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Joint American College of Chest Physicians/American Association of Cardiovascular and Pulmonary Rehabilitation Evidence-Based Clinical Practice Guidelines |

Pulmonary Rehabilitation*: Joint ACCP/AACVPR Evidence-Based Clinical Practice Guidelines FREE TO VIEW

Andrew L. Ries, MD, MPH, FCCP (Chair); Gerene S. Bauldoff, RN, PhD, FCCP; Brian W. Carlin, MD, FCCP; Richard Casaburi, PhD, MD, FCCP; Charles F. Emery, PhD; Donald A. Mahler, MD, FCCP; Barry Make, MD, FCCP; Carolyn L. Rochester, MD; Richard ZuWallack, MD, FCCP; Carla Herrerias, MPH
Author and Funding Information

*From the University of California, San Diego, School of Medicine (Dr. Ries, Chair, representing both groups), San Diego, CA; The Ohio State University College of Nursing (Dr. Bauldoff, representing the AACVPR, and Dr. Emery, representing the AACVPR), Columbus, OH; Allegheny General Hospital (Dr. Carlin, ACCP Health and Science Policy Liaison, representing both groups), Pittsburgh, PA; the Los Angeles Biomedical Research Institute (Dr. Casaburi, representing the ACCP), Harbor-UCLA Medical Center, Los Angeles, CA; the Department of Pulmonary and Critical Care Medicine (Dr. Mahler, representing the ACCP), Dartmouth-Hitchcock Medical Center, Lebanon, NH; the Department of Pulmonary Rehabilitation and Emphysema (Dr. Make, representing the ACCP), National Jewish Research and Medical Center, Denver, CO; the Section of Pulmonary and Critical Care (Dr. Rochester, representing the ACCP), Yale University School of Medicine, New Haven, CT; the Pulmonary Disease Section (Dr. ZuWallack, representing the AACVPR), St. Francis Hospital, Hartford, CT; and the American College of Chest Physicians (Ms. Herrerias), Northbrook, IL.

Correspondence to: Andrew L. Ries, MD, MPH, FCCP, University of California, San Diego, Department of Pulmonary and Critical Care Medicine, UCSD Medical Center, 200 West Arbor Dr, San Diego, CA 92103-8377; e-mail: aries@ucsd.edu


Chest. 2007;131(5_suppl):4S-42S. doi:10.1378/chest.06-2418
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Background: Pulmonary rehabilitation has become a standard of care for patients with chronic lung diseases. This document provides a systematic, evidence-based review of the pulmonary rehabilitation literature that updates the 1997 guidelines published by the American College of Chest Physicians (ACCP) and the American Association of Cardiovascular and Pulmonary Rehabilitation.

Methods: The guideline panel reviewed evidence tables, which were prepared by the ACCP Clinical Research Analyst, that were based on a systematic review of published literature from 1996 to 2004. This guideline updates the previous recommendations and also examines new areas of research relevant to pulmonary rehabilitation. Recommendations were developed by consensus and rated according to the ACCP guideline grading system.

Results: The new evidence strengthens the previous recommendations supporting the benefits of lower and upper extremity exercise training and improvements in dyspnea and health-related quality-of-life outcomes of pulmonary rehabilitation. Additional evidence supports improvements in health-care utilization and psychosocial outcomes. There are few additional data about survival. Some new evidence indicates that longer term rehabilitation, maintenance strategies following rehabilitation, and the incorporation of education and strength training in pulmonary rehabilitation are beneficial. Current evidence does not support the routine use of inspiratory muscle training, anabolic drugs, or nutritional supplementation in pulmonary rehabilitation. Evidence does support the use of supplemental oxygen therapy for patients with severe hypoxemia at rest or with exercise. Noninvasive ventilation may be helpful for selected patients with advanced COPD. Finally, pulmonary rehabilitation appears to benefit patients with chronic lung diseases other than COPD.

Conclusions: There is substantial new evidence that pulmonary rehabilitation is beneficial for patients with COPD and other chronic lung diseases. Several areas of research provide opportunities for future research that can advance the field and make rehabilitative treatment available to many more eligible patients in need.

Pulmonary diseases are increasingly important causes of morbidity and mortality in the modern world. The COPDs are the most common chronic lung diseases, and are a major cause of lung-related death and disability.1Pulmonary rehabilitation has emerged as a recommended standard of care for patients with chronic lung disease based on a growing body of scientific evidence. A previous set23 of evidence-based guidelines was published in 1997 as a joint effort of the American College of Chest Physicians (ACCP) and the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR). Since then, the published literature in pulmonary rehabilitation has increased substantially, and other organizations have published important statements about pulmonary rehabilitation (eg, the American Thoracic Society and the European Respiratory Society4). The purpose of this document is to update the previous ACCP/AACVPR document with a systematic, evidence-based review of the literature published since then.

In the United States, COPD accounted for 119,054 deaths in 2000, ranking as the fourth leading cause of death and the only major disease among the top 10 in which mortality continues to increase.58 In persons 55 to 74 years of age, COPD ranks third in men and fourth in women as cause of death.9However, mortality data underestimate the impact of COPD because it is more likely to be listed as a contributory cause of death rather than the underlying cause of death, and it is often not listed at all.1011 Death rates from COPD have continued to increase more in women than in men.5 Between 1980 and 2000, death rates for COPD increased 282% for women compared to only 13% for men. Also, in 2000, for the first time, the number of women dying from COPD exceeded the number of men.5

Morbidity from COPD is also substantial.5,12COPD develops insidiously over decades and because of the large reserve in lung function there is a long preclinical period. Affected individuals have few symptoms and are undiagnosed until a relatively advanced stage of disease. In a population survey in Tucson, AZ, Burrows13 reported that only 34% of persons with COPD had ever consulted a physician, 36% denied having any respiratory symptoms, and 30% denied dyspnea on exertion, which is the primary symptom. National Health and Nutrition Examination Study III data estimate that 24 million US adults have impaired lung function, while only 10 million report a physician diagnosis of COPD.5 There are approximately 14 million cases of chronic bronchitis reported each year, and 2 million cases of emphysema.14The National Center for Health Statistics for 1996 reported prevalence rates of chronic bronchitis and emphysema in older adults (eg, persons ≥ 65 years of age) of 82 per 1,000 men and 106 per 1,000 women.15 In 2000, COPD was responsible for 8 million physician office visits, 1.5 million emergency department visits, and 726,000 hospitalizations.5 COPD accounts for > 5% of physician office visits and 13% of hospitalizations.16National Health and Nutrition Examination Study III data from 1988 to 1994 indicated an overall prevalence of COPD of 8.6% among 12,436 adults (average age for entire cohort, 37.9 years).17 In the United States, COPD is second only to coronary heart disease as a reason for Social Security disability payments.

Worldwide, the burden of COPD is projected to increase substantially, paralleling the rise in tobacco use, particularly in developing countries. An analysis by the World Bank and World Health Organization ranked COPD 12th in 1990 in disease burden, as reflected in disability-adjusted years of life lost.10

For consistency throughout the document, the panel used the description of severity of COPD as recommended by the Global Initiative for Chronic Obstructive Lung Disease18and the American Thoracic Society/European Respiratory Society Guidelines19 based on FEV1, as follows: stage I (mild), FEV1 ≥ 80% predicted; stage II (moderate), FEV1 50 to 80% predicted; stage III (severe), FEV1 30 to 50% predicted; and stage IV (very severe), FEV1 < 30% predicted.

Rehabilitation programs for patients with chronic lung diseases are well-established as a means of enhancing standard therapy in order to control and alleviate symptoms and optimize functional capacity.2,4,14,20 The primary goal is to restore the patient to the highest possible level of independent function. This goal is accomplished by helping patients become more physically active, and to learn more about their disease, treatment options, and how to cope. Patients are encouraged to become actively involved in providing their own health care, more independent in daily activities, and less dependent on health professionals and expensive medical resources. Rather than focusing solely on reversing the disease process, rehabilitation attempts to reduce symptoms and reduce disability from the disease.

Many rehabilitation strategies have been developed for patients with disabling COPD. Programs typically include components such as patient assessment, exercise training, education, nutritional intervention, and psychosocial support. Pulmonary rehabilitation has also been applied successfully to patients with other chronic lung conditions such as interstitial diseases, cystic fibrosis, bronchiectasis, and thoracic cage abnormalities.21In addition, it has been used successfully as part of the evaluation and preparation for surgical treatments such as lung transplantation and lung volume reduction surgery.2226 Pulmonary rehabilitation is appropriate for any stable patient with a chronic lung disease who is disabled by respiratory symptoms. Patients with advanced disease can benefit if they are selected appropriately and if realistic goals are set. Although pulmonary rehabilitation programs have been developed in both outpatient and inpatient settings, most programs, and most of the studies reviewed in this document, pertain to outpatient programs for ambulatory patients.

The American Thoracic Society and the European Respiratory Society have recently adopted the following definition of pulmonary rehabilitation: Pulmonary rehabilitation is an evidence-based, multidisciplinary, and comprehensive intervention for patients with chronic respiratory diseases who are symptomatic and often have decreased daily life activities. Integrated into the individualized treatment of the patient, pulmonary rehabilitation is designed to reduce symptoms, optimize functional status, increase participation, and reduce health-care costs through stabilizing or reversing systemic manifestations of the disease. Comprehensive pulmonary rehabilitation programs include patient assessment, exercise training, education, and psychosocial support.4

This definition focuses on three important features of successful rehabilitation:

  1. Multidisciplinary: Pulmonary rehabilitation programs utilize expertise from various health-care disciplines that is integrated into a comprehensive, cohesive program tailored to the needs of each patient.

  2. Individual: Patients with disabling lung disease require individual assessment of needs, individual attention, and a program designed to meet realistic individual goals.

  3. Attention to physical and social function: To be successful, pulmonary rehabilitation pays attention to psychological, emotional, and social problems as well as physical disability, and helps to optimize medical therapy to improve lung function and exercise tolerance.

The interdisciplinary team of health-care professionals in pulmonary rehabilitation may include physicians; nurses; respiratory, physical, and occupational therapists; psychologists; exercise specialists; and/or others with appropriate expertise. The specific team make-up depends on the resources and expertise available, but usually includes at least one full-time staff member.27

In 1997, the ACCP and the AACVPR released an evidence-based clinical practice guideline entitled “Pulmonary Rehabilitation: Joint ACCP/AACVPR Evidence-Based Guidelines.”23 Following the approved process for the review and revision of clinical practice guidelines, in 2002 the ACCP Health and Science Committee determined that there was a need for reassessment of the current literature and an update of the original practice guideline. This new guideline is intended to update the recommendations from the 1997 document and to provide new recommendations based on a comprehensive literature review. The literature review and development of evidence tables were conducted by Carla Herrerias, MPH, the ACCP Clinical Research Analyst. The joint ACCP/AACVPR expert panel used the evidence to develop graded recommendations.

Expert Panel Composition

The guideline panel was organized under the joint sponsorship of the ACCP and the AACVPR. Andrew Ries, MD, MPH, FCCP, Chair of the 1997 panel, served as Chair of the new panel. Panel members were evenly distributed between and selected by the two organizations with a goal of making the panel multidisciplinary and geographically diverse. Drs. Casaburi, Mahler, Make, and Rochester represented the ACCP, and Drs. Bauldoff, Carlin, Emery, and ZuWallack represented the AACVPR. Five panel members (Drs. Carlin, Casaburi, Emery, Mahler, and Make) had served on the previous guideline panel. In addition to several conference calls, the panel met for one 2-day meeting to review the evidence tables and become familiar with the process of grading recommendations. Writing assignments were determined by members’ known expertise in specific areas of pulmonary rehabilitation. Each section of the guideline was assigned to one primary author and at least one secondary author. Sections were reviewed by relevant panel members when topics overlapped.

Conflict of Interest

At several stages during the guideline development period, panel members were asked to disclose any conflict of interest. These occurred at the time the panel was nominated, at the first face-to-face meeting, the final conference call, and prior to publication. Written forms were completed and are on file at the ACCP.

Scope of Work

The 1997 practice guideline on pulmonary rehabilitation focused on program component areas of lower and upper extremity training, ventilatory muscle training, and various outcomes of comprehensive pulmonary rehabilitation programs, including dyspnea, quality of life, health-care utilization, and survival. Psychosocial and educational aspects of rehabilitation were examined both as program components and as outcomes.

For this review, the panel decided to focus on studies that had been published since the previous review, again concentrating on stable patients with COPD. Since there have been many advances and new areas of investigation since the previous document was written, the panel decided to expand the scope of this review rather than just update the previous one. Topics covered in this document include the following:

  • Outcomes of comprehensive pulmonary rehabilitation programs: lower extremity exercise training; dyspnea; health-related quality of life (HRQOL); health-care utilization and economic analysis; survival; psychosocial outcomes; and long-term benefits from pulmonary rehabilitation;

  • Duration of pulmonary rehabilitation;

  • Postrehabilitation maintenance strategies;

  • Intensity of aerobic exercise training;

  • Strength training in pulmonary rehabilitation;

  • Anabolic drugs;

  • Upper extremity training;

  • Inspiratory muscle training (IMT);

  • Education;

  • Psychosocial and behavioral components of pulmonary rehabilitation;

  • Oxygen supplementation as an adjunct to pulmonary rehabilitation;

  • Noninvasive ventilation;

  • Nutritional supplementation in pulmonary rehabilitation;

  • Pulmonary rehabilitation for patients with disorders other than COPD; and

  • Summary and recommendations for future research.

Review of Evidence

The literature review was based on the scope of the work as outlined in the previous section. The literature search was conducted through a comprehensive MEDLINE search from 1996 through 2004, and was supplemented by articles supplied by the guideline panel as well as by a review of bibliographies and reference lists from review articles and other existing systematic reviews. The literature search was limited to articles published in peer-reviewed journals only in the English language, and on human subjects. Inclusion criteria primarily included a population of persons with a diagnosis of COPD determined either by physical examination or by existing diagnostic criteria; however, those with other pulmonary conditions (eg, asthma or interstitial lung disease) were also included. The search included randomized controlled trials (RCTs), metaanalyses, systematic reviews, and observational studies. The search strategy linked pulmonary rehabilitation or a pulmonary rehabilitation program with each key subcomponent, as listed in section on “Scope of Work.” To locate studies other than RCTs, such as systematic reviews and metaanalyses, those key words were used in searching MEDLINE and the Cochrane databases. Informal review articles were included only for hand searching additional references. For the purpose of this review, pulmonary rehabilitation was defined operationally as studies involving exercise training plus at least one additional component. Associated outcomes across all components were dyspnea, exercise tolerance, quality of life and activities of daily life, and health-care utilization. An initial review of 928 abstracts was conducted by the ACCP Clinical Research Analyst and the Research Specialist. Full articles (a total of 202) were formally reviewed and abstracted by the Clinical Research Analyst, and a total of 81 clinical trials were included in all evidence tables. RCTs were scored using a simplified system that was based on methods of randomization, blinding, and documentation of withdrawals/loss to follow-up. This system follows a method that is based on a 3-point scale, which rates randomization (and appropriateness), blinding (and appropriateness), and tracking of withdrawals and loss to follow-up. Studies were graded on a scale of 0 to 5.28 No formal quantitative analysis was performed due to the wide variation in methodologies reported in studies. Given the length of time required to prepare the final manuscript after the conclusion of the systematic literature review in December 2004, from which the tables were constructed, the committee was allowed to include reference to selected articles published in 2005 and 2006 in the text if the additional information provided by the newer publications was felt to be important.

Strength of Evidence and Grading of Recommendations

The ACCP system for grading guideline recommendations is based on the relationship between the strength of the evidence and the balance of benefits to risk and burden (Table 1 ).29 Simply stated, recommendations can be grouped on the following two levels: strong (grade 1); and weak (grade 2). If there is certainty that the benefits do (or do not) outweigh risk, the recommendation is strong. If there is less certainty or the benefits and risks are more equally balanced, the recommendation is weaker. Several important issues must be considered when classifying recommendations. These include the quality of the evidence that supports estimates of benefit, risks, and costs; the importance of the outcomes of the intervention; the magnitude and the precision of estimate of the treatment effect; the risks and burdens of an intended therapy; the risk of the target event; and varying patient values.

The strength of evidence is classified, based on the quality of the data, into the following three categories: high (grade A); moderate (grade B); and low (grade C). The strongest evidence comes from well-designed RCTs yielding consistent and directly applicable results. In some circumstances, high-quality evidence can be the result of overwhelming evidence from observational studies. Moderate-quality evidence is based on RCTs with limitations that may include methodological flaws or inconsistent results. Studies other than RCTs that may yield strong results are also included in the moderate-quality category. The weakest type of evidence is that from other types of observational studies. It should be noted that the ACCP Health and Science Policy Committee has endorsed the principle that most relevant clinical studies provide evidence, even though the quality of that evidence is varied. Therefore, the reasons for excluding studies should be documented.

Table 2 describes the balance of benefits to risk and burden, and the level of certainty based on this balance. As stated above, the more certain the balance, or lack thereof, the stronger the recommendation. Patient and community values are important considerations in clinical decision making and are factored into the grading process. In situations in which the benefits clearly do or do not outweigh the risks, it is assumed that nearly all patients would have the same preferences. For weaker recommendations, however, there may not be consistency in patient preferences.

In addition to recommendations, the committee included several statements when it thought that there was insufficient evidence to make a specific recommendation. These statements are included along with the recommendations but are not graded.

As currently practiced, pulmonary rehabilitation typically includes several different components, including exercise training, education, instruction in various respiratory and chest physiotherapy techniques, and psychosocial support. For this review, comprehensive pulmonary rehabilitation was defined as an intervention that includes one or more of these components beyond just exercise training, which is considered to be an essential, mandatory component.

In addition to the clinical trials reviewed in the evidence tables in this document, several systematic reviews and metaanalyses have been published within the past decade that support the beneficial effects from comprehensive pulmonary rehabilitation programs. In a Cochrane Review published in 2006, Lacasse30analyzed 31 RCTs in patients with COPD and concluded that rehabilitation forms an important component of the management of COPD. They reported statistically and clinically significant improvements in important domains of quality of life (i.e., dyspnea, fatigue, emotions, and patient control over disease). Improvement in measures of exercise capacity were slightly below the threshold for clinical significance. Similarly, after a systematic review, Cambach and colleagues31 identified 18 articles for inclusion in a metaanalysis of outcome measures of exercise capacity and HRQOL in patients with COPD. They found significant improvements for exercise measures of maximal exercise capacity, endurance time, and walking distance, and for HRQOL measures in all dimensions of the Chronic Respiratory Disease Questionnaire (CRDQ) [ie, dyspnea, fatigue, emotion, and mastery]. Improvements in maximal exercise capacity and walking distance were sustained for up to 9 months after rehabilitation.

Lower Extremity Exercise Training
Dyspnea:

In the previous evidence-based review document23 the 1997 guidelines panel concluded that the highest strength of evidence (A) supported the recommendation for including lower extremity exercise training as a key component of pulmonary rehabilitation for patients with COPD. In addition, the panel concluded that there was high-grade evidence (A) that pulmonary rehabilitation improves the symptom of dyspnea in patients with COPD. This panel concluded that the evidence presented in Table 3 in this document further strengthens those conclusions and recommendations.

Recommendations

1. A program of exercise training of the muscles of ambulation is recommended as a mandatory component of pulmonary rehabilitation for patients with COPD. Grade of recommendation, 1A

2. Pulmonary rehabilitation improves the symptom of dyspnea in patients with COPD: Grade of recommendation, 1A

HRQOL

Regarding changes in HRQOL, the previous panel concluded that there was B level strength of evidence supporting the recommendation that “pulmonary rehabilitation improves health-related quality of life in patients with COPD.” Based on the current review, this panel believes that the additional published literature now available strengthens support for this conclusion and upgrades the evidence to grade A. In this document, the term HRQOL will be used interchangeably with the term health status.

In one of the larger RCTs reported (200 patients), Griffiths and colleagues32reported significant improvements in HRQOL 1 year after a 6-week pulmonary rehabilitation program. Troosters and colleagues33reported sustained improvement in HRQOL over 18 months after patients participated in a 6-month outpatient pulmonary rehabilitation program compared with the decline observed in the control group. The study reported by Green and colleagues34reported improvement in HRQOL after pulmonary rehabilitation and found that improvements after a 7-week intervention were greater than those after 4 weeks of pulmonary rehabilitation. Strijbos and colleagues35reported significant improvement in reported well-being after pulmonary rehabilitation that was maintained over 18 months in rehabilitation-treated subjects, while most patients in the control group felt unchanged or worse. Foglio and colleagues36reported sustained improvements in HRQOL up to 2 years after pulmonary rehabilitation. In a study of early pulmonary rehabilitation after hospital discharge for an exacerbation of COPD, Man and colleagues reported significant improvements in HRQOL measures. Finnerty and colleagues37reported marked improvements in HRQOL after pulmonary rehabilitation that persisted for 6 months. Similar findings were reported by Bendstrup and colleagues.38In the study reported by Wedzicha and colleagues,39which stratified patients according to baseline dyspnea, improvement in HRQOL after pulmonary rehabilitation was observed in patients with moderate dyspnea (Medical Research Council [MRC] score, 3 or 4) but not in control subjects or patients with severe baseline dyspnea (MRC score, 5). The study by Ries and colleagues40evaluated a maintenance program after pulmonary rehabilitation. However, observational results after pulmonary rehabilitation that had been administered to all patients before randomization demonstrated consistent improvements in several different measures of both general and disease-specific measures of HRQOL. Guell and colleagues41 reported significant improvement in HRQOL that persisted, although diminished, for up to 2 years of follow-up after the pulmonary rehabilitation intervention.

Of the studies reported in Table 3, only one small study by White and colleagues42reported only modest improvements in measured HRQOL that did not consistently reach statistically or clinically significant levels. In addition to the studies reported in Table 3, which generally were performed in single specialized centers, two observational studies44 provide strong evidence of the effectiveness of pulmonary rehabilitation as routinely practiced in clinical centers. Although neither of these studies4344 was an RCT, they provide important information regarding the generalizability of the practice of pulmonary rehabilitation beyond specialized centers and as currently practiced in the general medical community in the United States. A multicenter evaluation of pulmonary rehabilitation in 522 patients in nine centers throughout California43reported consistent improvements in symptoms of dyspnea and HRQOL after pulmonary rehabilitation. Similar findings were reported in a multicenter observational study in Connecticut.44 In this study, significant improvement was reported in the pulmonary functional status scale in 164 patients in 10 centers and in the CRDQ in 60 patients in 3 centers. Also, in the National Emphysema Treatment Trial (NETT),26 a randomized study that evaluated lung volume reduction surgery in 1,218 patients with severe emphysema, all subjects were required to complete a pulmonary rehabilitation program as part of the eligibility requirements before randomization. Pulmonary rehabilitation was conducted at the 17 NETT centers as well as at 539 satellite centers throughout the United States. Observational results demonstrated significant improvements in measures of exercise tolerance, dyspnea, and HRQOL after rehabilitation that were quite comparable among the specialized NETT centers and the largely community-based satellite centers.

Recommendation

3. Pulmonary rehabilitation improves HRQOL in patients with COPD. Grade of recommendation, 1A

Health-Care Utilization and Economic Analysis

Regarding changes in health-care utilization resulting from pulmonary rehabilitation, the previous panel concluded that there was B level strength of evidence supporting the recommendation that “pulmonary rehabilitation has reduced the number of hospitalizations and the number of days of hospitalization for patients with COPD.”

In the current review, some additional information is available about changes in health-care utilization after pulmonary rehabilitation. In the study by Griffiths and colleagues,32 over 1 year of follow-up the number of patients admitted to the hospital was similar in both the pulmonary rehabilitation group and the control group (40 of 99 vs 41 of 101 patients); however, the number of days spent in the hospital was significantly lower in the rehabilitation patients (10.4 vs 21.0 days, respectively). In a subsequent cost-utility economic analysis of the results in this pulmonary rehabilitation trial, Griffiths and colleagues45 found that the cost per quality-adjusted life-years indicated that pulmonary rehabilitation was, in fact, cost-effective and would likely result in financial benefits to the health-care system (quality-adjusted life-year is a measure of effectiveness that is commonly used in cost-effectiveness analyses, reflecting survival adjusted for quality of life, or the value that individuals place on expected years of life). In the trial reported by Foglio and colleagues,36 results indicated a significant decrease in yearly hospitalizations and exacerbations > 2 years after pulmonary rehabilitation.

Goldstein and colleagues46conducted a cost analysis that was associated with an RCT of a 2-month inpatient pulmonary rehabilitation program (followed by 4 months of outpatient supervision) that produced statistically and clinically significant improvements in measures of HRQOL and exercise capacity. Although the cost analysis in this study was driven largely by the inpatient phase of the program and, as such, is not applicable to the large majority of outpatients programs, the authors found cost-effectiveness ratios for the CRDQ component measures to range from $19,011 to $35,142 (in Canadian dollars) per unit difference. Even with the added costs associated with the inpatient program, these cost/benefit ratios are within a range that has been typically considered to represent reasonable cost-effectiveness for other widely advocated health-care programs.47

In a small randomized trial of early pulmonary rehabilitation after hospitalization for acute exacerbation, Man and colleagues48reported a significant reduction in emergency department visits and a trend toward reduced numbers of hospital admissions and days spent in the hospital over the 3 months after hospital discharge in the pulmonary rehabilitation group compared to the usual-care group. Also, in a multicenter randomized trial of a self-management program of patients with severe COPD, Bourbeau and colleagues49 reported a significant reduction in the numbers of hospital admissions and days spent in the hospital in the year following the intervention compared to the usual-care control group.

In a multicenter, observational evaluation43 of the effectiveness of pulmonary rehabilitation in centers throughout California (not included in Table 3), self-reported measures of health-care utilization were found to decrease substantially over 18 months of observation after the rehabilitation intervention. In the 3-month period prior to pulmonary rehabilitation, 522 patients reported 1,357 hospital days (2.4 per patient), 209 urgent care visits (0.4 per patient), 2,297 physician office visits (4.4 per patient), and 1,514 telephone calls to physicians (2.7 per patient). Over the 18 months after rehabilitation, the average per patient reported health-care utilization (in the past 3 months) was reduced approximately 60% for hospital days, 40% for urgent care visits, 25% for physician office visits, and 30% for telephone calls. It should be recognized that the results of an observational, noncontrolled study like this may be influenced by the selection of patients for pulmonary rehabilitation shortly after an exacerbation or episode of increased health-care utilization.

Recommendations

4. Pulmonary rehabilitation reduces the number of hospital days and other measures of health-care utilization in patients with COPD. Grade of recommendation, 2B

5. Pulmonary rehabilitation is cost-effective in patients with COPD. Grade of recommendation, 2C

Survival

The previous panel concluded that there was little evidence (strength of evidence, C) regarding survival after pulmonary rehabilitation and made the recommendation that “pulmonary rehabilitation may improve survival in patients with COPD.” Only one RCT50 of pulmonary rehabilitation was included in the previous review. In that study of 119 patients, Ries and colleagues50 reported 11% higher survival over 6 years after comprehensive pulmonary rehabilitation (67%) compared with an education control group (56%). This difference was not statistically significant. Other evidence for improved survival was derived from nonrandomized and observational studies. This lack of evidence does not necessarily indicate that pulmonary rehabilitation has no effect on survival, but in order to be reasonably powered to detect an effect of this magnitude the sample size would have to be a magnitude larger than those found in existing studies. The timed walk distance and MRC-rated dyspnea do improve with pulmonary rehabilitation, and these variables are correlated with survival in patients with COPD.

In the current review, few additional data were found regarding the effect of pulmonary rehabilitation on survival. Similar to previous published studies, the trial reported by Griffiths and colleagues32 that followed 200 patients over 1 year found fewer deaths in the rehabilitation group (6 of 99 patients) compared with the control group (12 of 101 patients).

Recommendation

6. There is insufficient evidence to determine whether pulmonary rehabilitation improves survival in patients with COPD. No recommendation is provided.

Psychosocial Outcomes

Regarding psychosocial outcomes of pulmonary rehabilitation, the previous panel concluded that “scientific evidence was lacking” (strength of evidence, C). Reviews of the research literature pertaining to psychosocial outcomes of pulmonary rehabilitation programs indicate that comprehensive pulmonary rehabilitation is generally associated with enhanced psychological well-being (ie, reduced distress) and improved quality of life.5152 In addition, it has been found that increased self-efficacy associated with exercise may mediate the effect of exercise rehabilitation on quality of life.53Other positive psychosocial outcomes of exercise rehabilitation include improved cognitive function,5456 reduced symptoms of anxiety32,55 and depression,32 and improved patient perceptions of positive consequences of the illness.57

In the current review of randomized studies, Griffiths and colleagues32 reported reduced symptoms of anxiety and depression following a 6-week pulmonary rehabilitation program, with symptoms of depression remaining significantly reduced at the 12-month follow-up. Emery and colleagues55 found reduced anxiety and improved cognitive function following a 10-week pulmonary rehabilitation intervention. In a study of 164 patients participating in pulmonary rehabilitation prior to being randomly assigned to a long-term follow-up intervention, Ries and colleagues40 observed significant improvements in measures of depression and self-efficacy for walking immediately following the 8-week pulmonary rehabilitation program.

Recommendation

7. There are psychosocial benefits from comprehensive pulmonary rehabilitation programs in patients with COPD. Grade of recommendation, 2B

Long-term Benefits From Pulmonary Rehabilitation

The formal component of most pulmonary rehabilitation programs is of relatively short duration, usually ranging from 6 to 12 weeks. Regarding the issue of long-term benefits following the short-term intervention, the previous panel did not specifically address this topic but recommended it as an important area for future research. Since that time, additional important studies have addressed this topic. The next section discusses the issue of the duration of pulmonary rehabilitation treatment (ie, beyond 12 weeks).

Several clinical trials of 6 to 12 weeks of comprehensive pulmonary rehabilitation that have followed patients over a longer term have found that benefits typically persist for about 12 to 18 months after the intervention but gradually wane thereafter. In many ways, this is surprising given the severity of illness for many of these patients with chronic lung disease and the complex set of behaviors incorporated into pulmonary rehabilitation (eg, exercise training, breathing control techniques, complex treatment regimens with medications, use of supplemental oxygen, and relaxation or panic control techniques). More recent clinical trials substantiate these findings (Table 4 ).

Griffiths and colleagues32 reported improvements in measures of exercise tolerance, HRQOL, anxiety, and depression after pulmonary rehabilitation that remained significant but declined gradually over 1 year of follow-up. The study reported by Wijkstra and colleagues58evaluated the effects of weekly vs monthly follow-up over the 18 months after pulmonary rehabilitation in a small sample of patients with COPD (n = 36). They reported no long-term improvement in exercise tolerance in the two experimental groups, although this was better than the decline observed in the control group. There were, however, more sustained improvements in dyspnea. Engstrom and colleagues59 reported sustained improvement in exercise tolerance at 12 months after pulmonary rehabilitation with minimal improvements in either a general or disease-specific measure of HRQOL (although there was a trend for worsening HRQOL in the control group). Strijbos and colleagues35 reported significant improvement in reported well-being after pulmonary rehabilitation that was maintained over 18 months (compared to most control subjects who reported being unchanged or worse). The study reported by Guell and colleagues41 also found persistent, but diminished, benefits in measures of exercise tolerance, dyspnea, and HRQOL over the 2 years of follow-up after pulmonary rehabilitation.

The study reported by Ries and colleagues40 examined the effects of a telephone-based maintenance program for 1 year after a short-term rehabilitation intervention. The experimental effects of the maintenance program are discussed in a subsequent section on postrehabilitation maintenance. However, as an observational study, it is notable that the control group (without postprogram maintenance) demonstrated a progressive decline in benefits over 2 years of follow-up. Another multicenter observational evaluation of the effectiveness of pulmonary rehabilitation in centers throughout California (not included in Table 3),43 found that improvements in symptoms of dyspnea, HRQOL, and indexes of health-care utilization declined over 18 months but still remained above baseline levels.

Recommendation

8. Six to twelve weeks of pulmonary rehabilitation produces benefits in several outcomes that decline gradually over 12 to 18 months. Grade of recommendation, 1A. Some benefits, such as HRQOL, remain above control levels at 12 to 18 months. Grade of recommendation, 1C

There is no consensus of opinion regarding the optimal duration of the pulmonary rehabilitation intervention. From the patient’s perspective, the optimal duration should be that which produces maximal effects in the individual without becoming burdensome. Significant gains in exercise tolerance, dyspnea, and HRQOL have been observed following inpatient pulmonary rehabilitation programs as short as 10 days60and after outpatient programs as long as 18 months.61Shorter program duration has the potential to reduce the cost per patient served and to spread limited resources.62 On the other hand, longer program duration may produce greater gains and improved maintenance of benefits. This section will examine longer term pulmonary rehabilitation interventions (ie, beyond 12 weeks of treatment).

Successful pulmonary rehabilitation requires complex behavioral changes for which the patients’ competence and adherence may be facilitated by longer exposure to treatment interventions and interactions with staff who provide reinforcement, encouragement, and coaching. These changes include incorporating regular exercise into the patient’s lifestyle; the use of breathing techniques, pacing and energy conservation strategies; and the use of medications and equipment, supplemental oxygen, and psychosocial adaptations. A number of external factors also influence program duration including health-care systems and reimbursement policies, access to programs, level of functional disability, health-care provider referral patterns, and the ability of individual patients to make progress toward treatment goals.

Few clinical trials have focused on the impact of program duration on rehabilitation outcomes, but existing data suggest that gains in exercise tolerance may be greater following longer programs (Table 5 ). For example, two other randomized trials compared 3 vs 18 months of low-intensity exercise training in pulmonary rehabilitation.6364 Berry and colleagues63demonstrated that the longer intervention led to a 6% increase in the 6-min walk distance, a 12% reduction in self-reported disability, and faster completion of stair climbing and overhead tasks. Foy and colleagues64showed that only male patients achieved greater gains in CRDQ scores following the 18-month program (compared to the 3-month program). In a 2005 published prospective trial involving seven outpatient programs (not in Table 5), Verrill and colleagues65 demonstrated that patients achieved significant gains in exercise tolerance (6-min walk distance), dyspnea (University of California, San Diego Shortness of Breath Questionnaire), and health status (Medical Outcomes Study 36-item Short Form and the quality-of-life index) after 12 weeks of pulmonary rehabilitation. Following an additional 12 weeks of rehabilitation, exercise tolerance but not health status or dyspnea outcomes improved further, suggesting that program duration may not impact all outcomes equally.

Also in support of longer term exercise training, Troosters and colleagues33 demonstrated that a 6-month outpatient pulmonary rehabilitation program composed of moderate-to-high-intensity aerobic and strength exercise training led to significant improvements in exercise performance and quality of life. Although this study did not compare the 6-month program with a shorter one, the benefits gained following the 6-month training program persisted 18 months after the completion of rehabilitation. This contrasts with the results of other studies35,50,66 of pulmonary rehabilitation of shorter than 6 months duration in which benefits tended to decline progressively over the year following rehabilitation. Likewise, in the study by Guell and colleagues41(Table 4) a 12-month intervention (6 months of daily rehabilitation followed by 6 months of weekly supervision) led to gains in exercise tolerance, dyspnea, and health status that persisted over the 1 year after rehabilitation, although even these benefits tended to decline gradually over the second year of follow-up.

Green and colleagues34 also demonstrated that patients with severe COPD achieved greater improvements in treadmill endurance, incremental shuttle walk distance, and quality of life following a 7-week outpatient pulmonary rehabilitation program compared with an identical program of only 4 weeks duration. However, patients who underwent the 4-week program were not reassessed at the 7-week time point to enable the direct comparison of outcomes.

A more recent trial (not in Table 5) readdressed this issue in a larger cohort of patients. Sewell and colleagues67 randomized 100 patients with moderate-to-severe COPD (mean FEV1, 1.13 L) to receive 4 vs 7 weeks of outpatient rehabilitation. All patients were assessed at baseline, at the end of the rehabilitation intervention, and 6 months later. Patients in the 4-week training group were also evaluated at 7 weeks. Patients in both groups had significant improvements in exercise tolerance and health status. This study contrasts with the results of other published studies mentioned above in that it showed that the shorter 4-week intervention produced gains in exercise tolerance at both the 7-week and 6-month follow-up time periods that were comparable to those following the longer 7-week program. Finally, in an older trial Wijkstra and colleagues,61 showed that patients who underwent 18 months of home-based rehabilitation had greater sustained improvements in quality of life compared with patients who received twice-weekly rehabilitation over a 3-month period, but no difference was noted between groups in the magnitude of gains in the 6-min walk distance.

Overall, although some studies suggest that the duration of the pulmonary rehabilitation program impacts exercise tolerance improvement, it is less clear that other outcomes such as health status or dyspnea are similarly affected by program duration. Other studies60,67 have demonstrated that even programs of short duration (ie, 10 days to 4 weeks) can produce significant benefits as well. Moreover, the effect of program duration on patient abilities to perform activities of daily living (ADLs) is uncertain. The clinical benefits of pulmonary rehabilitation may depend as much on program site and content as on duration.,62 Thus, given the variations in types of rehabilitation programs and differences in clinical study design, patient populations, health systems in different countries, program location, and program content, it is not possible at this time to draw firm conclusions regarding the optimal duration of pulmonary rehabilitation treatment.

Recommendation

9. Longer pulmonary rehabilitation programs (beyond 12 weeks) produce greater sustained benefits than shorter programs. Grade of recommendation, 2C