Effects of montelukast and salmeterol on physical performance and exercise economy in adult asthmatics with exercise-induced bronchoconstriction.

STUDY OBJECTIVES: To compare the effect of montelukast and the long-acting beta(2)-agonist salmeterol on cardiopulmonary exercise economy and physical performance in adult patients with asthma during exercise.

DESIGN AND PATIENTS: Asthmatic patients (n = 18), aged 18 to 35 years with exercise-induced bronchoconstriction (EIB), using a double-blind, double-dummy cross-over design. Montelukast, 10 mg/d, was compared to inhaled salmeterol, 50 microg bid. The study medication was administered for at least 5 days prior to testing, with a washout period of at least 5 days. Treadmill exercise tests (5.3% inclination, -15 degrees C ambient temperature) were performed at work loads of 80% of maximal oxygen uptake (Vo(2)max) [6 min], rest (4 min), 60% of Vo(2)max (6 min), and finally step increments until exhaustion.

MEASUREMENTS AND RESULTS: We investigated parameters of gas exchange, physical performance, and lung function. After montelukast, the oxygen pulse was higher than after salmeterol, at 80% of Vo(2)max (p = 0.035), and 6 min at 60% of Vo(2)max (p = 0.011). Lung function during exercise, running time to exhaustion, Borg score, lactate levels, Vo(2)max, carbon dioxide elimination, minute ventilation, ventilatory equivalents, respiratory exchange ratio, and heart rate were not significantly different between the two treatments. The maximal postexercise fall in FEV(1) from baseline occurred 2 min after run to exhaustion, and was greater after salmeterol than after montelukast: mean, 16.2% (SD, 11.0) vs 10.0% (SD, 12.2) [p < 0.001].

CONCLUSIONS: In adult asthmatics with EIB, montelukast may have a more favorable effect on the oxygen pulse, thus suggesting improved gas exchange during exercise.