<LEAP> highlights the findings and application of Cochrane reviews and other evidence pertinent to the practice of physical therapy. The Cochrane Library is a respected source of reliable evidence related to health care. Cochrane systematic reviews explore the evidence for and against the effectiveness and appropriateness of interventions—medications, surgery, education, nutrition, exercise—and the evidence for and against the use of diagnostic tests for specific conditions. Cochrane reviews are designed to facilitate the decisions of clinicians, patients, and others in health care by providing a careful review and interpretation of research studies published in the scientific literature.1 Each article in this new PTJ series will summarize a Cochrane review or other scientific evidence resource on a single topic and will present clinical scenarios based on real patients to illustrate how the results of the review can be used to directly inform clinical decisions. The first article in the series focuses on a patient with chronic obstructive pulmonary disease (COPD) who has had a recent exacerbation that required medical intervention. Should this patient undergo pulmonary rehabilitation?
The American Thoracic Society defines COPD as “a preventable and treatable disease state characterized by airflow limitation that is not fully reversible. The airflow limitation is usually progressive and is associated with an abnormal inflammatory response of the lungs to noxious particles or gases, primarily caused by cigarette smoking. Although COPD affects the lungs, it also produces significant systemic consequences.”2 Prevalence of COPD in adults who are 40 years old or older is approximately 10%.3 Chronic obstructive pulmonary disease is a leading cause of death and disability,4 and acute exacerbation is one of the main causes of hospitalization and death.5 An exacerbation of COPD is defined as “an event in the natural course of the disease characterized by a change in the patient's baseline dyspnea, cough, and/or sputum, that is beyond normal day-to-day variations, is acute in onset and may warrant a change in medication in a patient with underlying COPD.”6(p xiv)
Pulmonary rehabilitation has been shown to be effective in improving exercise capacity, physical function, and quality of life and in reducing dyspnea and fatigue in people with COPD.7 Pulmonary rehabilitation takes many forms but usually includes, at a minimum, exercise training and patient education. Other interventions may include smoking cessation strategies, ventilatory muscle training, airway clearance techniques, medication management, and psychological support. Because the studies included in a 2006 Cochrane systematic review only had participants without recent COPD exacerbations,7 Puhan et al8 conducted an additional Cochrane review of randomized clinical trials to determine the effect of pulmonary rehabilitation on patients with recent COPD exacerbations requiring inpatient or outpatient care. In the review, the pulmonary rehabilitation intervention had to include at least some form of exercise training beginning within 3 weeks of the COPD exacerbation. The primary outcome of interest was subsequent hospital admissions. Secondary outcomes also were examined, such as mortality, quality of life, and exercise capacity. The results of the review are outlined in the Table.
Pulmonary Rehabilitation for Chronic Obstructive Pulmonary Disease (COPD): Cochrane Review Results8
Take-Home Message
The Cochrane review by Puhan et al8 indicates that pulmonary rehabilitation is effective in reducing the chance of hospitalization and mortality following an acute exacerbation of COPD. Pulmonary rehabilitation following acute COPD exacerbation also results in improvements in health-related quality of life and exercise capacity. Adverse effects of pulmonary rehabilitation following an acute exacerbation of COPD were not found in the review.
Because pulmonary rehabilitation programs commonly focus on educating the patient to make such lifestyle changes as increasing physical activity, reducing smoking, and seeking care for early signs of upper respiratory infections, an advantage of pulmonary rehabilitation following acute exacerbation of COPD may be related to patients’ improved readiness to change following the distress of an acute episode. In addition, patients who participate in a pulmonary rehabilitation program have continuity of care in terms of reinforcing proper use of medication and attention to important symptoms. A potential disadvantage of participating in a pulmonary rehabilitation program following an acute exacerbation of COPD is that patients may have severely reduced endurance, necessitating a slower progression of exercise and a longer rehabilitation process to gain clinically important improvements. An understanding of the relative benefits and limitations of pulmonary rehabilitation after an acute exacerbation of COPD is useful when making clinical decisions with individual patients.
<LEAP> Case #1: Applying Evidence to a Patient With COPD
Can pulmonary rehabilitation help this patient?
Ms Wilson is a 64-year-old woman with a 10-year history of COPD who had a series of 3 COPD exacerbations over a 4-month period. These exacerbations required medical intervention with antibiotic treatment and oral steroids, but she was never hospitalized. Following the third exacerbation, Ms Wilson complained of moderate exertional dyspnea and was unable to perform her usual exercise program at home. Her forced expiratory volume in 1 second (FEV1) was 35% of predicted level. Ms Wilson's impairments included reduced exercise capacity with a 6-minute walk distance of 385 m (predicted=497 m17), impaired ventilation with an inability to properly pace breathing during activity, reduced lower-extremity muscle strength, and impaired gas exchange with desaturation to 86% on 3 L/min of supplemental oxygen during activity. Completion of the Chronic Respiratory Disease Questionnaire (CRQ) yielded the following scores: dyspnea=13/35, fatigue=18/28, emotional function=35/49, and mastery=17/28. Ms Wilson's goals were to improve activity tolerance, avoid further COPD exacerbations, maintain oxygen saturation above 90%, and return to work.
How did the results of the Cochrane systematic review apply to Ms Wilson?
Based on evidence from the systematic review described in this article, Ms Wilson, her physician, and her physical therapist agreed that she would be a good candidate for an outpatient pulmonary rehabilitation program. Ms Wilson began an outpatient pulmonary rehabilitation consisting of 2-hour supervised group sessions twice per week. The program included endurance training and strengthening and flexibility exercises over an 18-week period. Stair climbing with instruction in paced breathing strategies was incorporated gradually. Ms Wilson completed all exercises with 3 L/min of supplemental oxygen.
How well do the outcomes of the intervention provided to Ms Wilson match those suggested by the systematic review?
By the end of the 18-week period, 6-minute walk distance had increased to 442 m. The CRQ score improvements included: dyspnea=20/35, fatigue=20/28, emotional function=38/49, and mastery=22/28. In addition, all muscle groups demonstrated strength improvements. Ms Wilson met her goals of returning to part-time work and restarting her home walking program. She had no hospitalizations.
Can you apply the results of the systematic review to your own patients?
The findings of this review apply well to patients with acute exacerbations of COPD. The review criteria allowed studies with patients requiring inpatient or outpatient care; however, the review found only studies in which participants had been hospitalized for their exacerbations, and Ms Wilson had not been hospitalized to manage her exacerbations. The health care team still considered that it was reasonable to extrapolate the findings from the review to Ms Wilson's case. She was otherwise similar to trial participants, and there were no compelling reasons to expect that the results would not be generalizable to patients who have exacerbations managed out of the hospital.
What can be advised based on the results of this systematic review?
Patients fitting the description of the participants as outlined in the Table are likely to benefit from an inpatient, outpatient, or home-based pulmonary rehabilitation program that includes endurance exercise training, strengthening exercises, and education. Similar to participants in the included studies and Ms Wilson, people engaging in a pulmonary rehabilitation program following acute exacerbation are likely to show clinically meaningful improvements in health-related quality of life and exercise capacity. Finally, patients engaging in pulmonary rehabilitation may reduce their chances for future hospitalizations and odds of death over a period of 3 months to 4 years.
- © 2010 American Physical Therapy Association