Pulmonary Rehabilitation* Joint ACCP/AACVPR Evidence-Based Clinical Practice Guidelines

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

Disclosures

CHEST. 2007;131(5):4S-42S. 

In This Article

IMT

In general, patients with COPD have weak inspiratory muscles.[132,133] In fact, biopsy specimens from patients with mild-to-moderate COPD show reduced force generation per cross-sectional area.[134] The major clinical consequences of inspiratory muscle weakness for patients are breathlessness and exercise impairment. The rationale for IMT is that increasing the strength and/or endurance of the respiratory muscles has the potential to improve these clinical outcomes. To date, clinical trials of IMT have been performed in endurance athletes, in patients with chronic respiratory diseases (ie, asthma, cystic fibrosis, and COPD), chronic heart failure, chronic cervical spinal cord injury, and muscular dystrophy, before cardiothoracic surgery, and to assist weaning from mechanical ventilatory support.

The 1997 guidelines panel concluded that "the scientific evidence at the present time does not support the routine use of ventilatory muscle training as an essential component of pulmonary rehabilitation" and that "ventilatory muscle training may be considered in selected patients with COPD who have decreased respiratory muscle strength and breathlessness" (strength of evidence, B).

In the current review, six investigations of IMT were identified ( Table 8 )[137,206,207,208,209,210] that met the following criteria: randomized trial involving patients with COPD and a treatment and a control group; use of a resistance, threshold, or flow device for IMT; and inclusion of appropriate physiologic (ie, inspiratory muscle strength [maximal inspiratory pressure (PImax)] and/or endurance and exercise performance) and clinical (ie, dyspnea ratings and/or health status) outcome measures. These six studies included a total of 169 patients with COPD (range, 17 to 32 subjects per study) who completed the trials, which lasted from 2 months to 1 year in duration. In addition, a metaanalysis by Lotters and colleagues[135] and a review article by Lisboa and Borzone[136] were also considered.

The 1997 guidelines panel raised various concerns about the methodology of studies evaluating IMT. For example, one question regarding the previous studies was: "Is the training stimulus adequate to induce an expected physiologic response?" All of the six new studies that were reviewed ( Table 8 ) provided subjects with an appropriate training stimulus such that the respective IMT group achieved improvement in respiratory muscle function compared with the control group.

Another key concern is the type of IMT. The major training methods are threshold loading, resistive breathing, and targeted flow. Five of the six new studies[206,207,208,209,210] used threshold loading, which has the advantage of being independent of inspiratory flow rate but requires a build up of negative pressure before flow begins. In addition, threshold loading enhances the velocity of inspiratory muscle contraction, which appears favorable by shortening inspiratory time, thus allowing more time for exhalation and lung emptying. The sixth study[137] trained subjects with an incentive flowmeter that provided visual feedback.

One of the most important questions relates to the types of patients with COPD (ie, phenotypes) concerns who should be considered for IMT. In the six new trials ( Table 8 ), [137,206,207,208,209,210] patients were recruited based on a diagnosis of COPD and a willingness to participate in the study. No specific patient phenotypes, such as stage of COPD, evidence of inspiratory muscle weakness, degree of hyperinflation, severity of breathlessness, level of exercise impairment, and/or reduced health status, were considered for inclusion or exclusion criteria in these studies. In a metaanalysis, Lotters and colleagues[135] found that neither the degree of severity of COPD nor hyperinflation had any effect on the efficacy of IMT. However, subgroup analysis revealed that those patients with inspiratory muscle weakness (ie, PImax, ≤60 cm H2O) improved PPImax significantly more with IMT combined with exercise training compared to patients without inspiratory muscle weakness.

The consideration of outcome measures is also important to assess the benefits of IMT. Overall, the six investigations summarized in Table 8[137,206,207,208,209,210] show consistent improvements in inspiratory muscle function, increases in exercise performance, and reductions in dyspnea. These data generally support the findings of the metaanalysis by Lotters and colleagues[135] that IMT by itself significantly increased inspiratory muscle strength and endurance, significantly improved dyspnea related to ADLs and during exercise, and showed a nonsignificant trend for an increase in exercise capacity.

Collectively, the positive results of the six new studies[137,206,207,208,209,210] ( Table 8 ) provide further support for the efficacy (both physiologic and patient-centered outcomes) of IMT. However, each study was performed at a single institution and included relatively small numbers of patients with COPD. Based on this information, the panel continues to recommend that IMT be considered in selected patients with COPD who have decreased inspiratory muscle strength and breathlessness despite receiving optimal medical therapy. The panel believes that a large-scale, multicenter RCT should be performed with appropriate statistical power to more completely examine the role of IMT in treating patients with COPD. Appropriate patient characteristics, training methodologies, and outcome measures are important considerations.

16. The scientific evidence does not support the routine use of IMT as an essential component of pulmonary rehabilitation. Grade of recommendation, 1B

The 1997 guidelines panel agreed that "education is generally considered to be a necessary, but not sufficient, part of pulmonary rehabilitation" but did not review the topic independent of the other components because it could not identify a sufficient number of studies that were focused solely on education. The panel reviewed education along with the psychosocial and behavioral components and recommended that "although scientific evidence is lacking, expert opinion supports the inclusion of educational and psychosocial interventions as components of comprehensive pulmonary rehabilitation programs for patients with COPD" (strength of evidence, C).

Patient education is a central component of most pulmonary rehabilitation programs. Education classes are generally conducted in a lecture/discussion format and may cover a wide variety of topics regarding the management of chronic lung disease. The scientific evidence for education in the 1997 guidelines was based on four randomized studies and one observational study.[138,139,140,141,142] Three of these studies[138,139,140] demonstrated mild improvement in dyspnea. One of these studies[140] compared dyspnea self-management to health education as the control, finding that the self-management group reported deceased dyspnea on baseline dyspnea index/transitional dyspnea index. In addition, both forms of education resulted in significant improvement in dyspnea. Conflicting results were reported in the two additional studies reviewed.[141,142] One study[141] found that education imparted no benefit on coping skills, while the second study[142] reported increased psychological distress following an education intervention.

In the current review, four new RCTs were identified.[49,55,143,144] The results of all of these studies demonstrate that education alone has no independent benefit ( Table 9 ).

In the study by Emery and colleagues,[55] a three-group design tested comprehensive pulmonary rehabilitation vs education and stress management (ESM) vs a waiting-list group in 79 stable patients with COPD using blinded data collectors. The findings were that the pulmonary rehabilitation group demonstrated significant improvements in endurance exercise, maximum VO 2, psychological well-being, and illness-related impairment when compared to the education group (p < 0.05). Significant improvement was seen over time for anxiety as well as cognitive function in the pulmonary rehabilitation group vs the education group (p < 0.05). However, all groups achieved significant improvement in mental efficiency over time. The authors concluded that comprehensive pulmonary rehabilitation produced significant improvements in endurance exercise, anxiety, and cognitive performance when compared to either the education-alone group or to the waiting-list group.

The study by Stulbarg and colleagues[144] also used a three-group design evaluating education in the form of (1) dyspnea self-management alone vs (2) dyspnea self-management with minimal exercise training (4 sessions) vs (3) dyspnea self-management with extensive exercise training (24 sessions) in 115 patients with moderate-to-severe COPD with single blinding. Significant improvement was seen in the training group for 6-min walk distance (p < 0.001). Both the program-exposure group and the exercise-training group reported significant improvement in shortness of breath that was not seen in the self-management group (p < 0.04). Improvements in CRDQ subscales were seen primarily in the exercise-training group (p < 0.003), supporting the hypothesis that improvement in dyspnea was related to the number of exercise sessions undertaken. No improvements in dyspnea or function were seen in the self-management group.

In the third study by Ringbaek and colleagues,[143] an 8-week pulmonary rehabilitation program plus education was compared to conventional care in 45 stable patients with moderate COPD without the blinding of either the participants or the research staff. No significant differences were seen between the group receiving pulmonary rehabilitation plus education compared to the control group. Of note, the authors concluded that the absence of significant differences might be due to the brevity of the program (8 weeks), the selection of patients with moderate COPD, or type II error.

In the final study by Bourbeau and colleagues,[49] a self-management program was compared to usual care in 191 patients with COPD. The 2-month program was composed of weekly visits by nurses or allied health professionals including exercise evaluation and home-based instruction in an exercise-training program. Monthly telephone calls were conducted in months 3 to 12. The number of hospital admissions related to COPD exacerbations was reduced significantly in the intervention group vs the usual-care group (40%), as well as the number of hospital admissions related to other problems (57%). In addition, significant reductions in the numbers of emergency department visits (41%) and unscheduled physician visits (59%) were seen. These results suggest that a self-management program provided by health professionals reduced health-care service utilization.

In summary, there continues to be limited research that is specific to the impact of education on the key outcomes of pulmonary rehabilitation in patients with COPD. Nevertheless, current practice and expert opinion suggest that there are important benefits of patient education, independent of pulmonary rehabilitation, including active patient participation in a partnership with health-care providers to achieve collaborative self-management and patient adherence to health-enhancing behaviors. Patient education is included as an important recommendation in current clinical practice guidelines for COPD.[18,145]

Patient education remains an integral component of comprehensive pulmonary rehabilitation, possibly limiting the ability to differentiate the benefits of education alone. Discriminating the effect of educational topics vs exercise is difficult as they are generally administered together and appear to be highly related. The previous 1997 guidelines panel thought that education outside of a comprehensive pulmonary rehabilitation program was not sufficient to improve the well-being of patients with COPD. The new evidence on using education and self-management education supports this conclusion, since none of the studies found a benefit for education alone in the absence of exercise training.

17. Education should be an integral component of pulmonary rehabilitation. Education should include information on collaborative self-management, and the prevention and treatment of exacerbations. Grade of recommendation, 1B

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.

processing....