Effect of short-term exercise intervention on cardiovascular functions and quality of life of chronic heart failure patients: A meta-analysis

Exercise-based cardiac rehabilitation for adults with heart failure

BACKGROUND

People with heart failure experience substantial disease burden that includes low exercise tolerance, poor health-related quality of life (HRQoL), increased risk of mortality and hospital admission, and high healthcare costs. The previous 2018 Cochrane review reported that exercise-based cardiac rehabilitation (ExCR) compared to no exercise control shows improvement in HRQoL and hospital admission amongst people with heart failure, as well as possible reduction in mortality over the longer term, and that these reductions appear to be consistent across patient and programme characteristics. Limitations noted by the authors of this previous Cochrane review include the following: (1) most trials were undertaken in patients with heart failure with reduced (< 45%) ejection fraction (HFrEF), and women, older people, and those with heart failure with preserved (≥ 45%) ejection fraction (HFpEF) were under-represented; and (2) most trials were undertaken in a hospital or centre-based setting.

OBJECTIVES

To assess the effects of ExCR on mortality, hospital admission, and health-related quality of life of adults with heart failure.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO and Web of Science without language restriction on 13 December 2021. We also checked the bibliographies of included studies, identified relevant systematic reviews, and two clinical trials registers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared ExCR interventions (either exercise only or exercise as part of a comprehensive cardiac rehabilitation) with a follow-up of six months or longer versus a no-exercise control (e.g. usual medical care). The study population comprised adults (≥ 18 years) with heart failure - either HFrEF or HFpEF.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were all-cause mortality, mortality due to heart failure, all-cause hospital admissions, heart failure-related hospital admissions, and HRQoL. Secondary outcomes were costs and cost-effectiveness. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included 60 trials (8728 participants) with a median of six months' follow-up. For this latest update, we identified 16 new trials (2945 new participants), in addition to the previously identified 44 trials (5783 existing participants). Although the existing evidence base predominantly includes patients with HFrEF, with New York Heart Association (NYHA) classes II and III receiving centre-based ExCR programmes, a growing body of trials includes patients with HFpEF with ExCR undertaken in a home-based setting. All included trials employed a usual care comparator with a formal no-exercise intervention as well as a wide range of active comparators, such as education, psychological intervention, or medical management. The overall risk of bias in the included trials was low or unclear, and we mostly downgraded the certainty of evidence of outcomes upon GRADE assessment. There was no evidence of a difference in the short term (up to 12 months' follow-up) in the pooled risk of all-cause mortality when comparing ExCR versus usual care (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.71 to 1.21; absolute effects 5.0% versus 5.8%; 34 trials, 36 comparisons, 3941 participants; low-certainty evidence). Only a few trials reported information on whether participants died due to heart failure. Participation in ExCR versus usual care likely reduced the risk of all-cause hospital admissions (RR 0.69, 95% CI 0.56 to 0.86; absolute effects 15.9% versus 23.8%; 23 trials, 24 comparisons, 2283 participants; moderate-certainty evidence) and heart failure-related hospital admissions (RR 0.82, 95% CI 0.49 to 1.35; absolute effects 5.6% versus 6.4%; 10 trials; 10 comparisons, 911 participants; moderate-certainty evidence) in the short term. Participation in ExCR likely improved short-term HRQoL as measured by the Minnesota Living with Heart Failure (MLWHF) questionnaire (lower scores indicate better HRQoL and a difference of 5 points or more indicates clinical importance; mean difference (MD) -7.39 points, 95% CI -10.30 to -4.77; 21 trials, 22 comparisons, 2699 participants; moderate-certainty evidence). When pooling HRQoL data measured by any questionnaire/scale, we found that ExCR may improve HRQoL in the short term, but the evidence is very uncertain (33 trials, 37 comparisons, 4769 participants; standardised mean difference (SMD) -0.52, 95% CI -0.70 to -0.34; very-low certainty evidence). ExCR effects appeared to be consistent across different models of ExCR delivery: centre- versus home-based, exercise dose, exercise only versus comprehensive programmes, and aerobic training alone versus aerobic plus resistance programmes.

AUTHORS' CONCLUSIONS

This updated Cochrane review provides additional randomised evidence (16 trials) to support the conclusions of the previous 2018 version of the review. Compared to no exercise control, whilst there was no evidence of a difference in all-cause mortality in people with heart failure, ExCR participation likely reduces the risk of all-cause hospital admissions and heart failure-related hospital admissions, and may result in important improvements in HRQoL. Importantly, this updated review provides additional evidence supporting the use of alternative modes of ExCR delivery, including home-based and digitally-supported programmes. Future ExCR trials need to focus on the recruitment of traditionally less represented heart failure patient groups including older patients, women, and those with HFpEF.

The safety of exercise for older patients with severe aortic stenosis undergoing conservative management: A narrative review

The incidence of aortic stenosis (AS) increases with age and is a serious problem in an aging society. In recent years, transcatheter aortic valve implantation (TAVI) has been performed widely; however, older patients may be ineligible for TAVI or surgical treatment because of medical ineligibility. Symptom-based rehabilitation is required for these patients to maintain and improve their physical function and ability to perform activities of daily living. No studies have examined exercise safety for older patients with severe AS who are ineligible for TAVI or surgery. We summarized the safety of exercise for older patients with severe AS, collecting 7 studies on maximal exercise stress tests and 16 studies on preoperative physical examinations. From this review, it may be unlikely that exercise under appropriate management can cause hemodynamic changes, leading to death. However, there were no studies on exercise intervention for older patients with AS who are chosen for conservative management. The optimal exercise intensity for symptomatic older patients with AS undergoing conservative management and the effects of continuous exercise intervention require future study.

Comparison of murine behavioural and physiological responses after forced exercise by electrical shock versus manual prodding

NEW FINDINGS

What is the central question of this study? Forced treadmill exercise using electrical shock is the most common technique in rodent exercise studies. Here, we examined how the use of electrical shock during forced treadmill exercise affects behavioural and physiological responses in comparison to a novel non-electrical shock technique. What is the main finding and its importance? In comparison to mice that underwent traditional treadmill running induced by electrical shock, mice that underwent forced running using a novel technique involving gentle prodding to induce running showed: (i) higher locomotor activity; (ii) less anxiety-like behaviour; and (iii) altered exercise-induced muscle pain immediately after exercise.

ABSTRACT

Animal models of exercise have been useful to understand underlying cellular and molecular mechanisms. Many studies have used methods of exercise that are unduly stressful (e.g., electrical shock to force running), potentially skewing results. Here, we compared physiological and behavioural responses of mice after exercise induced using a prodding technique that avoids electrical shock versus a traditional protocol using electrical shock. We found that exercise performance was similar for both techniques; however, the shock group demonstrated significantly lower locomotor activity and higher anxiety-like behaviour. We also observed divergent effects on muscle pain; the prodding group showed hyperalgesia immediately after exercise, whereas the shock group showed hypoalgesia. Corticosterone concentrations were elevated to a similar extent for both groups. In conclusion, mice that were exercised without shock generated similar maximal exercise performance, but postexercise these mice showed an increase in locomotor activity, less anxiety-like behaviour and altered muscle pain in comparison to mice that exercised with shock. Our data suggest that running of mice without the use of electrical shock is potentially less stressful and might be a better technique to study the physiological and behavioural responses to exercise.

Physical Therapist Clinical Practice Guideline for the Management of Individuals With Heart Failure

The American Physical Therapy Association (APTA), in conjunction with the Cardiovascular and Pulmonary Section of APTA, have commissioned the development of this clinical practice guideline to assist physical therapists in their clinical decision making when managing patients with heart failure. Physical therapists treat patients with varying degrees of impairments and limitations in activity and participation associated with heart failure pathology across the continuum of care. This document will guide physical therapist practice in the examination and treatment of patients with a known diagnosis of heart failure. The development of this clinical practice guideline followed a structured process and resulted in 9 key action statements to guide physical therapist practice. The level and quality of available evidence were graded based on specific criteria to determine the strength of each action statement. Clinical algorithms were developed to guide the physical therapist in appropriate clinical decision making. Physical therapists are encouraged to work collaboratively with other members of the health care team in implementing these action statements to improve the activity, participation, and quality of life in individuals with heart failure and reduce the incidence of heart failure-related re-admissions.

Exercise-Based Rehabilitation for Heart Failure: Cochrane Systematic Review, Meta-Analysis, and Trial Sequential Analysis

OBJECTIVES

This study performed a contemporary systematic review and meta-analysis of exercise-based cardiac rehabilitation (ExCR) for heart failure (HF).

BACKGROUND

There is an increasing call for trials of models of ExCR for patients with HF that provide alternatives to conventional center-based provision and recruitment of patients that reflect a broader HF population.

METHODS

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL, and PsycINFO databases were searched between January 2013 and January 2018. Randomized trials comparing patients undergoing ExCR to control patients not undergoing exercise were included. Study outcomes were pooled using meta-analysis. Metaregression examined potential effect modification according to ExCR program characteristics, and risk of bias, trial sequential analysis (TSA), and Grading of Recommendations Assessment Development and Evaluation (GRADE) were applied.

RESULTS

Across 44 trials (n = 5,783; median follow-up of 6 months), compared with control subjects, ExCR did not reduce the risk of all-cause mortality (relative risk [RR]: 0.89; 95% confidence interval [CI]: 0.66 to 1.21; TSA-adjusted CI: 0.26 to 3.10) but did reduce all-cause hospitalization (RR: 0.70; 95% CI: 0.60 to 0.83; TSA-adjusted CI: 0.54 to 0.92) and HF-specific hospitalization (RR: 0.59; 95% CI: 0.42 to 0.84; TSA-adjusted CI: 0.14 for 2.46), and patients reported improved Minnesota Living with Heart Failure questionnaire overall scores (mean difference: -7.1; 95% CI: -10.5 to -3.7; TSA-adjusted CI: -13.2 to -1.0). No evidence of differential effects across different models of delivery, including center- versus home-based programs, were found.

CONCLUSIONS

This review supports the beneficial effects of ExCR on patient outcomes. These benefits appear to be consistent across ExCR program characteristics. GRADE and TSA assessments indicated that further high-quality randomized trials are needed.

Exercise-based cardiac rehabilitation for adults with heart failure

BACKGROUND

Chronic heart failure (HF) is a growing global health challenge. People with HF experience substantial burden that includes low exercise tolerance, poor health-related quality of life (HRQoL), increased risk of mortality and hospital admission, and high healthcare costs. The previous (2014) Cochrane systematic review reported that exercise-based cardiac rehabilitation (CR) compared to no exercise control shows improvement in HRQoL and hospital admission among people with HF, as well as possible reduction in mortality over the longer term, and that these reductions appear to be consistent across patient and programme characteristics. Limitations noted by the authors of this previous Cochrane Review include the following: (1) most trials were undertaken in patients with HF with reduced (< 45%) ejection fraction (HFrEF), and women, older people, and those with preserved (≥ 45%) ejection fraction HF (HFpEF) were under-represented; and (2) most trials were undertaken in the hospital/centre-based setting.

OBJECTIVES

To determine the effects of exercise-based cardiac rehabilitation on mortality, hospital admission, and health-related quality of life of people with heart failure.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and three other databases on 29 January 2018. We also checked the bibliographies of systematic reviews and two trial registers.

SELECTION CRITERIA

We included randomised controlled trials that compared exercise-based CR interventions with six months' or longer follow-up versus a no exercise control that could include usual medical care. The study population comprised adults (> 18 years) with evidence of HF - either HFrEF or HFpEF.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all identified references and rejected those that were clearly ineligible for inclusion in the review. We obtained full papers of potentially relevant trials. Two review authors independently extracted data from the included trials, assessed their risk of bias, and performed GRADE analyses.

MAIN RESULTS

We included 44 trials (5783 participants with HF) with a median of six months' follow-up. For this latest update, we identified 11 new trials (N = 1040), in addition to the previously identified 33 trials. Although the evidence base includes predominantly patients with HFrEF with New York Heart Association classes II and III receiving centre-based exercise-based CR programmes, a growing body of studies include patients with HFpEF and are undertaken in a home-based setting. All included studies included a no formal exercise training intervention comparator. However, a wide range of comparators were seen across studies that included active intervention (i.e. education, psychological intervention) or usual medical care alone. The overall risk of bias of included trials was low or unclear, and we downgraded results using the GRADE tool for all but one outcome.Cardiac rehabilitation may make little or no difference in all-cause mortality over the short term (≤ one year of follow-up) (27 trials, 28 comparisons (2596 participants): intervention 67/1302 (5.1%) vs control 75/1294 (5.8%); risk ratio (RR) 0.89, 95% confidence interval (CI) 0.66 to 1.21; low-quality GRADE evidence) but may improve all-cause mortality in the long term (> 12 months follow up) (6 trials/comparisons (2845 participants): intervention 244/1418 (17.2%) vs control 280/1427 (19.6%) events): RR 0.88, 95% CI 0.75 to 1.02; high-quality evidence). Researchers provided no data on deaths due to HF. CR probably reduces overall hospital admissions in the short term (up to one year of follow-up) (21 trials, 21 comparisons (2182 participants): (intervention 180/1093 (16.5%) vs control 258/1089 (23.7%); RR 0.70, 95% CI 0.60 to 0.83; moderate-quality evidence, number needed to treat: 14) and may reduce HF-specific hospitalisation (14 trials, 15 comparisons (1114 participants): (intervention 40/562 (7.1%) vs control 61/552 (11.1%) RR 0.59, 95% CI 0.42 to 0.84; low-quality evidence, number needed to treat: 25). After CR, a clinically important improvement in short-term disease-specific health-related quality of life may be evident (Minnesota Living With Heart Failure questionnaire - 17 trials, 18 comparisons (1995 participants): mean difference (MD) -7.11 points, 95% CI -10.49 to -3.73; low-quality evidence). Pooling across all studies, regardless of the HRQoL measure used, shows there may be clinically important improvement with exercise (26 trials, 29 comparisons (3833 participants); standardised mean difference (SMD) -0.60, 95% CI -0.82 to -0.39; I² = 87%; Chi² = 215.03; low-quality evidence). ExCR effects appeared to be consistent different models of ExCR delivery: centre vs. home-based, exercise dose, exercise only vs. comprehensive programmes, and aerobic training alone vs aerobic plus resistance programmes.

AUTHORS' CONCLUSIONS

This updated Cochrane Review provides additional randomised evidence (11 trials) to support the conclusions of the previous version (2014) of this Cochane Review. Compared to no exercise control, CR appears to have no impact on mortality in the short term (< 12 months' follow-up). Low- to moderate-quality evidence shows that CR probably reduces the risk of all-cause hospital admissions and may reduce HF-specific hospital admissions in the short term (up to 12 months). CR may confer a clinically important improvement in health-related quality of life, although we remain uncertain about this because the evidence is of low quality. Future ExCR trials need to continue to consider the recruitment of traditionally less represented HF patient groups including older, female, and HFpEF patients, and alternative CR delivery settings including home- and using technology-based programmes.

Reported methods for handling missing change standard deviations in meta-analyses of exercise therapy interventions in patients with heart failure: A systematic review

Background

Well-constructed systematic reviews and meta-analyses are key tools in evidenced-based healthcare. However, a common problem with performing a meta-analysis is missing data, such as standard deviations (SD). An increasing number of methods are utilised to calculate or impute missing SDs, allowing these studies to be included in analyses. The aim of this review was to investigate the methods reported and utilised for handling missing change SDs in meta-analyses, using the topic of exercise therapy in heart failure patients as a model.

Methods

A systematic search of PubMed, EMBASE and Cochrane Library from 1 January 2014 to 31st March 2018 was conducted for meta-analyses of exercise based trials in heart failure. Studies were eligible to be included if they performed a meta-analysis of change in exercise capacity in heart failure patients after a training intervention.

Results

Twenty two publications performed a meta-analysis on the effect of exercise therapy on exercise capacity in heart failure patients. Eleven (50%) publications did not directly report the approach for dealing with missing change SDs. Approaches reported and utilised to deal with missing change SDs included imputation, actual and approximate algebraic recalculation using study level summary statistics and exclusion of studies.

Conclusion

Change SDs are often not reported in trial papers and while in the first instance meta-analysts should attempt to obtain missing data from trial authors, this information is frequently not forthcoming. Meta-analysts are then forced to make a decision on how these trials and missing data are to be handled. Whilst not one approach is favoured for dealing with this matter, authors need to clearly report the approach to be utilised for missing change SDs. Where change SDs are imputed meta-analyst are encouraged to explore several options and have a sound rationale as to the choice, and where data is imputed, sensitivity analysis should be conducted.

Effects of exercise modalities on central hemodynamics, arterial stiffness and cardiac function in cardiovascular disease: Systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Exercise is accepted as an important contribution to the rehabilitation of patients with cardiovascular disease (CVD). This study aims to better understand the possible causes for lack of consensus and reviews the effects of three exercise modalities (aerobic, resistance and combined exercise) on central hemodynamics, arterial stiffness and cardiac function for better rehabilitation strategies in CVD.

METHODS

The electronic data sources, Cochrane Library, MEDLINE, Web of Science, EBSCO (CINAHL), and ScienceDirect from inception to July 2017 were searched for randomized controlled trials (RCTs) investigating the effect of exercise modalities in adult patients with CVD. The effect size was estimated as mean differences (MD) with 95% confidence intervals (CI). Subgroup analysis and meta-regression were used to study potential moderating factors.

RESULTS

Thirty-eight articles describing RCTs with a total of 2089 patients with CVD were included. The pooling revealed that aerobic exercise [MD(95%CI) = -5.87 (-8.85, -2.88), P = 0.0001] and resistance exercise [MD(95%CI) = -7.62 (-10.69, -4.54), P<0.00001] significantly decreased aortic systolic pressure (ASP). Resistance exercise significantly decreased aortic diastolic pressure [MD(95%CI) = -4(-5.63, -2.37), P<0.00001]. Aerobic exercise significantly decreased augmentation index (AIx) based on 24-week exercise duration and patients aged 50-60 years. Meanwhile, aerobic exercise significantly improved carotid-femoral pulse wave velocity (cf-PWV) [MD(95%CI) = -0.42 (-0.83, -0.01), P = 0.04], cardiac output (CO) [MD(95% CI) = 0.36(0.08, 0.64), P = 0.01] and left ventricular ejection fraction (LVEF) [MD(95%CI) = 3.02 (2.11, 3.93), P<0.00001]. Combined exercise significantly improved cf-PWV [MD(95%CI) = -1.15 (-1.95, -0.36), P = 0.004] and CO [MD(95% CI) = 0.9 (0.39, 1.41), P = 0.0006].

CONCLUSIONS

Aerobic and resistance exercise significantly decreased ASP, and long-term aerobic exercise reduced AIx. Meanwhile, aerobic and combined exercise significantly improved central arterial stiffness and cardiac function in patients with CVD. These findings suggest that a well-planned regime could optimize the beneficial effects of exercise and can provide some evidence-based guidance for those involved in cardiovascular rehabilitation of patients with CVD.