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. Author manuscript; available in PMC: 2020 Nov 1.
Published in final edited form as: Clin Geriatr Med. 2019 Jul 2;35(4):407–421. doi: 10.1016/j.cger.2019.07.001

Never Too Old for Cardiac Rehabilitation

Deirdre O’Neill a, Daniel E Forman b,c,*
PMCID: PMC7241425  NIHMSID: NIHMS1583401  PMID: 31543175

THE AGING POPULATION AND ASSOCIATED CARDIOVASCULAR DISEASE

Longevity in the United States has been increasing dramatically since the 1900s, when average life expectancy was approximately 50 years, to the current average life expectancy of close to 80 years.1,2 As a result, by the year 2050, it is estimated that 1 in 4 Americans will be older than 65 years old, with close to 5% of the population being older than 85 years.3,4 This exponential increase in the population of older adults, colloquially termed the “silver tsunami,” presents a challenge to the health care system, as their medical complexities and age-related decline can lead to clinical outcomes that are less well aligned to standards established for younger adults, as well as associated increases in health care utilization and costs.5

Cardiovascular disease (CVD) is a chronic illness for which age is a risk factor. In addition, advancing technology within cardiology and cardiac surgery has contributed to patterns wherein more adults with CVD are surviving into old age, when chronic cardiovascular conditions and associated debility commonly accrue.6 CVD is the most common primary diagnosis at admission to nursing home and the most common cause of death in those older than or equal to 65 years.7 As our population ages, the associated burden of cardiovascular morbidity, mortality, and disability is expected to increase, with associated cost burden and despair. Therefore, an important public health goal is not only increased life expectancy but also preserved functional capacity, well-being, and confidence among older adults with CVD, such that a larger number live well and enjoy preserved independence and life value.8 Cardiac rehabilitation (CR) is a cost-effective intervention that can improve function and quality of life, reducing disability and age-related deconditioning and contributing favorably to improved health outcomes in an aged population.7,9

CARDIAC REHABILITATION

CR is a multidimensional and comprehensive treatment program, typically involving medical evaluation, exercise training, cardiac risk factor modification, and education, aimed to promote lifelong health and wellness in those with CVD.10,11 One of the aims of CR is to help patients transition from hospital, with supervised physical activity to reduce illness-and hospital-associated deconditioning and provide valuable support and education.12 CR programs are individualized to the needs of each patient and provide many benefits to the growing population of older adults with CVD (Table 1).13 Referral to outpatient phase II CR is a class I recommendation from the American Heart Association and American College of Cardiology after myocardial infarction (MI), coronary revascularization, valvular heart surgery, heart or heart-lung transplant, and in stable heart failure with reduced ejection fraction.14 Despite this, literature suggests that only between 13% and 34% of eligible patients attend CR, and older adults, particularly older women, are among the least likely to attend.15,16

Table 1.

Cardiac rehabilitation benefits

Improvement Functional Benefit
Improved exercise capacity Increased ability to perform activities of daily living
Improved strength Increased ability to perform activities of daily living
Increased muscle strength, mass, and power
Reduced sarcopenia
Improved balance Reduced risk of falls
Improved cognition Reduced or delayed cognitive dysfunction
Improved frailty Improved morbidity and mortality
Improved gait velocity
Improved sarcopenia Increased muscle mass, muscle strength, and protein synthesis
Reduced dependence on wheelchairs and walkers
Improved depression Reduced morbidity
Reduced health care utilization
Improved quality of life
Improved self-efficacy Improved self-esteem
Improved quality of life
Improved physical function
Improved socialization Reduced risks associated with social isolation—cognitive decline, negative physical and mental health
Improved emotional support
Improved medication monitoring Reduced polypharmacy and associated adverse drug reactions, falls, mortality
Hemodynamic monitoring and assessment of patient tolerance of medications
Improved medication adherence

IMPROVING THE FUNCTION OF OLDER ADULTS WITH CARDIAC REHABILITATION

Older adults commonly have more numerous accumulated comorbidities and are more vulnerable to becoming sedentary, thus having poorer baseline function and less reserve if hospitalization is to occur. This also results in a higher likelihood of development of disability, dependency, and frailty.16 CR has been shown to improve the function of older adults, enabling individuals to perform activities of daily living at a lower percentage of overall fitness and with a greater self-efficacy.5 Thus, an important opportunity of CR is to expand its application to older adults, enabling more to preserve mobility, independence, and function and to better restore independence after an acute CVD event.17,18

Exercise Capacity

A common primary outcome in CR literature is that of cardiorespiratory fitness (CRF), measured by cardiopulmonary exercise test as peak oxygen uptake (Vo2). It is known that peak Vo2 declines with age, declining by 8% to 10% per decade.19 In younger patients, CRF is primarily determined by cardiovascular and pulmonary components, but with age, other factors influence CRF, including changes in muscle atrophy, the interrelated effects of comorbidity (eg, chronic obstructive pulmonary disease, chronic kidney disease, depression), cognitive impairment, musculoskeletal limitations, deconditioning, and even changes in sensation (vision, hearing, proprioception).16 Although measurements of peak Vo2 may not be as physiologically robust in older adults due to the many factors that influence exercise decline, exercise capacity remains vitally relevant as a fundamental metric of health. Adults with poor CRF are at significantly greater prognostic risk. Moreover, a decline in CRF implies that everyday submaximal activities become relatively more difficult to perform, leading to increasing avoidance of activities that have become tantamount to more work and further exacerbating a cycle of progressive inactivity and functional decline. Sedentary behavior predisposes to disability and dependence that can be particularly aggravated by a CVD illness, especially among those hospitalized and/or after enduring prolonged bed rest. CR is an important intervention to interrupt this vicious cycle of progressive disability.20,21 Thus, the overall clinical benefit of CR in the deconditioned older adult may be even greater than that of a younger patient who has a greater exercise capacity at baseline, because it results in a greater improvement in overall functional capacity and potentially helps to preserve independence.22

Several studies have compared the efficacy of CR in older patients. These studies have consistently shown that older adults derive similar or greater improvements in exercise capacity as younger patients.2325 Balady and colleagues25 studied 778 consecutive patients enrolled in a phase II CR program and categorized them into 3 age groups: younger than 65 years, 65 to 75 years, and older than 75 years. At baseline, exercise tolerance was significantly lower with age. However, after CR, all age groups achieved similar relative improvements in exercise tolerance, with multivariate analysis showing that the greatest change in exercise tolerance was in those with the lowest baseline exercise capacity (<5 metabolic equivalents). This was again demonstrated by Lavie and Milani, who found patients older than or equal to 75 years achieved similar or greater benefits in exercise tolerance compared with those younger than 60 years, with a 39% increase in exercise tolerance in those older than or equal to 75 years, compared with 31% in those younger than 60 years.24 Physical function improved similarly, with an increase by 27% in those older than or equal to 75 years, compared with 20% in those younger than 60 years. Baldasseroni and colleagues26 showed the same trend when they studied 160 patients older than 75 years, after percutaneous coronary intervention, coronary bypass surgery, or valve replacement surgery, and found that CR resulted in clinically relevant improvements in all indices of physical function, with the poorest functioning individuals achieving the greatest relative benefit. Thus, current literature supports the idea that patients with limited physical function (or exercise capacity) can still benefit significantly from CR and that poor baseline function is certainly not a reason for exclusion.

STRENGTH AND BALANCE TRAINING

Whereas improved CRF in younger adults stems primarily form aerobic training, for many older adults who have less muscle mass and greater malnourishment, strengthening is of relatively greater importance. Strength training enhances not only muscle strength and mass but also muscle power and maximal neuromuscular activity in the older adult, at a magnitude similar to that of untrained younger subjects.27 Age-related declines in muscle power output have been shown to be a predictor of functional limitation in older adults; therefore, the improvement in neuromuscular adaptations with strength training is important to maintain the older adults’ ability to perform activities of daily living.27

Balance is rarely a concern for younger adults. However, for many older adults, imbalance is common, affected by muscle weakening, and further exacerbated by vasoactive meds, reduced thirst sensation, neuropathy, and impaired vision. Poor balance is significant in the older adult as it affects gait, thereby potentially compromising independence, and it increases the risk of fall and injury. It is estimated that one in every 3 adults older than or equal to 65 years and close to half of those older than or equal to 80 years suffer at least 1 fall annually.28 Sustaining a fall, even without serious injury, has been shown to result in function decline, poorer self-rated health, and fear of falling that can impair activities of daily living (ADL) ability and negatively affect one’s quality of life.29,30 Low-intensity exercise has been shown to improve postural control and improve maintenance of upright stance, improve balance and lower limb strength, and reduce the incidence of falls.31,32

Barnett and colleagues31 studied 163 adults older than or equal to 65 years, who after screening, were deemed to be at risk of falling. Patients were randomized to an exercise intervention or control. At baseline, groups were similar in terms of physical performance, health, and activity level. The exercise group was found to have a 40% lower rate of falling than that of the control group (relative risk 0.60, 95% confidence interval [CI] 0.36–0.99). Weerdensteyn and colleagues32 studied 113 older adults with a history of falls, finding that exercise decreased falls by 46% (incidence rate ratio 0.54, 95% CI 0.34–0.86) compared with the control group, and balance confidence scores were improved by 6% in the exercise group.

Busch and colleagues33 randomly assigned individuals aged older than or equal to 75 years to usual CR versus CR with additional resistance and balance training intervention. Exercise capacity, strength, and health-related quality of life improved in both groups, but the intervention group had significantly better functional capacity, as measured by 6MWT, TUG, and relative workload; this suggests that CR programs specialized for older adults have the potential to achieve an even greater benefit in this vulnerable population.

Tai Chi has been widely adopted as a form of low-intensity exercise with integrated components of strength, balance, and aerobic training that can be integrated in CR and that may particularly help achieve fall prevention. A study of Tai Chi compared with a 6-month stretching program found that Tai Chi resulted in fewer falls, fewer injurious falls, improved balance, and reduced fear of falling, as compared with those in the stretching group.34 In addition, Lai and colleagues35 have shown that older adults who regularly participated in Tai Chi over a period of 2 years had improvements in CRF, with less decline in their maximal oxygen uptake (Vo2) over the 2 years, compared with their sedentary counterparts.

Therefore, low-intensity exercise has been shown to have a myriad of benefits in the older adult, including balance training, fall reduction, and delay in the decline of CRF with age. Although these benefits are generally presumed to occur with exercise training in younger adults, they need to be addressed more specifically in older adults and in a more individualized manner, based on an individual’s current level of function and their accumulated functional deficits. These deficits can be improved on when strategies targeting specific deficits are integrated into the preexisting CR model, tailoring the program to the individuals’ needs.

COGNITION

Cognitive impairment is common in older adults, with its prevalence increasing with age. The US Preventative Services Task Force estimates that 2.4 to 5.5 million Americans have dementia; 5% of those aged 71 to 79 years, 24% of those aged 80 to 89 years, and 37% of those older than or equal to 90 years. The prevalence of mild cognitive impairment is more difficult to estimate, with stated prevalence of 3% to 42% of those older than or equal to 65 years.36 CVD worsens this burden, with chronic heart failure, coronary artery disease, cerebrovascular disease, and atrial fibrillation all known to be risk factors for cognitive impairment.37,38 There is suggestion that exercise interventions and CR may improve cognitive function in older adults with CVD, potentially lessening this burden.

Lifelong exercise is preferred, but becoming more physically active at any age has been shown to be beneficial to delay or reverse cognitive impairment. The optimal intensity and duration of exercise has not been determined, but generally, higher levels of exercise have been associated with better cognitive outcomes.39 Improvements in multiple cognitive domains, including that of attention, executive function, psychomotor function, and memory were seen after a short 12-week CR program, suggesting global cognitive function may be modified by exercise.40 A systematic review and meta-analysis of 39 randomized controlled trials on exercise interventions in community dwelling adults older than or equal to 50 years found that exercise significantly improved cognitive function (P<.01), with aerobic training, resistance training, multi-component training, and tai chi all having significant point estimates.41 They found that 45 to 60 minutes of at least moderate intensity exercise was most beneficial to cognitive function and that the effect was independent of baseline cognitive status.

FRAILTY

Frailty is a syndrome of decreased reserve and vulnerability to stressors, resulting from cumulative declines across various physiologic systems. There is an increased incidence of frailty in those with CVD, thought potentially to be due to the similar pathophysiologic mechanisms of inflammation.42,43 In addition, frailty is known to accelerate with the onset of CVD and with hospitalization, likely due to rapid loss of muscle mass and strength associated with hospitalization and bed rest.16,44,45 It has been shown that 1% to 5% of muscle strength is lost per day while in hospital and up to one-third of older adults will develop a new disability in ADL with hospitalization, with half of those individuals never retaining the ability to perform that function,46,47 showing the tremendously detrimental effects of hospitalization in older individuals.

Those who are frail have a significantly worse prognosis, with more than twice the morbidity and mortality than age-matched individuals without frailty.48 Oftentimes frail patients are thought to be inappropriate for physical rehabilitation. However, in the last decade, an increasing number of frail patients have been enrolled in CR, further increased by cardiac innovations such as transcatheter aortic valve replacement. Despite this, there still remains a large gap in the literature on the CR of frail individuals.

There is a growing body of evidence suggesting exercise in itself is effective in improving or reversing frailty, even in the frailest population. In a seminal study, Fiatarone and colleagues49 published a randomized controlled trial randomizing 100 frail nursing home residents, mean age 87 years, to a progressive resistance exercise training program, multinutrient supplementation, both or neither intervention, over a 10-week period. They found those randomized to an exercise intervention had increased muscle strength, gait velocity, stair climbing power, and cross-sectional thigh muscle area, as compared with those who did not exercise, showing that even in oldest old, frail, nursing home residents, a short 10-week exercise program can result in significant improvement in physical function and frailty. Another study randomized 115 older adults, mean age 83 years, with mild to moderate frailty, to a low-intensity flexibility-focused home exercise program or a progressive exercise training program. The exercise training group improved significantly in 3 of 4 measures of physical function, showing that intensive exercise training can improve physical function in the oldest old patients with baseline frailty and disability.50 Therefore, although the literature supporting CR in frailty is limited, exercise interventions are some of the only consistently supported interventions affecting frailty in literature today. Furthermore, the utility of associated nutritional enhancement, particularly protein supplementation for patients with muscle atrophy, remains a dynamic area of investigation.51

SARCOPENIA

Sarcopenia is defined as the age-related loss of muscle mass, strength, and function.52 Evidence has shown that older adults lose approximately 0.5% of their total skeletal muscle mass per day and 0.3% to 4.2% of their muscle strength per day.53 Furthermore, sarcopenic loss of muscle strength progresses independently of muscle atrophy. The cause is multifactorial, often related to reduced exercise, insufficient dietary intake, reduction in type II skeletal muscle fibers, and reduction of insulin-like growth factor 1.54 Muscle strength is an important determinant of overall function (aerobic and balance), particularly in older adults, with low muscle strength being predicting future functional decline and higher incidence of disability and mortality.55,56

Exercise has been shown to prevent and treat sarcopenia—increasing muscle mass, muscle strength, and protein synthesis.54 This may be best done with resistance training. A study by Chen and colleagues54 randomly assigned older adults aged 65 to 75 years with sarcopenic obesity to resistance training, aerobic training, combination training, or no intervention, over an 8-week period. Muscle strength was found to be higher in the resistance training group compared with all other groups at 8 and 12 weeks. Resistance training was compared with control intervention of yoga or breathing exercises in women older than or equal to 65 year with CVD, finding that a 6-month resistance training program resulted in statistically significant improvement in physical work capacity, balance coordination, and 6MWT performance, when compared with the control intervention.57 Even very old patients with poorer baseline function can benefit from strength training, with Fiatarone and colleagues58 showing that introducing a strength training program in institutionalized octogenarians and nonagenarians can increase strength by 100% after several weeks, with many individuals being able to reduce their dependence on wheelchairs and walkers. Therefore, resistance training can help prevent and treat sarcopenia as well as promote beneficial effects in strength and endurance, enhancing each individual’s ability to perform ADLs.

QUALITY OF LIFE

The literature on CR suggests benefit not only in terms of hard outcomes, such as morbidity and mortality, but also in outcome measures such as quality of life, which are equally, if not more, important to older patients. Lavie and Milani compared adults aged 70 years and older with patients younger than 55 years, participating in CR. The older patients had significant improvement in quality of life scores, with improvements even greater than that of younger patients (20% vs 15%, P = .03).23 Another study by Lavie and Milani found quality of life, pain, energy, physical function, well-being, general health, and mental health scores were all significantly improved in cardiac patients who participated in CR and that this improvement was as significant in patients older than or equal to 65 years as it was in younger individuals.24

DEPRESSION

Depression is prevalent in older adults, with an estimated 34 million Americans older than or equal to 65 years suffering from depression.59 It is also prevalent in patients with CVD, with estimates that depression in those with CVD occurs 2 to 3 times more often than in the general public.60 Recognizing and treating depression in CVD is important, as its presence has been shown to result in a greater than 4-fold increase in death post-MI, as well as increased health care utilization and decreased perceived quality of life.61,62 In addition, treatment of depression can lead to improved physical function, with Callahan and colleagues63 showing that older patients with depression randomized to a collaborative treatment intervention for depression not only had improved depression but experienced significantly better physical function at 1 year than those patients receiving usual care.

CR has been reported to improve the prevalence of and symptoms of depression by 50% to 70%, similar to that of antidepressant medications.18 Milani and Lavie18 studied 522 consecutive patients with CVD enrolled in CR, with a mean age of 64 years. They found that the prevalence of depression decreased 63% after CR completion, from 17% to 6% (P<.0001). Those who remained depressed after CR had a greater than 4-fold higher mortality than those who were no longer depressed (22% vs 5%, P = .0004). In addition, those who were depressed but completed CR had a 73% lower mortality than control patients who were depressed and did not complete a rehabilitation program (8% vs 30%, P = .0005). Even mild improvements in fitness level were associated with decreased depression and mortality reduction. Milani and colleagues64 also investigated 189 patients with stage C heart failure, mean left ventricular ejection fraction of 35%, enrolled in CR, following them for a mean of 5 years. The prevalence of depression decreased by 40% after CR, from 22% to 13%, P<.0001. Again, those who remained depressed despite CR had close to a 4-fold increased mortality compared with those whose depression resolved post-CR (43% vs 11%, P = .005), and those who remained depressed but completed CR had lower mortality than those who were depressed and dropped out of CR (44% vs 11%, P<.05).

A meta-analysis of 18 randomized controlled trials assessed the effect of CR on depression in older adults, aged more than 64 years. They found that exercise therapy combined with psychological interventions was more effective in decreasing depression than usual care.65 Therefore, the addition of cognitive behavioral therapy to the current multidisciplinary CR program may improve both depression and mortality in individuals with depression, and a reduction in depression can improve physical function and quality of life in these patients.

SELF-EFFICACY

Self-efficacy is defined by Bandura as a “patient’s belief that they have the ability to influence their lives via self-imposed actions.”66 Higher self-efficacy has been related to higher self-esteem, increased quality of life, increased ADL participation, reduced depression and anxiety, and better disease management.16,67 Research suggests that physical exercise is beneficial to positive self-efficacy. A randomized controlled trial of 174 older adults, aged 60 to 75 years, compared a 12-month exercise program with a stretching/toning control program. There were significant increases in all levels of self-esteem in the intervention group.68 Another trial included more than 400 older adults, ages 70 to 89 years, who were deemed to be at elevated risk for disability and randomized them to a physical activity intervention or a successful aging educational control group for 12 months. The physical activity group had more favorable changes in self-efficacy and physical functioning than those in the control group, even in this group of very old adults with baseline impairment in function.69

SOCIALIZATION

Social isolation is widespread in older adults, with estimates that one-third to one-half of the older adult population experience social isolation and loneliness.70 Social isolation is known to have a negative impact on physical and mental health, is associated with cognitive decline and dementia, and has been identified as a risk factor for all-cause morbidity and mortality.7072 In addition, socialization with patients who have similar disease processes and are at various stages in recovery and CR is thought to be beneficial, especially to older patients who are at higher risk of social isolation. A survey of older adults aged 65 years or more found that the socialization aspect of CR was very important and they would prefer to have an even larger socialization component,73 suggesting CR serves as a means to counteract yet another vulnerability in older adults.

POLYPHARMACY

Polypharmacy is the use of numerous drugs by a single individual, commonly defined in the literature as greater than or equal to 5 medications.74 It is common in older adults, who often have multimorbidity and is associated with adverse outcomes such as increased mortality, falls, and adverse drug reactions.74 Population-based survey and cross-sectional study results have suggested that polypharmacy affects 40% to 50% of older adults.75 It has been suggested that certain medications may be detrimental to physical activity and rehabilitation in older adults.76 Thus, CR can provide a unique opportunity to review medications in all participants, particularly older adults, potentially reducing polypharmacy. In addition, for older patients with cardiac disease, many beneficial medications are counterbalanced by age-related compromises, such as incontinence with diuretics and hypotension and falls with beta blockers.5 CR allows a longitudinal hemodynamic monitoring and assessment of individual patient tolerance of medications. This can ensure that cardiovascular management is well-coordinated and more patient-centered.

In addition to addressing polypharmacy and assessing individual patients’ tolerance of mediations, CR has also been shown to be beneficial in terms of patient medication adherence. It is known that up to 50% of patients will stop medications for chronic conditions such as diabetes, hypertension, and dyslipidemia in the first year.77 CR may also promote medication adherence, by providing education and access to health care professionals to which patients can direct medication-related inquiries. The ACTION-Registry-GWTG was used to study close to 12,000 adults, older than or equal to 65 years, participating in CR after MI.78 It was found that participation in an increased number of CR sessions was associated with improved adherence to secondary prevention medications and each 5-session increase in participation was associated with both lower mortality (adjusted hazard ratio [HR] 0.87, 95% CI 0.83–0.92) and lower risk of major adverse cardiac events (adjusted HR 0.69, 95% CI 0.65–0.73). Therefore, medication management is another valuable and often under-valued service provided through CR.

BARRIERS TO CARDIAC REHABILITATION IN OLDER ADULTS

Despite the evidence described earlier, participation in CR is poor, with overall participation rate of less than 30%.11 Suaya and colleagues79 found that of Medicare beneficiaries older than or equal to 65 years, CR was only used in 13.9% of those after MI and 31% of those after coronary bypass surgery. Literature suggests older adults are 1.5 to 2 times less likely to participate in CR compared with younger adults,22 with participation rate of only 13% in those older than or equal to 80 years ,79 discouraging in light of evidence supporting its use.

Lack of referral to CR is a multifactorial, with physician recommendation playing a key role.80 Firstly, a physician’s lack of knowledge of programs in the area and of the potential benefits of CR can lead to lower referral rates. Patients under the care of a cardiologist or cardiac surgeon are more likely to participate in CR compared with those cared for by a primary care physician, potentially because of a greater knowledge of the presence and benefits of CR.81 Secondly, some physicians believe lifestyle interventions are of less benefit in older adults, as life expectancy is limited.44,82 However, an average 65-year-old has an anticipated life expectancy of 15 to 17 years, remaining functionally independent for two-thirds of this time. People aged 75 and 85 years have an average life expectancy of 10 to 11 years and 6 years, respectively and will remain independent for one-half of this time.22,83

Thirdly, physicians are concerned about the safety of CR in older adults.44,82 There is a risk of cardiac complications with CR; however, this risk is low, with a statement from the American Heart Association regarding the risk of cardiovascular events during CR, estimating the risk of death, cardiac arrest, or MI as 1/60,000 to 80,000 hours of exercise.84 There is no reported higher incidence of cardiac events among older adults undergoing CR compared with the general population.23,64,85 There is also a concern regarding older patients sustaining a fall during CR; however, this is inconsistent with the literature, which shows exercise reduces the risk of fall-related injuries.30,86 Nonetheless, it is prudent to take additional precautions when older adults are participating in CR, including longer warm-ups to improve flexibility and blood flow to large muscle groups and longer cool-down periods, to allow for exercise-related vasodilation to recover, reducing the risk of postexercise hypotension.5

Lastly, it is thought that physicians do not refer due to the lack of well-conducted, high-quality studies on CR in older adults.44,82 Much of what is currently published is observational or substudies of randomized controlled trials. In addition, there is lack of evidence on participation and outcome of patients with heart failure with preserved ejection fraction in CR, one of the most common cardiac diagnoses in the older population. There is a desperate need for the development of novel interdisciplinary CR programs, developed by geriatricians and cardiologists, to improve the utility for older adults. This should focus on issues important to older adults, such as improving coordination, balance, and physical and cognitive functioning, in order to improve the older adult’s ability to perform ADLs independently and retain independence. There is also a great need for high-quality research on CR in older adults and broad dissemination of this research, in order to reassure physicians and patients of the safety and benefits of participation in CR.

In addition, patient-related factors influence the lack of participation of older adults in CR. They often no longer drive, making transportation to facility-based programs difficult.87,88 Older adults, particularly women, are often caregivers for sick spouses, thus they are unable to easily participate in activities outside of the home. Older individuals often have more numerous medical comorbidities, contributing to their becoming more sedentary, and this can result in anxiety about their ability to participate. Home-based CR aims to bridge the gap between patients who are interested in participating in CR but are limited by logistics. There has been a proliferation of literature on home-based CR within the past few years, providing data on beneficial outcomes and safety of this method of CR, with suggestion that it may provide longer lasting physical function benefits, as it teaches patients skills they can use in the long term, potentially creating a more permanent change in lifestyle than hospital-based CR.89 However, the safety and efficacy of home-based CR has not been assessed in the oldest, most frail individuals. A trial recently initiated by National Institute of Aging, Modified Approach to CR in Older adults (MACRO), will further investigate hybrid- and home-based CR models in older adults (ClinicalTrials.gov Identifier: NCT03922529). CR will be tailored to the individual’s needs throughout, using hybrid-and home-based options to best meet these challenges. This study will pioneer novel CR approaches for vulnerable older adults.

SUMMARY

In conclusion, cardiac disease is extremely prevalent in older adults, a population that is expanding rapidly. Age-related decline and multimorbidity can lead to decreased function, further exacerbated by cardiac disease and hospitalization. CR provides an effective means of reintroducing these patients to exercise in a safe and monitored setting, where they can regain confidence and physical ability that can allow them to continue to function and live independently for as long as possible. In addition, CR provides an opportunity to treat other geriatric-specific issues that commonly arise in this population, such as deconditioning, frailty, balance retraining and fall reduction, sarcopenia, polypharmacy, depression, and cognitive decline. Despite these important functional improvements with CR, older adults remain one of the most infrequently enrolled. This is multifactorial, but largely led by the fact that there is a need for the development of novel CR programs individualized to this population and a lack of high-quality literature supporting outcomes in older adults, both of which could improve physician referral patterns and patient participation in CR in future.

KEY POINTS.

  • Cardiovascular disease is a chronic illness for which age is a risk factor.

  • As our population ages, the associated burden of cardiovascular morbidity, mortality, and disability is expected to increase, with associated cost burden and despair.

  • Cardiac rehabilitation is a cost-effective intervention that can improve function and quality of life, reducing disability and age-related deconditioning and contributing favorably to improved health outcomes in an aged population.

Acknowledgments

Funding: Dr D.E. Forman is supported by NIA R01 AG060499-01, R01AG058883, R01AG053952, P30AG024827 and NIH UO1AR071130.

Footnotes

Disclosure: The authors have nothing to disclose.

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