Background

Cardiac rehabilitation (CR) is a comprehensive secondary prevention program that has evolved as a standardized component of the cardiovascular armamentarium. Whereas CR originated as an exercise program primarily for middle-aged male patients with coronary heart disease (CHD),¹ usually after a myocardial infarction (MI) and/or coronary artery bypass surgery (CABG), the range of eligible diagnoses and applications for CR has broadened over time. It is now a multidimensional treatment designed to promote and facilitate physical activity and healthful lifestyle in the context of known cardiovascular disease (CVD), with tremendous relevance for older populations.²

More people are living longer, and the biology of aging in this expanding senior population is intrinsically conducive to many types of CVD (e.g., CHD as well as heart failure [HF], valvular heart disease [VHD]) for which CR is now indicated.^3,4 Moreover, older adults are more likely to experience unique consequences from CVD and CVD management for which CR can be especially useful. Deconditioning, atypical symptoms, management conundrums, and poor adherence are all more likely in older age. Such vulnerabilities can arise when treatment goes smoothly (due to increased susceptibility to deconditioning and post-hospitalization syndrome with age) and they are especially likely if and when common difficulties arise (e.g., through the compounding effects of concurrent diseases, delirium, and prolonged lengths of stay), all of which are everyday scenarios among older CVD patients.^5,6

Unique Relevance of CR for Older Adults

Cardiac rehabilitation provides opportunities to contend with predictable geriatric intricacies in older patients with CVD, including 1) multimorbidity (multiple cardiac and non-cardiac diseases occurring in combination), 2) polypharmacy (multiple new medications in the context of age-related changes in pharmacokinetics and pharmacodynamics that predispose to side effects and iatrogenesis), 3) detrimental processes of care (harmful effects of hospitalizations and transitions, including delirium, deconditioning, disability, and to institutionalization thereafter), 4) sarcopenia (age-related atrophy and weakening of skeletal muscle), and 5) the challenge of education, decision making, and behavior changes in the context of declining cognition (especially given the common impairments in executive cognitive function that are associated with CVD and age). Juxtaposed with all these challenges, CR stands out as one of the few standard therapeutic options routinely covered by insurers (including the Centers for Medicare and Medicaid Services [CMS]) that targets improved physical function as a primary outcome, and which thereby has the potential to reduce age-related vulnerabilities to frailty and disability that are commonly exacerbated by CVD.

However, from its inception, older adults have been under-enrolled in CR programs. This is almost paradoxical as the conceptual utility of CR is particularly pertinent to older adults with cardiovascular illness. Aging is associated with increased inflammation,⁷ increased oxidative stress, and other biological changes that predispose to CVD as well as non-cardiac diseases. Prevalence of CVD increases with age, as does the prevalence of diabetes mellitus, chronic obstructive lung disease, chronic kidney disease, arthritis, anemia, mild cognitive impairment, dementia, and other diseases that often occur concurrently with CVD and compound management complexity. Ironically, many of the effects of aging biology and associated disease are conducive to sedentary behaviors that escalate the progression of aggregate vulnerability.⁸ The effects of acute disease and hospitalizations accelerate these risks, with progressive disability associated with each cardiac illness,^9,10 and then to even more downstream risks of recurrent disease, institutionalization, and mortality.

For older CVD patients, almost every aspect of standard CVD care entails aspects of age-related trade-offs. There are numerous examples: benefits of beta-blockers for CHD are counterbalanced by greater age-related vulnerability to chronotropic incompetence, benefits of diuretics for HF are counterbalanced by incontinence, and benefits of anti-hypertensive medications are counter-balanced by increased risks of hypotension and falls. CR provides opportunity of longitudinal assessment to evaluate such issues and refine optimal management strategies.

Similarly, older CVD patients are the most prone to deconditioning, frailty, and disability, such that the implementation of exercise is often the most difficult. Issues of intrinsic muscle weakness, joint instability, and metabolic risks of advanced age are compounded by the high prevalence of comorbidities, medications (sleeping pills, diuretics, etc.), sensory deficits (hearing, vision), and cognitive limits (dementia, executive cognitive decline). Cardiac rehabilitation provides an important opportunity to address these intricacies and to achieve a realistic and safe routine.

Specific Benefits of CR for an Aging Population

Mortality

Multiple studies over decades have focused on aggregate mortality and morbidity benefits of CR.^11-13 Hammill et al. studied 30,161 elderly Medicare patients (average age 74 years) who attended CR for CHD and found that participating in 36 sessions was associated with a 47% lower risk of death over a 5 year follow-up period compared to those who only attended one session.¹⁴ Suaya et al. studied 601,099 Medicare patients and showed that CR benefits to reduce mortality extended across ages and disease severity.¹⁵ Suaya's study utilized three different statistical methods – propensity matching, regression modeling, and instrumental variables – to investigate differences in mortality among CR participants and non-participants.¹⁵ Regardless of the method used, mortality was significantly reduced at one year with progressively greater absolute difference in mortality at five years. Relative reduction in mortality ranged from 43% to 58% at one year and 21% to 33% after 5 years. The benefits were seen across age groups including the very old, and irrespective of comorbidities (including HF) and gender.

Recently studies have also explored benefits of CR in patients with systolic HF. The major landmark randomized controlled HF trial to date is Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training (HF-ACTION), which compared aerobic exercise training to usual care in 2331 systolic HF patients, of whom approximately half were over age 60. The study showed significant reductions in the primary outcome of all-cause mortality or all-cause hospitalizations,¹⁶ but only after accounting adjusting for baseline characteristics strongly predictive of these clinical outcomes. Cochrane reviews of have also demonstrated that exercise training may reduce mortality in HF patients, including those older and frailer than HF-ACTION, with lower mortality demonstrated in studies with follow-up >1 year.^17,18

Exercise Capacity

Exercise capacity becomes increasingly important in older adults because of the typical decline in exercise capacity as part of the aging process, vulnerabilities then exacerbated by acute deconditioning and weakening from disease, medications, and hospitalizations, and associated predisposition to increasing disability and dependency which can be offset in part by CR.^10,19 Older patients who participated in CR have shown improved their cardiorespiratory fitness, peak VO₂, and anaerobic threshold.^20,21

Older CHD patients who participate in CR have also been demonstrated to benefit from increased strength, a gain which is especially important for individuals who are frail or have limited functional status due to the reduction in muscle mass and strength that typically accompanies aging and hospitalizations.²² Mandic et al. found that exercise capacity in elderly individuals after CR was similar to their age-matched healthy counterparts.²³ Participants in CR are able to maximize their exercise capacity, giving them the ability to do daily tasks which enrich their lives. Patients often increase capacities to carry groceries, navigate stairs, and maintain their self-care—critical capabilities for health and independence.

Quality of Life and Symptoms

Studies of CHD patients who participated in CR reported higher quality of life, as well as improved pain, energy level, physical function, well-being, general health, and mental health,²⁴ including those age >70 years compared to younger patients.²¹ These improvements were as significant in older (≥65 years) as in younger subjects. Even when subjects aged ≥75 years were compared to younger patients, the improvements in quality of life and functional status persisted.²⁵ CR can reduce symptoms of dyspnea and palpitations in older patients aged 65-84 years.²⁶ Patients in HF-ACTION trail reported significant benefits in quality of life using the Kansas City Cardiomyopathy Questionnaire (KCCQ) regardless of age and gender.²⁷ Subsequent Cochrane reviews which included older and older and sicker patients than HF-ACTION, also demonstrated improvements in patient-reported quality of life.^17,18

Psychological

The bearing of psychological diseases on CVD is increasingly recognized. In particular, depression has been independently associated with greater CVD morbidity and mortality.^28,29 The association with depression and CHD is complex, but lower physical activity is considered a key mediator.²⁹ A study of CR in patients aged ≥65 years showed that depressed patients had lower levels of exercise capacity and quality of life at baseline compared to non-depressed patients, but improved their exercise capacity similarly and increased their quality of life more than non-depressed patients.³⁰ Patients were also significantly less likely to be depressed after CR.³⁰ More recently, a meta-analysis studied 18 randomized controlled trials to assess the impact of CR on depression in elderly patients using studies with a mean age ≥64 years and demonstrated that exercise therapy combined with psychosocial interventions are more effective in decreasing depression than usual care.³¹

Cognition and Socialization

Cardiac rehabilitation may also help improve cognitive function in older adults. Observational studies have demonstrated that physical activity is associated with a slowing in age-related decline of cognition and reduction in cognitive impairment.^32,33 A cross-sectional study of older adults reported better performance on executive function testing in those individuals who had higher levels of physical activity.³⁴ However, the LIFE (Lifestyle Interventions and Independence for Elders) randomized trial of a 24-month physical activity program in sedentary older adults did not result in any difference in cognitive function.³⁵

Although not all interventions of aerobic and resistance exercise have shown improvement in cognitive performance, multicomponent exercise interventions, which are more representative of CR programs combining aerobic and resistance training together, may be more beneficial to cognitive function than aerobic exercise alone.³⁶ Similarly, CR goals to improve medication regimens, sleep hygiene, diet, and mood likely contribute to improved cognition.

Socialization is also a critical component of CR that may especially benefit older patients. For many, CR serves as a means to counterbalance vulnerabilities to isolation that often arise amidst aging and disease. A study of adults age ≥65 years were surveyed and reported that the socialization aspect of CR was very important and they would even prefer more socialization as part of any CR program.³⁷ Women in particular highlighted the importance of emotional support from attending CR.³⁷

Frailty

Frailty generally involves a state of overall weakening and fatigability, and translates into increased vulnerability to disease and decreased tolerance of therapies.³⁸ Older adults with CVD are particularly prone to frailty and to its detrimental prognostic implications.^39,40 Patients with CVD who are frail have more than twice the morbidity and mortality than similarly aged patients without frailty.⁴⁰ A recent review of interventions for frail elderly patients evaluated 20 studies with exercise interventions including 13 studies of exercise alone.⁴¹ All of the studies were of patients aged ≥65 years and used various exercise prescriptions including both aerobic and resistance training for 3 months up to 2.6 years in one study. Outcomes included different measures of function including the short physical performance battery, activities of daily living, gait speed, strength, and exercise capacity. Exercise training consistently resulted in improved physical performance tests in frail individuals. Patients with CVD were specifically addressed in two studies and observed benefits of exercise.^42,43 In fact, frail patients with CVD are ideally suited for exercise training because of common pathophysiologic links between the two entities such as increased inflammation and insulin resistance.

Older adults with HF are especially susceptible to frailty, and HF hospitalizations often exacerbate these tendencies.⁴⁴ CR programs can be a valuable therapy for patients to regain mobility, strength, and balance. This potential is usually complemented by efforts to optimize medications, nutrition, and other pertinent parameters of care.

Conclusions

Benefits of CR include reduced mortality and morbidity, but also improved exercise capacity, quality of life, symptoms, and mood, parameters that may be particularly important to older CV patients. Cardiac rehabilitation is also particularly useful in addressing idiosyncrasies of advanced age, including atypical symptoms, multimorbidity, polypharmacy, falling risks, learning impairments, and other intricacies of care. Nonetheless, underuse of CR in all ages remains entrenched, particularly among older adults. Future research needs to address these challenges and continue pursuing optimal methods to increase CR enrollment and implementation for older candidates.

References

1. Naughton J, Lategola MT, Shanbour K. A physical rehabilitation program for cardiac patients: a progress report. Am J Med Sci 1966;252:545-53.
2. Balady GJ, Williams MA, Ades PA, et al. Core components of cardiac rehabilitation/secondary prevention programs: 2007 update: a scientific statement from the American Heart Association Exercise, Cardiac Rehabilitation, and Prevention Committee, the Council on Clinical Cardiology; the Councils on Cardiovascular Nursing, Epidemiology and Prevention, and Nutrition, Physical Activity, and Metabolism; and the American Association of Cardiovascular and Pulmonary Rehabilitation. Circulation 2007;115:2675-82.
3. Writing Committee to Develop Clinical Performance Measures for Cardiac Rehabilitation, Thomas RJ, King M, et al. AACVPR/ACCF/AHA 2010 update: performance measures on cardiac rehabilitation for referral to cardiac rehabilitation/secondary prevention services: a report of the American Association of Cardiovascular and Pulmonary Rehabilitation and the American College of Cardiology Foundation/American Heart Association Task Force on Performance Measures. Circulation 2010;122:1342-50.
4. Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2013;62:e147-239.
5. Krumholz HM. Post-hospital syndrome--an acquired, transient condition of generalized risk. N Engl J Med 2013;368:100-2.
6. Graf C. Functional decline in hospitalized older adults. Am J Nurs 2006;106:58-67.
7. Woods JA, Wilund KR, Martin SA, Kistler BM. Exercise, inflammation and aging. Aging Dis 2012;3:130-40.
8. de Rezende LF, REy-Lopez JP, Matsudo VK, do Carmo Luiz O. Sedentary behavior and health outcomes among older adults: a systematic review. BMC Public Health 2014;14:333.
9. Greysen SR, Stijacic Cenzer I, Auerbach AD, Covinsky KE. Functional impairment and hospital readmission in Medicare seniors. JAMA Intern Med 2015;175:559-65.
10. Ferrante LE, Pisani MA, Murphy TE, Gahbauer EA, Leo-Summers LS, Gill TM. Functional trajectories among older persons before and after critical illness. JAMA Intern Med 2015;175:523-9.
11. Lavie CJ, Milani RV. Cardiac rehabilitation and exercise training in secondary coronary heart disease prevention. Prog Cardiovasc Dis 2011;53:397-403.
12. Lawler PR, Filion KB, Eisenberg MJ. Efficacy of exercise-based cardiac rehabilitation post-myocardial infarction: a systematic review and meta-analysis of randomized controlled trials. Am Heart J 2011;162:571-84.
13. Anderson L, Oldridge N, Thompson DR, et al. Exercise-based cardiac rehabilitation for coronary heart disease: Cochrane systematic review and meta-analysis. J Am Coll Cardiol 2016;67:1-12.
14. Hammill BG, Curtis LH, Schulman KA, Whellan DJ. Relationship between cardiac rehabilitation and long-term risks of death and myocardial infarction among elderly Medicare beneficiaries. Circulation 2010;121:63-70.
15. Suaya JA, Stason WB, Ades PA, Normand SL, Shepard DS. Cardiac rehabilitation and survival in older coronary patients. J Am Coll Cardiol 2009;54:25-33.
16. O'Connor CM, Whellan DJ, Lee KL, et al. Efficacy and safety of exercise training in patients with chronic heart failure: HF-ACTION randomized controlled trial. JAMA 2009;301:1439-50.
17. Davies EJ, Moxham T, Rees K, et al. Exercise based rehabilitation for heart failure. Cochrane Database Syst Rev 2010:CD003331.
18. Taylor RS, Sagar VA, Davies EJ, et al. Exercise-based rehabilitation for heart failure. Cochrane Database Syst Rev 2014:CD003331.
19. Cannistra LB, Balady GJ, O'Malley CJ, Weiner DA, Ryan TJ. Comparison of the clinical profile and outcome of women and men in cardiac rehabilitation. Am J Cardiol 1992;69:1274-9.
20. Lavie CJ, Milani RV, Littman AB. Benefits of cardiac rehabilitation and exercise training in secondary coronary prevention in the elderly. J Am Coll Cardiol 1993;22:678-83.
21. Lavie CJ, Milani RV. Disparate effects of improving aerobic exercise capacity and quality of life after cardiac rehabilitation in young and elderly coronary patients. J Cardiopulm Rehabil 2000;20:235-40.
22. Mandic S, Hodge C, Stevens E, et al. Effects of community-based cardiac rehabilitation on body composition and physical function in individuals with stable coronary artery disease: 1.6-year followup. Biomed Res Int 2013;2013:903604.
23. Mandic S, Stevens E, Hodge C, et al. Long-term effects of cardiac rehabilitation in elderly individuals with stable coronary artery disease. Disabil Rehabil 2016;38:837-43.
24. Lavie CJ, Milani RV. Effects of cardiac rehabilitation programs on exercise capacity, coronary risk factors, behavioral characteristics, and quality of life in a large elderly cohort. Am J Cardiol 1995;76:177-9.
25. Lavie CJ, Milani RV. Effects of Cardiac Rehabilitation and Exercise Training Programs in Patients ≥ 75 Years of Age. Am J Cardiol 1996;78:675-7.
26. Stahle A, Mattsson E, Ryden L, Unden A, Nordlander R. Improved physical fitness and quality of life following training of elderly patients after acute coronary events. A 1 year follow-up randomized controlled study. Eur Heart J 1999;20:1475-84.
27. Flynn KE, Pina IL, Whellan DJ, et al. Effects of exercise training on health status in patients with chronic heart failure: HF-ACTION randomized controlled trial. JAMA 2009;301:1451-9.
28. Frasure-Smith N, Lesperance F, Talajic M. Depression following myocardial infarction: impact on 6-month survival. JAMA 1993;270:1819-25.
29. Whooley MA, de Jonge P, Vittinghoff E, et al. Depressive symptoms, health behaviors, and risk of cardiovascular events in patients with coronary heart disease. JAMA 2008;300:2379-88.
30. Milani RV, Lavie CJ. Prevalence and effects of cardiac rehabilitation on depression in the elderly with coronary heart disease. Am J Cardiol 1998;81:1233-6.
31. Gellis ZD, Kang-Yi C. Meta-analysis of the effect of cardiac rehabilitation interventions on depression outcomes in adults 64 years of age and older. Am J Cardiol 2012;110:1219-24.
32. Weuve J, Kang JH, Manson JE, Breteler MM, Ware JH, Grodstein F. Physical activity, including walking, and cognitive function in older women. JAMA 2004;292:1454-61.
33. Abbott RD, White LR, Ross GW, Masaki KH, Curb JD, Petrovitch H. Walking and dementia in physically capable elderly men. JAMA 2004;292:1447-53.
34. Bixby WR, Spalding TW, Haufler AJ, et al. The unique relation of physical activity to executive function in older men and women. Med Sci Sports Exerc 2007;39:1408-16.
35. Sink KM, Espeland MA, Castro CM, et al. Effect of a 24-month physical activity intervention vs health education on cognitive outcomes in sedentary older adults: the LIFE randomized trial. JAMA 2015;314:781-90.
36. Smith PJ, Blumenthal JA, Hoffman BM, et al. Aerobic exercise and neurocognitive performance: a meta-analytic review of randomized controlled trials. Psychosom Med 2010;72:239-52.
37. Dolansky MA, Moore SM, Visovsky C. Older adults' views of cardiac rehabilitation program: is it time to reinvent? J Gerontol Nurs 2006;32:37-44.
38. Fried LP, Tangen CM, Walston J, et al. Frailty in older adults: evidence for a phenotype. J Gerontol A Biol Sci Med Sci 2001;56:M146-56.
39. Singh M, Alexander K, Roger VL, et al. Frailty and its potential relevance to cardiovascular care. Mayo Clin Proc 2008;83:1146-53.
40. Afilalo J, Karunananthan S, Eisenberg MJ, Alexander KP, Bergman H. Role of frailty in patients with cardiovascular disease. Am J Cardiol 2009;103:1616-21.
41. Bibas L, Levi M, Bendayan M, Mullie L, Forman DE, Afilalo J. Therapeutic interventions for frail elderly patients: part I. Published randomized trials. Prog Cardiovasc Dis 2014;57:134-43.
42. Molino-Lova R, Pasquini G, Vannetti F, et al. Effects of a structured physical activity intervention on measures of physical performance in frail elderly patients after cardiac rehabilitation: a pilot study with 1-year follow-up. Intern Emerg Med 2013;8:581-9.
43. Pulignano G, Del Sindaco D, Di Lenarda A, et al. Usefulness of frailty profile for targeting older heart failure patients in disease management programs: a cost-effectiveness, pilot study. J Cardiovasc Med 2010;11:739-47.
44. Murad K, Kitzman DW. Frailty and multiple comorbidities in the elderly patient with heart failure: implications for management. Heart Fail Rev 2012;17:581-8.

Keywords: Acute Disease, Aged, Anaerobic Threshold, Anemia, Antihypertensive Agents, Arthritis, Cardiomyopathies, Comorbidity, Coronary Artery Bypass, Coronary Artery Disease, Dementia, Diabetes Mellitus, Dyspnea, Frail Elderly, Heart Failure, Heart Valve Diseases, Hypotension, Insulin Resistance, Muscle Weakness, Myocardial Infarction, Oxidative Stress, Pulmonary Disease, Chronic Obstructive, Renal Insufficiency, Chronic, Sarcopenia, Secondary Prevention, Sedentary Behavior, Geriatrics

< Back to Listings