Published studies provide a sound scientific basis for the overall intervention, as well as its specific components (albeit at a lower level of evidence).
After rehabilitation, patients report improvement in HRQoL, a reduction in respiratory symptoms, increases in exercise tolerance and their ability to perform ADL, and greater independence. However, pulmonary rehabilitation has no effect on lung function or gas exchange (table 1).
Most COPD patients benefit from a pulmonary rehabilitation programme. Although some reports suggest that one-quarter to one-third of patients show no response, studies have failed to identify important predictors of treatment success or failure.
Studies (mostly uncontrolled) evaluating the costs of pulmonary rehabilitation have reported a positive cost/benefit ratio, mostly due to a reduction in hospitalisation frequency after rehabilitation. A recent health economic analysis performed by the London School of Economics, the British Thoracic Society (BTS) and the Primary Care Respiratory Society UK (PCRS-UK) suggested that pulmonary rehabilitation is one of the most cost-effective treatments available. In fact, its cost per quality-adjusted life-year (QALY) is less than that of most long-term inhaled therapy.
A large, prospective, controlled trial would be necessary to examine the possible effect of pulmonary rehabilitation on mortality, but given that a great deal of evidence already exists showing its health benefits, such a trial would be impossible to carry out as it would be considered unethical to deny rehabilitation to a control group. The effect of pulmonary rehabilitation on survival is therefore likely to remain unquantified. Nevertheless, as COPD patients with better exercise tolerance, less breathlessness and lower rates of hospitalisation have higher survival rates and pulmonary rehabilitation provides these benefits, it is reasonable to assume that it is likely to result in a survival advantage.
|Outcome||Evidence for expected improvements|
|Health-related quality of life||+++|
|Health resource consumption||++|
|Respiratory muscle function||++|