Determinants of exercise tolerance after acute myocardial infarction in older persons

Beyond MACE: a multidimensional approach to outcomes in clinical trials for older adults with stable ischemic heart disease

The global population of older adults is expanding rapidly resulting in a shift towards managing multiple chronic diseases that coexist and may be exacerbated by cardiovascular illness. Stable ischemic heart disease (SIHD) is a predominant contributor to morbidity and mortality in the older adult population. Although results from clinical trials demonstrate that chronological age is a predictor of poor health outcomes, the current management approach remains suboptimal due to insufficient representation of older adults in randomized trials and the inadequate consideration for the interaction between biological aging, concurrent geriatric syndromes, and patient preferences. A shift towards a more patient-centered approach is necessary for appropriately and effectively managing SIHD in the older adult population. In this review, we aim to demonstrate the distinctive needs of older adults who prioritize holistic health outcomes like functional capacity, cognitive abilities, mental health, and quality of life alongside the prevention of major adverse cardiovascular outcomes reported in cardiovascular clinical trials. An individualized, patient-centered approach that involves shared decision-making regarding outcome prioritization is needed when any treatment strategy is being considered. By prioritizing patients and addressing their unique needs for successful aging, we can provide more effective care to a patient population that exhibits the highest cardiovascular risks.

Factors contributing to exercise tolerance in patients with coronary artery disease undergoing percutaneous coronary intervention

BACKGROUND

Exercise tolerance plays a vital role in the process of cardiac rehabilitation in patients undergoing percutaneous coronary intervention (PCI). The study sought to determine the characteristics, risks and correlates of post-PCI exercise tolerance in patients with coronary artery disease (CAD).

METHODS

We analyzed clinical data of 299 CAD patients undergoing elective PCI and completing cardiopulmonary exercise testing (CPET). According to the Weber classification, post-PCI exercise tolerance was evaluated by peak oxygen uptake (VO₂ peak). We assessed the impact of 34 predefined clinical features, cardiac functional parameters, and blood biochemistry data on exercise tolerance by univariate analysis and logistics regression analysis.

RESULTS

Of 299 patients, 74.92% were men and average age was 60.90 ± 10.68 years. VO₂ peak in the entire population was 17.54 ± 3.38 ml/kg/min, and 24.41% (n = 73) were less than 16 ml/kg/min, who were considered to have exercise intolerance. Multivariate logistics regression results showed that sex, diabetes mellitus, number of stents, left atrial diameter (LAD), end-diastolic volume (EDV), and hemoglobin influenced the peak oxygen uptake of CAD patients undergoing elective PCI. (All p < 0.05).

CONCLUSIONS

Nearly one quarter of CAD patients have exercise intolerance in the early post-PCI period. Female, diabetes mellitus, number of stents, LAD, EDV might negatively impacted post-PCI exercise tolerance, which need further warrant by large scale cohort study.

Depression anticipates patients at risk of poor exercise stress test performance after percutaneous coronary angioplasty: A short-term longitudinal study

AIMS

The exercise stress test is commonly used to assess physical capacity and recovery in coronary artery disease (CAD) patients after percutaneous transluminal coronary angioplasty (PTCA). Despite depressive symptoms have been consistently associated with adverse outcomes in CAD patients, they are rarely considered as risk factors of poor exercise test. The present study investigated the influence of depressive symptoms, along with anxiety, sleep problems and perceived health on exercise test in PTCA patients.

METHODS

One hundred and sixty-five patients who underwent PTCA completed the Beck Depression Inventory-II (BDI-II), the Beck Anxiety Inventory, the Sleep Condition Index and the 12-item Short-Form Health Survey and, after 20 days, underwent exercise stress test.

RESULTS

Higher BDI-II scores significantly predicted lower maximal workload measured in metabolic equivalents (METs; β = -0.13; p = .030), shorter total exercise duration (β = -5.23; p = .034) and the inability to reach maximum heart rate during exercise test (OR = 1.07; p = .032), even after controlling for relevant sociodemographic and biomedical risk factors.

CONCLUSIONS

Depressive symptoms specifically predicted worse exercise stress test performance in patients after PTCA, controlling for common risk factors. Focusing on the assessment of depressive symptoms, in addition to sociodemographic and biomedical risk factors, is essential to anticipate patients at risk of poor physical capacity after PTCA.

The Beneficial Role of Exercise Training for Myocardial Infarction Treatment in Elderly

Worldwide, elderly people have a higher prevalence of myocardial infarction (MI), which is associated with body function aging and a sedentary lifestyle. In addition to medication, exercise training is a well-established supplementary method to prevent and treat cardiovascular diseases (CVDs). Substantial evidence has shown the value of different intensity exercise programs in the prevention and treatment of MI, and exercise rehabilitation programs are also applicable to elderly patients with MI. Although exercise rehabilitation programs could significantly improve function, quality of life (QoL), and lower mortality and morbidity for people with MI, such programs are underused because their mechanisms are not accurately elucidated. To promote the application of exercise therapy for MI, this review summarizes the benefits and mechanisms of exercise rehabilitation for post-MI patients and provides rationalized proposals for outpatient cardiac rehabilitation.

Association Between Depressive Symptoms and Exercise Capacity in Patients With Heart Disease: A META-ANALYSIS

PURPOSE

Depression and reduced exercise capacity are risk factors for poor prognosis in patients with heart disease, but the relationship between the 2 is unclear. We assessed the relationship between depressive symptoms and exercise capacity in patients with heart disease.

METHODS

PubMed, Cochrane Library, Google Scholar, and ProQuest databases were browsed for English-language studies published from January 2000 to September 2013. Studies including adult patients with coronary artery disease, heart failure, congenital heart disease, and implantable cardioverter defibrillator, reporting correlation between a depression scale and exercise capacity ((Equation is included in full-text article.)O2peak, peak watts, estimated metabolic equivalents, and incremental shuttle walk test distance), as well as studies from which such a correlation could be calculated and provided by the authors, were included. Correlation coefficients (CCs) were converted to Fischer z values, and the analysis was performed using a random-effects model. Then, summary effects and 95% CIs were converted back to CCs.

RESULTS

Fifty-nine studies (25 733 participants) were included. Depressive symptoms were inversely correlated to exercise capacity (CC = -0.15; 95% CI, -0.17 to -0.12). Heterogeneity was significant (I = 64%; P < .001). There was no evidence of publication bias (Fail-safe N = 4681; Egger test: P = .06; Kendall test: P = .29).

CONCLUSIONS

Patients with heart disease and elevated depressive symptoms may tend to have reduced exercise capacity, and vice versa. This finding has clinical and prognostic implications. It also encourages research on the effects of improving depression on exercise capacity, and vice versa. The effects of potential moderators need to be explored.

A systematic review of community-based health interventions on depression for older adults with heart disease

PURPOSE

This systematic review examined the effectiveness of community-based heart-health interventions on depression outcomes among homebound elderly (64 years and older) with heart disease.

DESIGN AND METHODS

A comprehensive literature search and meta analysis was performed to evaluate randomized controlled trials examining outpatient or home-based interventions. Methodological quality was assessed by standard criteria developed by the Cochrane Collaborative Initiative.

RESULTS

Fifteen studies met our inclusion criteria and all measured depression outcomes. Studies differed in scope and methodological rigor and sample sizes varied widely. Problems in treatment fidelity and masking of group assignment were noted. Great variability was found in depression outcomes due to the differences in methodology and intervention. Five studies reported significant treatment effect on depression; three of those employed home-based interventions and two were outpatient-clinic interventions. Ten studies were included in the meta analysis and the effect sizes (ESs) ranged from -0.39 (in favor of control group) to 0.65 (in favor of treatment group). The mean weighted ES was 0.11 and six studies showed positive ESs.

IMPLICATIONS

Mixed evidence for community-based heart disease interventions on depression outcomes was found. Future research should include sub-analysis of ESs of interventions on depression outcomes by different demographic characteristics of the study sample, common depression outcome measures, and different follow-up periods.

Exercise-based cardiac rehabilitation for very old patients (> or =75 years): focus on physical function

Older patients have high rates of physical function impairment and disability following a cardiac event. Exercise training has been shown to favorably affect such limitations, as well as cardiovascular risk factors, symptoms, and mortality post coronary event in middle-aged patients. Aerobic capacity, body strength, quality of life, and physical function are improved with exercise-based cardiac rehabilitation (CR) in patients older than 65 years. However, there have been relatively few studies of the effects of exercise-based CR on physical function recovery in the very old patients (> or =75 years), despite the continuous growth of this segment of the population. After hospitalization for a cardiac event, postacute inpatient CR serves as a bridge between acute care and independent home living for the most disabled older patients. It plays an important role in the physical recovery process, particularly after cardiac surgery. Exercise-based outpatient (phase II) CR, starting early after hospital discharge, is safe in very old patients and studies demonstrate that these patients derive similar benefits from CR, compared with younger patients, regarding physical function improvement. Older patients, however, are less likely than younger cardiac patients to participate in outpatient CR programs. There is a need to find protocols that could increase the referral and participation rates of the frailer and older cardiac patient to exercise-based CR.

Relationships between fatigue and early postoperative recovery outcomes over time in elderly patients undergoing coronary artery bypass graft surgery

BACKGROUND

Despite successful coronary artery bypass graft (CABG) surgery, some patients continue to experience fatigue after their surgery.

OBJECTIVE

The purpose of this secondary analysis study was to examine the relationships of fatigue and early recovery outcomes (psychosocial and physiologic functioning, and physical activity) over time (6 weeks and 3 months) among older adult subjects, age 65 years and older, after CABG surgery. Comparison groups were those subjects who had fatigue at 3 weeks after surgery and nonfatigued subjects.

DESIGN

A prospective, comparative design was used for this secondary analysis study.

SAMPLE

Subjects in this study were drawn from the control group of subjects enrolled in the larger parent study. Subjects (N = 119) were dichotomized into fatigue (n = 66) and nonfatigued (n = 53) groups on the basis of their 3-week self-reports of postoperative fatigue.

RESULTS

At 6 weeks after surgery, fatigued subjects had significantly (P < .05) more impaired psychosocial functioning (role-emotional [t = 1.9], social [t = 2.6], and mental [t = 1.9] functioning) on the basis of the Medical Outcome Study Short Form 36. They had significantly (P < .005) higher mean hospital anxiety (t = -3.6) and depression (t = -2.9) subscale scores, respectively. Anxiety (t = -2.3, P < .05) remained significantly (P < .05) impaired at 3 months. At 6 weeks, role physical functioning, measured by the Medical Outcome Study Short Form 36, was significantly impaired (t = 2.4, P < .01). There were no significant differences in physical activity variables as measured by an RT3 accelerometer (Stayhealthy, Inc., Monrovia, CA) and self-report diary.

CONCLUSIONS

Persistent fatigue can hamper early recovery after CABG surgery. Tailored interventions are needed to address fatigue management and improve patient outcomes.

Evidence-Based Recommendations for Cancer Fatigue, Anorexia, Depression, and Dyspnea

Purpose

The experience of patients with cancer often involves symptoms of fatigue, anorexia, depression, and dyspnea.

Methods

We developed a set of standards through an iterative process of structured literature review and development and refinement of topic areas and standards and subjected recommendations to rating by a multidisciplinary expert panel.

Results

For fatigue, providers should screen patients at the initial visit, for newly identified advanced cancer, and at chemotherapy visits; assess for depression and insomnia in newly identified fatigue; and follow up after treatment for fatigue or a secondary cause. For anorexia, providers should screen at the initial visit for cancer affecting the oropharynx or gastrointestinal tract or advanced cancer, evaluate for associated symptoms, treat underlying causes, provide nutritional counseling for patients undergoing treatment that may affect nutritional intake, and follow up patients given appetite stimulants. For depression, providers should screen newly diagnosed patients, those started on chemotherapy or radiotherapy, those with newly identified advanced disease, and those expressing a desire for hastened death; document a treatment plan in diagnosed patients; and follow up response after treatment. For general dyspnea, providers should evaluate for causes of new or worsening dyspnea, treat or symptomatically manage underlying causes, follow up to evaluate treatment effectiveness, and offer opioids in advanced cancer when other treatments are unsuccessful. For dyspnea and malignant pleural effusions, providers should offer thoracentesis, follow up after thoracentesis, and offer pleurodesis or a drainage procedure for patients with reaccumulation and dyspnea.

Conclusion

These standards provide a framework for evidence-based screening, assessment, treatment, and follow-up for cancer-associated symptoms.

The use of aerobic exercise training in improving aerobic capacity in individuals with stroke: a meta-analysis

OBJECTIVE

To determine whether aerobic exercise improves aerobic capacity in individuals with stroke.

DESIGN

A systematic review of randomized controlled trials. DATABASES SEARCHED: MEDLINE, CINAHL, EMBASE, Cochrane Database of Systematic Reviews and Physiotherapy Evidence Database were searched.

INCLUSION CRITERIA

Design: randomized controlled trials (RCTs).

PARTICIPANTS

individuals with stroke.

INTERVENTIONS

aerobic exercise training aimed at improving aerobic capacity.

OUTCOMES

PRIMARY OUTCOMES

aerobic capacity (peak oxygen consumption (VO2), peak workload).

SECONDARY OUTCOMES

walking velocity, walking endurance.

DATA ANALYSIS

The methodological quality was assessed by the PEDro scale. Meta-analyses were performed for all primary and secondary outcomes.

RESULTS

Nine articles (seven RCTs) were identified. The exercise intensity ranged from 50% to 80% heart rate reserve. Exercise duration was 20-40 min for 3-5 days a week. The total number of subjects included in the studies was 480. All studies reported positive effects on aerobic capacity, regardless of the stage of stroke recovery. Meta-analysis revealed a significant homogeneous standardized effect size (SES) in favour of aerobic exercise to improve peak VO2 (SES 0.42; 95% confidence interval (CI) 0.15-0.69; P=0.001) and peak workload (SES 0.50; 95% CI 0.26-0.73; P<0.001). There was also a significant homogeneous SES in favour of aerobic training to improve walking velocity (SES 0.26; 95% CI 0.05-0.48; P= 0.008) and walking endurance (SES 0.30; 95% CI 0.06-0.55; P= 0.008).

CONCLUSIONS

There is good evidence that aerobic exercise is beneficial for improving aerobic capacity in people with mild and moderate stroke. Aerobic exercise should be an important component of stroke rehabilitation.

Measuring health-related quality of life in older patient populations: a review of current approaches

The changing demographic profile of the world's population towards old age and evidence of people living for longer with less time spent in ill health highlight the importance of addressing quality-of-life (QOL) assessment issues for older people. The assessment of health-related QOL (HR-QOL) has received considerable attention in the last 2-3 decades, with a wide variety of assessment instruments available. These instruments can be either generic or disease specific, health profiles or preference based. The literature was reviewed systematically to identify studies measuring HR-QOL in older patient groups. A total of 37 studies were identified, 11 of which were randomised, controlled trials/evaluations, 14 were prospective studies that did not involve a randomised, controlled intervention, and 12 were cross-sectional studies. Studies were summarised in terms of the study aim, patient population characteristics, the instrument used to measure HR-QOL, and HR-QOL findings. A majority of studies used a generic HR-QOL instrument, the single most commonly used being the 36-Item Short-Form Health Survey. In many cases, a second disease-specific measure was used in combination with the generic measure. In a majority of studies involving interventions, significant improvements in HR-QOL were noted. In prospective studies, a negative impact of health conditions (e.g. myocardial infarction and chronic heart failure) was also identified using HR-QOL assessments. None of the studies in this review used HR-QOL measurement instruments that were old-age specific. Using instruments that are not specific to a particular age group enables comparisons to be made with other age groups, i.e. younger or middle-aged groups. However, the questionnaire items of HR-QOL instruments tend to be phrased predominantly in relation to physical function and thus may inadvertently discriminate against older persons, whose physical function is likely to be not as good as that of younger people. Particular issues in the assessment of HR-QOL in older patient populations include the persistent finding of a poor relationship between QOL and disability/disease severity, the dynamic nature of QOL, and the importance of valid proxy ratings for those unable to make decisions or communicate for themselves. It is important, therefore, that assessment of HR-QOL incorporates issues of importance to individual older people by broadening the scope of the measurement instruments, thus representing more validly the HR-QOL status of older patient groups. Future research in HR-QOL must incorporate the perspective of the individual in order to enable valid conclusions to be derived based on content that is relevant to the individual being assessed, thus informing management decisions, policy and practice more meaningfully.

Assessment of Quality of Life With 5 Different Scales in Patients Participating in Comprehensive Cardiac Rehabilitation After Acute Myocardial Infarction

BACKGROUND

Measures assessing quality of life (QOL) in patients participating in comprehensive cardiac rehabilitation (CCR) have not been established in Japan.

METHODS AND RESULTS

To compare different types of QOL scales and to determine the impact of CCR on QOL in Japanese cardiac patients, 5 different types of questionnaires were assessed in 44 patients participating in CCR after acute myocardial infarction (AMI). After 3-month CCR, peak oxygen uptake (PVO2, p<0.01), Sickness Impact Profile (SIP) total score (p<0.05) and physical function-related QOL scores (Specific Activity Scale (SAS), p<0.01; SIP physical score, p<0.01) significantly improved, whereas psychosocial/mental aspect-related QOL scores (Ministry of Health and Welfare (MHW)-QOL score, SIP psychosocial score, State-Trait Anxiety Inventory, Self-rating Depression Scale) did not change on the average. However, patients with low PVO2 (<21.7 ml.min-1.kg-1) showed significant improvements in all scores after CCR, whereas patients with preserved exercise capacity showed improvements only in physical function-related scores (SAS and physical SIP). Furthermore, patients with anxiety and depression showed significant improvements in these respective measures after CCR.

CONCLUSION

In patients with AMI, physical function-related QOL scores improve after a 3-month CCR program, but psychosocial/mental aspect-related QOL scores improve only in those with impaired exercise tolerance or anxiety/depression. Thus, changes in QOL after CCR depend on type of QOL scale used and the baseline status of the patient. In addition, in Japanese cardiac patients MHW-QOL mainly reflects psychosocial/mental aspect-related QOL, as well as overall QOL.

Fatigue and physical activity in older women after myocardial infarction

BACKGROUND

Within 6 years of a myocardial infarction (MI) more women (35%) than men (18%) will have another MI. Participation in physical activity is one of the most effective methods to reduce cardiac risks; however, few older women participate. One of the most frequently reported barriers to physical activity is fatigue.

OBJECTIVES

The specific aims of this study were to (1) describe factors related to fatigue in older women after MI and (2) examine the relationship of fatigue to physical activity in older women after MI.

METHODS

This descriptive correlational study examined the effects of age, body mass index, comorbidities, sleep, beta-blocker medication, depression, and social support on fatigue and physical activity in women (N = 84), ages 65 to 88 years old, 6 to 12 months post-MI. All women had their height and weight measured and completed (1) a health form on comorbidities, physical activity, and medication history; (2) the Geriatric Depression Scale; (3) the Epworth Sleepiness Scale; (4) the Revised Piper Fatigue Scale; and (5) the Social Provisions Scale.

RESULTS

The majority (67%) of the women reported fatigue that they perceived as different from fatigue before their MI. Moderately strong correlations were noted among depression, sleep, and fatigue, and multivariate analysis indicated that depression and sleep significantly accounted for 32.7% of the variance in fatigue. Although only 61% of the women reported participating in physical activity for exercise, most were meeting minimal kilocalories per week for secondary prevention. Fatigue was not significantly associated with participation in physical activity.

CONCLUSION

Describing correlates to fatigue and older women's participation in physical activity after MI are important to develop interventions targeted at increasing women's participation in physical activity, thus decreasing their risk for recurrent MIs.

Are exercise stress tests appropriate for assessing myocardial ischemia in patients with major depressive disorder?

BACKGROUND

Major depressive disorder (MDD) disproportionately affects patients with coronary artery disease (CAD). Evidence of myocardial ischemia with electrocardiography (ECG) or single-photon-emission-computed-tomography (SPECT) assessments during exercise testing is an important determinant of CAD prognosis. However, many key symptoms of MDD, such as reduced interest in daily activities, lack of energy, and fatigue, may affect exercise performance and the detection of ischemia in patients with MDD. This study evaluated the extent to which MDD and depressive symptomatology moderate exercise test performance and compared the ability of ECG versus SPECT for detecting ischemia in 1367 consecutive patients who underwent exercise testing.

METHODS

All patients underwent a brief, structured psychiatric interview (PRIME-MD) and completed the Beck Depression Inventory (BDI) on the day of their exercise (treadmill) test.

RESULTS

A total of 183 patients (13%) met diagnostic criteria for MDD. Patients with MDD achieved a significantly lower percent of maximal predicted heart rate (%MPHR), exhibited lower peak exercise mets, and spent less time exercising compared with patients without MDD (all P values <.05). BDI scores were also negatively correlated with all 3 indices of exercise performance (all P values <.01). There were no differences in rates of SPECT ischemia in patients with MDD (40%) versus patients without MDD (45%; P =.23); however, rates of ECG ischemia were significantly lower (30%) in patients with MDD than in patients without MDD (48%; P <.0001).

CONCLUSIONS

Results suggest that patients with CAD who have MDD, depressive symptomatology, or both exhibit poor exercise tolerance and performance and that ECG, as compared with SPECT, may not be as reliable in detecting ischemia in patients who are depressed.

Improved exercise tolerance and quality of life with cardiac rehabilitation of older patients after myocardial infarction: results of a randomized, controlled trial

BACKGROUND

Whether cardiac rehabilitation (CR) is effective in patients older than 75 years, who have been excluded from most trials, remains unclear. We enrolled patients 46 to 86 years old in a randomized trial and assessed the effects of 2 months of post-myocardial infarction (MI) CR on total work capacity (TWC, in kilograms per meter) and health-related quality of life (HRQL).

METHODS AND RESULTS

Of 773 screened patients, 270 without cardiac failure, dementia, disability, or contraindications to exercise were randomized to outpatient, hospital-based CR (Hosp-CR), home-based CR (Home-CR), or no CR within 3 predefined age groups (middle-aged, 45 to 65 years; old, 66 to 75 years; and very old, >75 years) of 90 patients each. TWC and HRQL were determined with cycle ergometry and Sickness Impact Profile at baseline, after CR, and 6 and 12 months later. Within each age group, TWC improved with Hosp-CR and Home-CR and was unchanged with no CR. The improvement was similar in middle-aged and old persons but smaller, although still significant, in very old patients. TWC reverted toward baseline by 12 months with Hosp-CR but not with Home-CR. HRQL improved in middle-aged and old CR and control patients but only with CR in very old patients. Complications were similar across treatment and age groups. Costs were lower for Home-CR than for Hosp-CR.

CONCLUSIONS

Post-MI Hosp-CR and Home-CR are similarly effective in the short term and improve TWC and HRQL in each age group. However, with lower costs and more prolonged positive effects, Home-CR may be the treatment of choice in low-risk older patients.

Exercise capacity early after stroke

OBJECTIVE

To evaluate exercise capacity of patients with a poststroke interval of less than 1 month.

DESIGN

Prospective, cohort, observational study.

SETTING

Exercise testing laboratory in a tertiary care hospital.

PARTICIPANTS

Twenty-nine patients (mean age +/- standard deviation, 64.9+/-13.5 y) with a poststroke interval of 26.0+/-8.8 days.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Peak exercise capacity (VO(2)peak) was measured by open-circuit spirometry during maximal effort treadmill walking with 15% body-weight support.

RESULTS

Mean VO(2)peak was 14.4+/-5.1 mL. kg(-1). min(-1) or 60%+/-16% of age- and sex-related normative values for sedentary healthy adults.

CONCLUSIONS

Exercise capacity approximately 1 month after stroke was compromised. Further research is needed to elucidate the physiologic basis of this low capacity.

Number needed to treat in cardiac rehabilitation

Clinicians, patients, and health policy-makers must judge whether healthcare interventions are worth the side effects, inconvenience, and costs. The number needed to treat (NNT) provides an estimate of the number of patients who need to be treated to attain an additional favorable outcome, or to prevent an additional adverse outcome, and is the reciprocal of the absolute risk reduction. The closer the NNT is to 1.0-meaning that every patient who is treated achieves a benefit-the more effective the treatment. Traditionally, mortality has been considered a primary outcome measure of the effectiveness of cardiac rehabilitation and, if the event rates in two groups (ie, rehabilitation and usual care) are known, the absolute risk reduction can be calculated and the NNT estimated. Mortality data were derived from three meta-analyses of cardiac rehabilitation trials: one published in 1988 (n = 3614), one in 1989 (n = 4247), and one in 2001 (n = 7683). The respective estimated NNT for mortality in the meta-analyses were 32, 46, and 72 (95% confidence intervals [95% CI] 19, 1403). Improved exercise tolerance and patient-perceived health-related quality of life (HRQL) are also considered important and attainable outcomes of cardiac rehabilitation but are continuous, not dichotomous, variables. If the minimal important difference for a continuous outcome is known, then the proportions of patients who improve, remain the same, or deteriorate can be determined and the NNT estimated. Exercise tolerance and HRQL data from two randomized controlled trials of 8 weeks of rehabilitation after myocardial infarction, the Cardiac Rehabilitation in Advanced Age trial (CR-AGE; n = 270) and the McMaster Early Rehabilitation Study (MERS; n = 201) were used to estimate the NNT. In CR-AGE, the improvement in exercise tolerance was significantly greater in the rehabilitation than usual care group and the estimated NNT was 5 (95% CI 3, 13). The generic global HRQL score increased significantly in CR-AGE with rehabilitation with an estimated NNT of 12 (95% CI 5, 26) but, as the subscale group differences were not significant, the NNT was not estimated. The NNT for exercise tolerance was not estimated in MERS, as the group difference was not significant. On the other hand, specific HRQL scores in MERS increased significantly with rehabilitation giving an estimated NNT for global HRQL of 6 (95% CI 3, 21) and 6 to 10 for the HRQL sub-scales. The data and the estimated NNT from the meta-analyses of cardiac rehabilitation in large numbers of patients suggest a limited mortality effect, probably reflecting current cardiology practice. The estimated NNT from the two trials with relatively small numbers of patients suggest inconsistent exercise tolerance effects and a relatively short duration for improved HRQL. Along with the classic reporting scales, information about clinical and laboratory variables, and patient preferences, the NNT is a useful additional measure of effectiveness that provides both clinicians and patients with information about the impact of cardiac rehabilitation as secondary prevention therapy.

Exercise rehabilitation of older patients with cardiovascular disease

As the population of elderly patients with cardiovascular disease continues to increase, much research needs to be done with the goal of maintaining physical functioning and personal independence in this population. It is of particular importance to determine whether training programs can improve physical functioning in the most severely disabled older coronary patients. Effects of cardiac rehabilitation programs on other outcome measures, including psychosocial outcomes, lipid levels, insulin levels, and body composition require better study. Finally, the economic benefits of cardiac rehabilitation in the older coronary patients has received little attention, although early reports are promising. In summary, the older population with coronary disease is characterized by high rates of disability. Exercise training has been demonstrated to be safe and to improve strength, aerobic fitness capacity, endurance and physical function. It remains to be seen whether exercise training can reverse or prevent disability in a broad population of older patients with cardiovascular disease. If successful, cardiac rehabilitation programs will pay great medical, social, and economic dividends in this population.