Correspondence

Cardiac Rehabilitation

N Engl J Med 2002; 346:379-380January 31, 2002

Article

To the Editor:

In his review, Ades (Sept. 20 issue)1 describes the benefits of cardiac rehabilitation in patients with coronary heart disease. He notes the improvement that takes place with cardiac rehabilitation in a range of psychological factors and symptoms, including anxiety, emotional stress, lack of self-confidence, depression, social isolation, and patient-reported quality of life. Ades reports that when cardiac rehabilitation specifically includes psychosocial management, greater reductions in cardiac risk factors and morbidity and mortality are evident.

We have found in our clinical work in cardiac rehabilitation that coexisting psychiatric symptoms and disorders appear to play a critical part in influencing the psychosocial status of patients with coronary heart disease and the outcomes of cardiac rehabilitation. There is accumulating evidence of distinct pathophysiologic pathways associated with various psychiatric symptoms and disorders that have also been shown to be independent risk factors for coronary heart disease. We believe that the lack of critical evaluation of the psychological symptoms of patients with coronary heart disease, in terms of diagnosable psychiatric disorders with concomitant treatment algorithms, results in underdiagnosis and undertreatment of these psychiatric disorders.

We agree with Ades that psychosocial assessment of all patients with recently diagnosed coronary heart disease is needed, but we believe that the use of a standardized instrument that assesses the presence or absence of a wide range of psychiatric illnesses is a critical component of the evaluation of these patients. Only with a comprehensive assessment of psychiatric disorders will the full benefit of a multifactorial risk-reduction approach to the secondary prevention of coronary heart disease be realized.

Bettina Bankier, M.D.
Andrew B. Littman, M.D.
Harvard Medical School, Boston, MA 02115
bbankier@partners.org

1 References

1. 1

   Ades PA. Cardiac rehabilitation and secondary prevention of coronary heart disease. N Engl J Med 2001;345:892-902
   Full Text | Web of Science | Medline

To the Editor:

In his review of cardiac rehabilitation, Ades claims that “it has not been determined whether a cardiac-rehabilitation program that consists of exercise alone reduces mortality in current patient populations.” A brief search of the Cochrane Library might have helped him. A recent systematic review of 34 trials of exercise-based cardiac rehabilitation, including 20 trials reported since 1990 and involving a total of 8440 patients, shows an overall reduction in mortality with this type of rehabilitation.1 Ades's review is nonsystematic in its coverage and consequently runs the risk of biased assessment of the value of interventions. Systematic reviewing of the literature, particularly with the use of methods defined by the Cochrane Collaboration, has developed as a rational means to reduce the biases associated with traditional narrative reviews.2 Evaluation of the effectiveness of treatment should always be guided by the best available evidence, starting with systematic reviews of large, well-conducted, randomized controlled trials.

Karen Rees, Ph.D.
Shah Ebrahim, F.R.C.P.
University of Bristol, Bristol BS8 2PR, United Kingdom
karen.rees@bristol.ac.uk

for the Cochrane Heart Group

2 References

1. 1

   Jolliffe JA, Rees K, Taylor RS, Thompson D, Oldridge N, Ebrahim S. Exercise-based rehabilitation for coronary heart disease (Cochrane Review). Cochrane Database Syst Rev 2001;1:CD001800-CD001800
   Medline

2. 2

   Egger M, Davey Smith G, O'Rourke K. Rationale, potentials and promise of systematic reviews. In: Egger M, Davey Smith G, Altman DG, eds. Systematic reviews in health care: meta-analysis in context. 2nd ed. London: BMJ Books, 2001:3-19.
   

Author/Editor Response

Dr. Ades replies:

To the Editor: I agree with Bankier and Littman that psychosocial assessment is needed in all patients with recently diagnosed coronary heart disease. The cardiac-rehabilitation program is one obvious setting in which this should occur. Certain psychological characteristics, such as depression and social isolation, are associated with poor outcome and predictably improve with rehabilitation. Although treatment has not definitively been shown to decrease mortality from cardiac causes or overall mortality, an improvement in health-related quality of life with rehabilitation is predictable. Furthermore, depression or other psychological conditions often impede patients from taking preventive medications such as aspirin, beta-blockers, or lipid-lowering drugs or from following a nutritional or exercise program.

As suggested by Rees and Ebrahim, I read the very thorough Cochrane Review entitled “Exercise-Based Rehabilitation for Coronary Heart Disease.”1 Its focus is to compare the value of interventions consisting of exercise alone with comprehensive cardiac rehabilitation in terms of specific outcomes, such as overall mortality and mortality from cardiac causes. Most of the patients in this analysis did not receive exercise-only interventions. With regard to overall mortality, only three studies of exercise alone reported since 1990 (and involving 554 patients) are included in the review, and they are not assessed in a separate statistical analysis. According to the data in those studies, the mortality rate since 1990 in patients undergoing exercise alone is 8.1 percent, as compared with a mortality rate of 9.2 percent in controls; the difference is not significant (P=0.64).

In view of lower overall mortality rates among patients with coronary disease since the 1980s, even if contemporary exercise-only rehabilitation provides a roughly 25 percent reduction in mortality, the sample size required to demonstrate this benefit needs to be far greater. I concur with the comment in the Cochrane Review that “the incremental benefit of cardiac rehabilitation on mortality in a world where the majority of patients will receive thrombolysis, aspirin, statins and increasingly ACE [angiotensin-converting–enzyme] inhibitors has not been studied adequately.”1 A lack of more recent data on exercise-only rehabilitation, however, should not interfere with the evolution of rehabilitation programs into “secondary prevention centers,” which, in addition to guiding exercise programs, are actively involved in the measurement and treatment (by pharmacologic and lifestyle approaches) of risk factors such as hyperlipidemia and hypertension according to well-defined treatment goals.2

Philip A. Ades, M.D.
University of Vermont College of Medicine, Burlington, VT 05405
philip.ades@vtmednet.org

2 References

1. 1

   Jolliffe JA, Rees K, Taylor RS, Thompson D, Oldridge N, Ebrahim S. Exercise-based rehabilitation for coronary heart disease (Cochrane Review). Cochrane Database Syst Rev 2001;1:CD001800-CD001800
   Medline

2. 2

   Smith SC, Blair SN, Bonow RO, et al. AHA/ACC guidelines for preventing heart attack and death in patients with atherosclerotic cardiovascular disease: 2001 update. J Am Coll Cardiol 2001;38:1581-1583
   CrossRef | Web of Science | Medline