Effects of exercise training on cardiovascular risk factors in kidney transplant recipients: a systematic review and meta-analysis

A mendelian randomization study revealing that metabolic syndrome is causally related to renal failure

Background

The onset and progression of chronic kidney disease (CKD) has been linked to metabolic syndrome (MetS), with the results of recent observational studies supporting a potential link between renal failure and MetS. The causal nature of this relationship, however, remains uncertain. This study thus leveraged a Mendelian Randomization (MR) approach to probe the causal link of MetS with renal failure.

Methods

A genetic database was initially used to identify SNPs associated with MetS and components thereof, after which causality was evaluated through the inverse variance weighted (IVW), MR-Egger regression, and weighted media techniques. Results were subsequently validated through sensitivity analyses.

Results

IVW (OR = 1.48, 95% CI = 1.21-1.82, P =1.60E-04) and weighted median (OR = 1.58, 95% CI =1.15-2.17, P = 4.64E-03) analyses revealed that MetS was linked to an elevated risk of renal failure. When evaluating the specific components of MetS, waist circumference was found to be causally related to renal failure using the IVW (OR= 1.58, 95% CI = 1.39-1.81, P = 1.74e-11), MR-Egger (OR= 1.54, 95% CI = 1.03-2.29, P = 0.036), and weighted median (OR= 1.82, 95% CI = 1.48-2.24, P = 1.17e-8). The IVW method also revealed a causal association of hypertension with renal failure (OR= 1.95, 95% CI = 1.34-2.86, P = 5.42e-04), while renal failure was not causally related to fasting blood glucose, triglyceride levels, or HDL-C levels.

Conclusion

These data offer further support for the existence of a causal association of MetS with kidney failure. It is thus vital that MetS be effectively managed in patients with CKD in clinical settings, particularly for patients with hypertension or a high waist circumference who are obese. Adequate interventions in these patient populations have the potential to prevent or delay the development of renal failure.

Rehabilitation exercises for kidney transplant recipients in an organ transplant ward: a best practice implementation project

INTRODUCTION AND OBJECTIVES

Kidney transplantation is an effective treatment for end-stage kidney disease. Kidney transplant recipients (KTRs) are prone to experiencing reduced physical function, depression, fatigue, and lack of exercise motivation due to their sedentary lifestyle before surgery. Exercise is an effective intervention for KTRs, but it has not been properly implemented in many practice settings. This project aimed to promote evidence-based exercises as part of KTRs' rehabilitation to improve their health outcomes.

METHODS

This project was informed by the JBI Evidence Implementation Framework. The project was conducted in the organ transplant ward of a tertiary comprehensive hospital in Changsha, China. Based on a summary of best evidence, 12 audit criteria were developed for the baseline and follow-up audits involving 30 patients and 20 nursing staff. The JBI Practical Application of Clinical Evidence System (PACES) and Getting Research into Practice (GRiP) tool were used to identify barriers and facilitators and develop targeted strategies to improve issues.

RESULTS

Compared with the baseline audit, significant improvements were achieved in most of the criteria in the follow-up audit, with 9 of the 12 criteria reaching 100% compliance. Notably, the 6-minute walk distance test results were significantly higher, while the Self-Rating Depression Scale and Self-Rating Anxiety Scale scores were significantly lower (p < 0.05).

CONCLUSIONS

This project demonstrates that evidence-based practice can improve the clinical practice of rehabilitation exercises for KTRs. The GRiP strategies proved to be extremely useful, notably, the formulation of a standardized rehabilitation exercise protocol, training, and enhancement of the exercising environment. Head nurses' leadership and decision-making also played an important role in the success of this project.

SPANISH ABSTRACT

http://links.lww.com/IJEBH/A180.

Systematic review and meta-analysis of the efficacy of exercise intervention in kidney transplant recipients

BACKGROUND AND OBJECTIVE

There is uncertainty about the beneficial effects of exercise intervention for kidney transplant recipients. The purpose of our meta-analysis is to estimate the efficacy of exercise intervention in kidney transplant recipients.

METHODS

A database search according to the PICOS framework was performed for all published randomized, double-blind, placebo-controlled trials (RCTs) about exercise intervention for kidney transplant recipients. The databases involved include PubMed, Embase, and Cochrane Library.

RESULTS

A total of 16 RCTs (involving 827 patients) in compliance with inclusion criteria were included in our study. The results demonstrated that adequate exercise intervention improved statistically in creatinine clearance [mean difference (MD) =  - 0.29, 95% confidence interval (CI) - 0.46 to - 0.11, p = 0.001], serum urea (MD = - 21.57, 95% CI - 35.84 to - 7.29, p = 0.003), VO2 peak (MD = 3.20, 95% CI 1.97-4.43, p < 0.00001), high-density lipoprotein-cholesterol (HDL-C) (MD = 0.21, 95% CI 0.04-0.37, p = 0.01), 60-s sit to stand test (60-STS) (MD = 14.47, 95% CI 8.89-20.04, p < 0.00001), 6-min walk distance (6-MWD) (MD = 91.87, 95% CI 38.34-145.39, p = 0.0008), and 6-min walk test (6-MWT) (MD = 44.08, 95% CI 20.30-67.87, p = 0.0003) of patients after kidney transplantation. No between-groups differences (p > 0.05) were observed for anthropometric characteristics, body composition, serum cytokine levels, and quality of life short form-36 questionnaire (SF-36).

CONCLUSIONS

In kidney transplant recipients, appropriate exercise intervention improved renal function, cardiopulmonary function, physical performance.

TRIAL REGISTRATION

The PROSPERO registration number is CRD42022357574.

The Moderating Role of Health Variables on the Association between Physical Exercise and Quality of Life in Patients with End-Stage Renal Disease

Scientific evidence demonstrates the positive impact that physical exercise has on the quality of life (QOL) of patients with chronic kidney disease (CKD). However, no study has proposed a model investigating the effect physical exercise has on the QOL of end-stage renal disease (ESRD) patients, considering the most frequent associated diseases (diabetes/hypertension). The objectives were (1) to explore the relationship between physical exercise and the QOL of adults with ESRD, and (2) to examine the moderating and/or mediating role of relevant patient variables. This non-interventional study utilized an ex post facto retrospective data analysis design with a sample of 310 patients with ESRD through two validated questionnaires. The dependent variables were the QOL scale (KDQOL-SF), and the physical function dimension (EFFISICA). The independent variables were the regular practice of intense physical activity (DEPINTE) and the daily time (in hours) the patient is in a sedentary attitude (TiParado). The moderating variables were the clinical situation and associated diseases. The mediator variable used was the body mass index. Bivariate and multiple regression analyses were conducted. Findings suggest implementing intense physical activity in transplant recipients and programmes to avoid sedentary lifestyles in dialysis patients have a positive effect in the QOL of ESRD patients.

Exercise and chronic kidney disease: potential mechanisms underlying the physiological benefits

Increasing evidence indicates that exercise has beneficial effects on chronic inflammation, cardiorespiratory function, muscle and bone strength and metabolic markers in adults with chronic kidney disease (CKD), kidney failure or kidney transplants. However, the mechanisms that underlie these benefits have received little attention, and the available clinical evidence is mainly from small, short-duration (<12 weeks) exercise intervention studies. The available data, mainly from patients with CKD or on dialysis, suggest that exercise-mediated shifts towards a less inflammatory immune cell profile, enhanced activity of the NRF2 pathway and reduced monocyte infiltration into adipose tissue may underlie improvements in inflammatory biomarkers. Exercise-mediated increases in nitric oxide release and bioavailability, reduced angiotensin II accumulation in the heart, left ventricular remodelling and reductions in myocardial fibrosis may contribute to improvements in left ventricular hypertrophy. Exercise stimulates an anabolic response in skeletal muscle in CKD, but increases in mitochondrial mass and satellite cell activation seem to be impaired in this population. Exercise-mediated activation of the canonical wnt pathway may lead to bone formation and improvements in the levels of the bone-derived hormones klotho and fibroblast growth factor 23 (FGF23). Longer duration studies with larger sample sizes are needed to confirm these mechanisms in CKD, kidney failure and kidney transplant populations and provide evidence for targeted exercise interventions.

Predicting physical activity in kidney transplant recipients: an application of the Health Action Process Approach model

Despite numerous physical, psychological, and social benefits of physical activity (PA), few kidney transplant recipients (KTRs) positively participate in PA. It is essential to understand the influencing factors of PA in KTRs. This study aimed to apply the Health Action Process Approach (HAPA) model to explore the influencing factors of PA in KTRs. This was a prospective study involving 320 participants. Pre-actional self-efficacy, outcome expectancies, risk perception, social support, PA intention, and demographic and clinical data were measured at Time 1. Coping self-efficacy, planning, recovery self-efficacy, and PA behavior were assessed 3 months later. The hypothesized relationships were examined by structural equation modeling. Findings revealed significant direct effects of pre-actional self-efficacy, negative outcome expectancies, positive outcome expectancies, and social support on intention. Planning and recovery self-efficacy were significant predictors of PA. The HAPA model provided a validated and useful framework for predicting the factors influencing PA behavior in KTRs.

The Effects of 24 Weeks of Non-Face-to-Face Home Exercise on Body Composition, Physical Fitness, Cardiovascular Function, and Blood Profiles in Pre-Metabolic Syndrome Korean Adults: A Pilot Study

Background: This study assessed Korean residents’ health improvements by reducing chronic disease morbidity through customized health management. After identifying each participant’s strength and health through physical examinations and blood pressure tests, the effects of 24 weeks of online, non-face-to-face home workouts on body composition, physical fitness, cardiovascular function, and blood profiles in Korean adults with pre-metabolic syndrome were determined. Methods: Adults living in Chungcheongbuk-do, aged 19−65, and at the pre-metabolic syndrome stage were recruited at the Jeungpyeong-gun Public Health Center, Chungcheongbuk-do, Korea. For 24 weeks, from February 2022 to July 2022, they exercised for 60−70 min, three times a week, on average, at a maximum heart rate of 60−70%. The “Mobile Healthcare” application was used to record exercise time, number of exercises, number of sets, and Rating of Perceived Exertion at the end of each exercise. Body composition, physical fitness, cardiovascular function, and blood profiles were measured before and after participation. Results: There were no significant differences in weight, body mass index, body fat, waist-to-hip ratio, waist circumference, systolic blood pressure, diastolic blood pressure, resting heart rate levels, or glucose levels after participation in the workout (p > 0.05). However, muscle strength/handgrip strength, sitting-rising test results, single-leg balance, triglycerides, high-density lipoprotein, low-density lipoprotein, and total cholesterol showed a statistically significant difference (p < 0.05). Conclusions: Although the 24 weeks of non-face-to-face home workouts did not positively affect body composition or cardiovascular function, it improved physical fitness and dyslipidemia.

Therapeutic effects of exercise interventions for patients with chronic kidney disease: an umbrella review of systematic reviews and meta-analyses

OBJECTIVE

To conduct an overview of meta-analyses evaluating the impact of exercise interventions on improving health outcomes in patients with chronic kidney disease (CKD).

DESIGN

An umbrella review of systematic review and meta-analyses of intervention trials was performed.

DATA SOURCES

PubMed, Web of Science, Embase and the Cochrane Database of Systematic Reviews were searched from inception to 9 March 2021 for relevant articles.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Eligible meta-analyses compared the effects of usual care with and without exercise in patients with CKD. Health outcomes included those related to cardiovascular risk factors, physical fitness, dialysis-related symptoms, dialysis adequacy and health-related quality of life. Systematic reviews and meta-analyses that included fewer than 3 RCTs or fewer than 100 participants were excluded from the analysis.

RESULTS

A total of 31 eligible systematic reviews and meta-analyses were included that assessed 120 outcomes. For physical fitness, there was a moderate effect size for cardiorespiratory fitness, muscle strength and body composition and small effect size for muscle endurance. The effect sizes for cardiovascular risk factors, dialysis-related symptoms and health-related quality of life outcomes were small. According to the Grading of Recommendations Assessment, Development and Evaluation framework, most outcomes were low or very low quality.

CONCLUSION

Exercise appears to be a safe way to affect concomitant cardiovascular risk factors, such as blood pressure, improve physical fitness and health-related quality of life and reduce dialysis-related symptoms in patients with CKD.

PROSPERO REGISTRATION NUMBER

CRD42020223591.

Association of Exercise With Vascular Function in Patients With CKD: A Meta-Analysis of Randomized Controlled Trials

Background and Aim

Vascular function is associated with an increased risk of cardiovascular events in patients with chronic kidney disease (CKD). Whether exercise improves vascular function in such patients remains controversial. This study aimed to conduct a meta-analysis on the effect of exercise training on the vascular function of patients with CKD.

Methods

Embase, the Cochrane Central Register of Controlled Trials, and Medline were searched from inception until November 15, 2021. The terms exercise, CKD, dialysis, kidney transplant, and randomized controlled trial (RCT) were searched alone or in combination. RCTs were included when studies compared exercise with active control, usual care, or no intervention, and the studies reported vascular function on patients with CKD.

Results

This meta-analysis included 18 RCTs with 817 patients. Exercise training was significantly associated with decreased pulse wave velocity weighted mean difference (WMD), −0.56; 95% confidence interval (CI), −1.02 to −0.09, P = 0.02 and augmentation index (WMD, −3.26; 95% CI, −5.46 to −1.05, P = 0.004). It was also significantly associated with improved peak VO2 (WMD, 2.64; 95% CI, 1.94–3.35, P < 0.00001), general health (WMD, 7.03; 95% CI, 0.65–13.42, P = 0.03), and vitality (WMD, 9.1; 95% CI, 2.50–15.69, P = 0.007).

Conclusions

The meta-analysis suggested that exercise training improved vascular function in patients with CKD. An exercise program should be considered as one of the management strategies for vascular dysfunction in patients with CKD. Further studies are needed to demonstrate that exercise training improves cardiovascular diseases in patients with CKD.

Frailty and Kidney Transplantation: A Systematic Review and Meta-analysis

Frailty is a multidimensional condition and is the result of the body's age-associated decline in physical, cognitive, physiological, and immune reserves. The aim of this systematic review is to assess the quality of evidence of the included studies, determine the prevalence of frailty among kidney transplant candidates, and evaluate the relationship between frailty and associated patient characteristics and outcomes after kidney transplantation.

METHODS

A systematic search was performed for relevant literature on frailty and kidney transplantation. This was followed by a meta-analysis for patient characteristics and outcomes reported by a minimum of 2 studies including mean age, gender, mean body mass index, type of kidney transplantation, dialysis, previous kidney transplantation, comorbidities, hypertension, race, preemptive kidney transplantation, delayed graft function, and length of stay.

RESULTS

A total of 18 studies were included in the systematic review and 14 of those studies were suitable for meta-analysis. The overall pooled prevalence of frailty before transplantation was estimated at 17.1% (95% confidence interval [CI], 15.4-18.7). Frailty was significantly associated with higher age (mean difference, 3.6; 95% CI, 1.4-5.9), lower rate of preemptive transplantation (relative risk, 0.60; 95% CI, 0.4-0.9), longer duration of delayed graft function (relative risk, 1.80; 95% CI, 1.1-3.0), and length of stay longer than 2 wk (odds ratio, 1.64; 95% CI, 1.2-2.3).

CONCLUSIONS

One in 6 kidney transplant recipients is frail before transplantation. The presence of frailty is associated with lower rates of preemptive transplantation, older recipient age, higher rates of delayed graft function, and longer length of stay. Future research is required to explore the association of frailty with other adverse outcomes after kidney transplantation and the effects of intervention programs to improve the different frailty domains.

Personalized physical rehabilitation program and employment in kidney transplant recipients: a randomized trial

Kidney transplantation is the preferred treatment for kidney failure; however after transplant, reduced physical function, poor self-perceptions, and unemployment are common concerns that remain. This randomized controlled trial compared the effects of a 12-month exercise rehabilitation program (intervention) to standard care alone (control) in kidney transplant recipients. The exercise intervention consisted of a 2 day/week, 60-minute personalized, one-on-one, resistance-based exercise trainings. Eighty participants completed the study (52 intervention vs. 28 control). For individuals unemployed at baseline, there was a 52.3% increase in employment compared to 13.3 % increase in the control group after 12 months (P = <0.0001). For those already employed at baseline, 100% of individuals maintained employment in both groups after 12 months (P = 0.4742). For all comers, there was a positive trend for Global Physical Health (P = 0.0034), Global Mental Health (P = 0.0064), and Physical Function (P = 0.0075), with the intervention group showing greater improvements. These findings suggest the implementation of an exercise rehabilitation program postkidney transplant can be beneficial to increase employment for individuals previously unemployed, improve self-perceived health, physical function, and mental health, overall contributing to better health outcomes in kidney transplant recipients. (Clinicaltrials.gov number: NCT02409901).

The effects of exercise training in adult solid organ transplant recipients: A systematic review and meta-analysis

Reduced exercise capacity can predispose solid organ transplant (SOT) recipients to higher risk of diabetes, cardiovascular complications, and mortality and impact their quality of life. This systematic review and meta-analysis investigated the effects of exercise training (versus no training) in adult SOT recipients. We conducted an electronic search of randomized controlled trials reporting on exercise interventions in SOT recipients. Primary outcomes were exercise capacity, quadriceps muscle strength, and health-related quality of life (HRQoL). Twenty-nine articles met the inclusion criteria. In 24 studies, there were either high risk of bias or some concerns about the potential risk of bias. There was an increase in exercise capacity (VO₂ peak) (SMD: 0.40; 95%CI 0.22-0.57; P = 0.0) and quadriceps muscle strength (SMD: 0.38; 95%CI 0.16-0.60; P = 0.001) in the exercise vs control groups. There were also improvements in several domains of the SF-36. Diastolic blood pressure improved in the exercise group compared to controls (SMD: -0.22; 95%CI -0.41-0.03; P = 0.02). Despite the considerable variation in exercise training characteristics and high risk of bias in the included studies, exercise training improved maximal exercise capacity, quadriceps muscle strength, HRQoL, and diastolic blood pressure and should be an essential part of the post-transplant care.

Physical activity and renal function in the Italian kidney transplant population

Background

The well-documented benefits of physical activity (PA) are still poorly characterized in long-term kidney transplant outcome. This study analyzed the impact over a 10-year follow-up of PA on graft function in Italian kidney transplant recipients (KTRs).

Methods

Since 2002, the Italian Transplant-Information-System collected donor and recipient baseline and transplant-related parameters in KTRs. In 2015, ‘penchant for PA’ (PA ≥ 30-min, 5 times/week) was added. Stable patients aged ≥18 years at the time of first-transplantation were eligible. KTRs with at least 10-year follow-up were also analyzed. Mixed-effect regression models were used to compare eGFR changes over time in active versus non-active patients.

Results

PA information was available for 6,055 KTRs (active 51.6%, non-active 48.4%). Lower penchant for PA was found in overweight and obese patients (OR = 0.84; OR = 0.48, respectively), in those with longer dialysis vintage (OR = 0.98 every year of dialysis), and older age at transplant. Male subjects showed greater penchant for PA (OR = 1.25). A slower decline of eGFR over time was observed in active KTRs compared to non-active, and this finding was confirmed in the subgroup with at least 10-year follow-up (n = 2,060). After applying the propensity score matching to reduce confounding factors, mixed-effect regression models corroborated such better long-term trend of graft function preservation in active KTRs.

Conclusions

Penchant for PA is more frequent among male and younger KTRs. Moreover, in our group of Italian KTRs, active patients revealed higher eGFR values and preserved kidney function over time, up to 10-years of follow-up.

A Pilot Randomized Controlled Trial Using SystemCHANGE™ Approach to Increase Physical Activity in Older Kidney Transplant Recipients

BACKGROUND

Cardiovascular disease is the leading cause of death in kidney transplant recipients. Physical activity after transplant is the most modifiable nonpharmacological factor for improving cardiovascular outcomes. Few studies have tested walking interventions to enhance daily steps and health outcomes in older kidney recipients.

METHODS

Using a pilot feasibility randomized clinical trial design, we tested the feasibility and efficacy of a 6-month SystemCHANGE™ (Change Habits by Applying New Goals and Experience) + Activity Tracker intervention for recruitment, retention, daily steps, and health outcomes (blood pressure, heart rate, body mass index, waist circumference, and physical function). The SystemCHANGE™ + Activity Tracker intervention taught participants to use a multicomponent intervention that connects person-centered systems solutions combined with visual feedback from a mobile activity tracker to achieve daily step goals.

RESULTS

Fifty-three participants (mean age 65 years, 66% male, and 57% white) participated with 27 in the intervention and 26 in the control group. The study protocol was feasible to deliver with high adherence to the protocol in both groups. The intervention group increased daily steps at 3 months (mean difference, 608; standard error = 283, P = .03) compared to the control group. The secondary outcome of heart rate decreased for the intervention group (baseline [mean] 74.4+ 10.8 [standard deviation, SD;] vs 6 months [mean] 67.6+ 11.3 [SD]; P = .002) compared to the control group (baseline [mean] 70.67+ 10.4 [SD]; vs 6 months [mean] 70.2 + 11.1 [SD]; P = .83).

CONCLUSIONS

SystemCHANGE™ + Activity Tracker intervention appears to be feasible and efficacious for increasing daily steps in older kidney recipients.

Advances in exercise therapy in predialysis chronic kidney disease, hemodialysis, peritoneal dialysis, and kidney transplantation

PURPOSE OF REVIEW

Chronic kidney disease (CKD) is characterized by poor levels of physical activity which contribute to increased morbidity across the disease trajectory. The short nature, small samples, and poor methodology across most studies have failed to translate the role of exercise in CKD into its adoption as a frontline adjunct therapeutic option. This review focuses on recent advances surrounding the benefits of exercise interventions across the CKD spectrum.

RECENT FINDINGS

Key recent advances in exercise studies have focused on the efficacy of novel intervention strategies across the CKD spectrum. These include high-intensity interval training, virtual reality gaming, intradialytic yoga, electrical stimulation of muscles, blood flow restriction training, and protocols combining exercise with nutritional supplementation. Research is also beginning to explore the role of prehabilitation for patients prior to dialysis and kidney transplantation.

SUMMARY

Studies continue to demonstrate wide-ranging benefits of exercise across CKD; however, implementation of exercise remains scarce. Future research needs include evaluating the efficacy of larger and/or more comprehensive interventions on clinically important outcomes. It is hoped with increasing global evidence, high-quality clinical studies, and sustained clinician and patient engagement, exercise programs will become better prioritized in the nephrology field.