Effect of long-term treatment with salmeterol on asthma control: a double blind, randomised crossover study.

Abstract

To determine the effect of adding salmeterol 50 micrograms twice daily for six months to current treatment in subjects with asthma who control their inhaled corticosteroid dose according to a management plan. A double blind, randomised crossover study. Nottingham. 101 subjects with mild or moderate asthma taking at least 200 micrograms twice daily of beclomethasone dipropionate or budesonide. Salmeterol 50 micrograms twice daily and placebo for six months each, with a one month washout. Subjects adjusted inhaled steroid dose according to guidelines. Reduction in inhaled steroid use, exacerbations of asthma, and use of oral steroids. Data were available for 87 subjects. When compared with placebo salmeterol treatment was associated with a 17% reduction in inhaled steroid use (95% confidence interval 12% to 22%) with no significant difference in the number of subjects who had an exacerbation (placebo 25%, salmeterol 16%) or use of oral steroids. For secondary end points salmeterol treatment was associated with higher morning and evening peak expiratory flow and forced expiratory volume in one second; a reduction in symptoms, bronchodilator use and airway responsiveness to methacholine; and no effect on serum potassium concentration, 24 hour heart rate, or the final forced expiratory volume in one second achieved during a salbutamol dose-response study. In subjects who adjusted their inhaled steroid treatment according to guidelines the addition of salmeterol 50 micrograms twice daily was associated with a reduction in inhaled steroid use and improved lung function and symptom control.