Effect of steroid therapy on exercise performance in patients with irreversible chronic obstructive pulmonary disease.

Many patients with irreversible chronic obstructive pulmonary disease (COPD) claim symptomatic improvement with steroid therapy, despite a lack of objective improvement in their spirometric data. To determine if steroids actually increase the exercise capacity of these individuals, 13 clinically stable patients (mean age, 63 +/- 4 years; 12 male patients) were given methylprednisolone (32 mg once daily) or placebo in a randomized double-blind crossover fashion. Spirometric data and minute ventilation, oxygen consumption (VO2), carbon dioxide production, and heart rate during incremental exercise were measured at each visit. Methylprednisolone did not produce a significant change in any of the measured parameters. Three patients had an increase in maximal VO2 of greater than 2 ml/kg/min during therapy with methylprednisolone, while two experienced a decline in maximal VO2 of similar magnitude. The change in exercise capacity was unrelated to the change in the forced expiratory volume in one second in individual patients (r = 0.08). We conclude that in the absence of any improvement in the usual tests of airway mechanics, steroid therapy does not improve exercise performance in patients with COPD.