Objective: Weight loss and muscle wasting adversely affect morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). Maintenance systemic glucocorticosteroids, prescribed in a substantial number of patients, further contribute to muscle weakness. We investigated the efficacy of oral nutritional supplementation therapy in depleted patients with COPD.
Methods: The therapy consisted of daily two to three oral liquid nutritional supplements (mean +/- standard deviation: 2812 +/- 523 kJ/24 h) incorporated into an 8-wk inpatient pulmonary rehabilitation program in 64 (49 men) depleted patients with COPD. Endpoints were body weight, fat-free mass by bioelectrical impedance analysis, respiratory and peripheral muscle function (maximal inspiratory mouth pressure and handgrip strength, respectively), exercise performance (incremental bicycle ergometry), and disease-specific health status by St. George's Respiratory Questionnaire. Forty-eight percent of the patients were treated with low-dose oral glucocorticosteroids as maintenance medication (dose equivalent to 7.6 +/- 2.5 mg of methylprednisolone per day).
Results: Increases in body weight (2.1 +/- 2.1 kg, P < 0.001) and fat-free mass (1.1 +/- 2.0 kg, P < 0.001) were seen. Further, maximal inspiratory mouth pressure (4 +/- 10 cm of H(2)O, P = 0.001), handgrip strength (1.2 +/- 3.1 kg, P = 0.004), and peak workload (7 +/- 11 W, P = 0.001) significantly improved. Clinically significant improvements in the items symptoms (9 +/- 16 points, P < 0.001) and impact (4 +/- 15 points, P = 0.043) of St. George's Respiratory Questionnaire were achieved. Oral glucocorticosteroid treatment significantly impaired the response to nutritional supplementation therapy with respect to maximal inspiratory mouth pressure, peak workload, and St. George's Respiratory Questionnaire symptom score.
Conclusions: Nutritional supplementation therapy implemented in a pulmonary rehabilitation program was effective in depleted patients with COPD. However, oral glucocorticosteroid treatment attenuated the anabolic response to nutritional supplementation.