of triamcinolone diacetate, 40 mg intramuscular (i.m.), given to adult patients treated in the emergency department for mild to moderate exacerbation of asthma would decrease the rate of relapse during the following week, compared with a nontapering course of oral prednisone, 40 mg/day over 5 days.

Methods: A randomized, double-blind, controlled clinical trial was conducted at two university-affiliated community teaching hospitals with a combined annual census of 97,000. Patients were eligible if they were between the ages of 18 and 50 years, had an initial peak expiratory flow rate of less than 350 L/minute, and were to be discharged from the ED taking steroids. Patients were randomly assigned to receive either triamcinolone (40 mg i.m.) and placebo tablets or a placebo injection and prednisone (40 mg/day orally for 5 days). Patients were instructed to use a beta-agonist metered-dose inhaler, to continue other routine medications, to complete symptom diary cards, and to return in 7 to 10 days for follow-up. The main outcome measure was relapse, which was defined as an unscheduled visit to a physician's office or ED for worsening or persistent symptoms within 7 days of the initial ED visit.

Results: A total of 168 patients were initially enrolled; 6 patients were withdrawn for protocol violations and 8 because they could not be contacted for follow-up. A total of 154 patients were available for outcome analysis, 78 in the triamcinolone group and 76 in the prednisone group. There were no differences between the two patient groups with regard to demographics, smoking history, weight, or symptom severity. Mean initial peak flows were 244+/-64 L/minute for the triamcinolone group and 245+/-83 L/minute for the prednisone group. Fifty percent of the study patients were current smokers. The relapse rates were 9.0% (7/78) in the triamcinolone group and 14.5% (11/76) in the prednisone group (P=.29). The absolute difference in relapse rates was 5.5% (95% confidence interval [CI], 4.6% to 15.6%). There was no difference in symptom frequency or severity between the two groups during the first 5 days of outpatient treatment. Analysis between the groups stratified for smoking showed no difference in relapse rate between smokers and nonsmokers.

Conclusion: A single dose of triamcinolone diacetate, 40 mg i.m., produced a relapse rate similar to that of prednisone, 40 mg/day orally for 5 days, after ED treatment of mild to moderate exacerbations of asthma. Intramuscular triamcinolone would appear to be an attractive alternative when compliance with a daily oral regimen is of concern.