It does not change pulmonary function, which is a major parameter by which physicians quantify severity of illness and disability. Finally, reimbursement for pulmonary rehabilitation services has been inconsistent and often inadequate. If pulmonary rehabilitation were a drug, it would be hard to swallow, with uncertainty about the best dose, route, and frequency of administration, poor taste, complicated directions, no industry support or marketing, temporary effects, and it would be expensive both for the patient and physician. Nevertheless, the scientific foundation and objective and subjective benefits of pulmonary rehabilitation have been soundly established over the past five years. Detailed position papers and evidence-based reviews have been published by the American College of Chest Physicians, The American Thoracic Society, and American Association of Cardiovascular and Pulmonary Rehabilitation.
Programs are now widely available, and the reimbursement support is stabilizing.
Much of the scientific foundation for pulmonary rehabilitation came from study of patients with COPD, the largest group of enrollees. Physiologic improvement has been shown in terms of muscle function and aerobic capacity and cardiac function. These changes have been demonstrated in patients with both moderate impairment and severe impairment previously thought too ill to exercise. The evidence is strongest for the benefits of exercise training. Even there, the optimal intensity, form, and duration are not clear.