Effects of exercise training on aerobic and functional capacity of end-stage renal disease patients

Quantifying the dose-response relationship between exercise and health-related quality of life in patients undergoing haemodialysis: A meta-analysis

Objective

This meta-analysis aims to explore the dose-response relationship of aerobic exercise or aerobic combined resistance exercise on cardiopulmonary function in maintenance hemodialysis（MHD）, with the goal of aiding in the formulation of precise exercise prescriptions.

Methods

A literature search up to August 18, 2023, was conducted in databases including Web of Science, among others, focusing on the effects of exercise interventions on cardiopulmonary function in hemodialysis patients.Two researchers independently conducted literature screening, data extraction, and an assessment of study methodology quality. A dose-response meta-analysis was carried out using a one-stage cubic spline mixed-effects model, followed by stratified analyses based on intervention period, intervention method, and exercise environment.

Results

A nonlinear dose-response relationship was observed between exercise and 6-minute walk test (6WMT) as well as peak oxygen uptake (VO2Peak) in hemodialysis patients. The optimal exercise dose for the 6WMT across the full exposure range was 922 METs-min/week, with VO2Peak increasing with the dose. The effects were influenced by the type of exercise, intervention period, and exercise environment. An exercise dose of 500 METs-min/week and 619 METs-min/week was found sufficient to achieve the minimal clinically important differences (MCID) for 6WMT and VO2Peak, respectively.

Conclusion

There is a significant association between the dose of exercise and its effects. With appropriate adjustment of variables, even low-dose exercise can lead to clinically significant improvements in cardiopulmonary function.

Modifiable Physical Factors That Influence Physical Function for People Receiving Peritoneal Dialysis

Introduction

People receiving peritoneal dialysis experience physical function decline, impairing their ability to complete everyday activities, leading to poorer quality of life. Physical factors, including cardiorespiratory fitness, muscle strength, physical activity, and sedentary behavior are associated with physical function. However, little is known about this relationship, or temporal changes of these factors in this cohort. This study aimed to explore modifiable physical factors that are associated with physical function, identify which factor has the strongest influence, and explore temporal changes.

Methods

Adults receiving peritoneal dialysis underwent objective and self-reported physical function, cardiorespiratory fitness, muscle strength, physical activity and sedentary behavior assessments 3 times over a 12-month observation period (at baseline, 6 months, and 12 months).

Results

Eighty-two participants underwent assessments. All modifiable physical factors were predominantly moderate to strongly associated with physical function at baseline. Cardiorespiratory fitness had the strongest and most consistent influence with every meter conferring a 0.08-unit (P < 0.01) and 0.01-unit (P < 0.05) increase in self-report and objective physical function score, respectively. Temporal changes were observed for modifiable physical factors with significant mean changes in cardiorespiratory fitness (-9.8%), quadricep strength (-5%), moderate-to-vigorous (-25.9%) and total (-16.2%) physical activity, and sedentary behavior (+7.1%).

Conclusion

The results of this study indicate that cardiorespiratory fitness could be routinely monitored to detect risk of physical function decline and targeted through intervention to enhance physical function for people receiving peritoneal dialysis. Nevertheless, all factors should be considered when designing interventions to mitigate temporal changes and induce the numerous health benefits offered by being physically active.

Exercise for patients with chronic kidney disease: from cells to systems to function

Chronic kidney disease (CKD) is among the leading causes of death and disability, affecting an estimated 800 million adults globally. The underlying pathophysiology of CKD is complex creating challenges to its management. Primary risk factors for the development and progression of CKD include diabetes mellitus, hypertension, age, obesity, diet, inflammation, and physical inactivity. The high prevalence of diabetes and hypertension in patients with CKD increases the risk for secondary consequences such as cardiovascular disease and peripheral neuropathy. Moreover, the increased prevalence of obesity and chronic levels of systemic inflammation in CKD have downstream effects on critical cellular functions regulating homeostasis. The combination of these factors results in the deterioration of health and functional capacity in those living with CKD. Exercise offers protective benefits for the maintenance of health and function with age, even in the presence of CKD. Despite accumulating data supporting the implementation of exercise for the promotion of health and function in patients with CKD, a thorough description of the responses and adaptations to exercise at the cellular, system, and whole body levels is currently lacking. Therefore, the purpose of this review is to provide an up-to-date comprehensive review of the effects of exercise training on vascular endothelial progenitor cells at the cellular level; cardiovascular, musculoskeletal, and neural factors at the system level; and physical function, frailty, and fatigability at the whole body level in patients with CKD.

Measurement properties of performance-based measures to assess physical function in chronic kidney disease: recommendations from a COSMIN systematic review

Background

There is wide heterogeneity in physical function tests available for clinical and research use, hindering our ability to synthesize evidence. The aim of this review was to identify and evaluate physical function measures that could be recommended for standardized use in chronic kidney disease (CKD).

Methods

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, CINAHL, Scopus and Web of Science were searched from inception to March 2022, identifying studies that evaluated a clinimetric property (validity, reliability, measurement error and/or responsiveness) of an objectively measured performance-based physical function outcomes using the COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) methodology and Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) based recommendations. Studies with individuals of all ages and of any stage of CKD were included.

Results

In total, 50 studies with 21 315 participants were included. Clinimetric properties were reported for 22 different physical function tests. The short physical performance battery (SPPB), Timed-up-and-go (TUG) test and Sit-to-stand tests (STS-5 and STS-60) had favorable properties to support their use in CKD and should be integrated into routine use. However, the majority of studies were conducted in the hemodialysis population, and very few provided information regarding validity or reliability.

Conclusion

The SPPB demonstrated the highest quality of evidence for reliability, measurement error and construct validity amongst transplant, CKD and dialysis patients. This review is an important step towards standardizing a core outcome set of tools to measure physical function in research and clinical settings for the CKD population.

Reliability and validity of the supine-to-stand test in people with stroke

OBJECTIVE

To investigate the psychometric properties of the supine-to-stand test in people with stroke.

DESIGN

Cross-sectional design.

SUBJECTS

Fifty-two people with stroke (mean (standard deviation) age 63.13 (6.09) years; time post-stroke 93.13 (61.36) months) and 49 healthy older adults (61.90 (7.29) months).

METHODS

Subjects with stroke were recruited from the community dwelling in Hong Kong and  assessed with the supineto- stand test, Fugl-Meyer Motor Assessment, ankle muscle strength test, Berg Balance Scale, limit of stability test, Timed Up-and-Go Test, Six-Minute Walk Test, Chinese version of Activities-specific Balance Confidence scale, Community Integration Measure (CIM-C), and 12-item Short-Form Health Survey (SF-12) in a university-based rehabilitation laboratory.

RESULTS

The supine-to-stand test completion time demonstrated excellent intra-rater, inter-rater and test-retest reliability (intraclass correlation coefficient 0.946-1.000) for the people with stroke. The completion time was significantly negatively correlated with Berg Balance Scale, Six-Minute Walk Test, limit of stability - maximal excursion, and limit of stability - endpoint excursion results (r = -0.391 to -0.507), whereas it was positively correlated with the Timed Up-and-Go test results (r = 0.461). The optimal cut-off supine-to-stand test completion time of 5.25 s is feasible for a clinical measure to distinguish the performance of people with stroke from healthy older adults (area under the curve = 0.852, sensitivity = 81.1%, specificity = 84.0%).

CONCLUSION

The supine-to-stand test is a reliable, sensitive, specific and easy-to-administer clinical test for assessing the supine-to-stand ability of people with stroke.

Sit to stand test and handgrip strength in men and women with post-COVID-19 syndrome without invasive ventilator support: insights from a Brazilian observational study

Two valid tests have been used in patients with post-COVID-19 syndrome (coronavirus disease 2019) due to their fast application, feasibility, and accessible procedures, facilitating data collection in large groups: the 1-minute sit-to-stand test (STS) and handgrip strength (HGS) dynamometry. The present study aimed to: i) assess the STS and HGS in men and women with post-COVID-19 syndrome who did not require invasive ventilator support; ii) correlate STS repetitions and HGS with time since the COVID-19 diagnosis. Six hundred and twenty-two men and women with post-COVID-19 syndrome who did not require invasive ventilatory support performed the STS and HGS tests at the beginning of the rehabilitation process at a Reference Hospital Centre. Women over 55 years presented significantly lower results compared to participants under 55 years. For the HGS, the median ranged from 42 to 48 kg and 70 to 81 kg for the female and male groups, respectively. The correlations of time since COVID-19 diagnosis with STS and HGS ranged from -0.16 to 0.02 (p>0.05) for women and men, respectively.The test results could be used for the initial analysis of normality ranges and comparisons with other populations. Although STS repetitions and HGS presented low and non-significant correlations with time since the COVID-19 diagnosis, some COVID-19 sequelae were not measured, so these data should be interpreted with caution.

A Study of the Reliability, Validity, and Physiological Changes of Sit-to-Stand Tests in People With Heart Failure

PURPOSE

The objective of this study was to describe the psychometric properties and physiological response of the five times sit-to-stand (STST-5) and 60-sec sit-to-stand test (STST-60) in adults with heart failure (HF).

METHODS

People with HF enrolled in a 12-wk exercise rehabilitation program completed two STST-5 and two STST-60 as part of their usual baseline and follow-up assessments. Test-retest reliability, validity, and responsiveness of the two STSTs were described. Results were correlated with the 6-min walk test (6MWT) and timed up and go test (TUGT), and rating of perceived exertion and physiological responses were compared between all tests. Feasibility was also reported according to the presence of adverse events and adherence to the protocol.

RESULTS

Forty-nine adults with HF participated in this study. Intraclass correlation coefficients of the STST-5 and STST-60 were 0.91 (95% CI, 0.78-0.96) and 0.96 (95% CI, 0.93-0.98), respectively. The STST-60 was strongly associated with both the 6MWT ( r = 0.76) and the TUGT ( rs =-0.77). The STST-5 was strongly associated with the TUGT ( rs = 0.79) and moderately associated with the 6MWT ( rs =-0.70). Rating of perceived exertion and lower limb fatigue were greater in the STST-60 than in the 6MWT ( P < .001) or STST-5 ( P < .001). Adverse events occurred in five participants undertaking the STST-60 and one participant undertaking the STST-5.

CONCLUSIONS

The STST-5 and STST-60 are reliable and valid measures of functional exercise capacity in people with HF.

Nutritional status of patients with COVID-19 one year post-ICU stay: a prospective observational study

Objective

Patients discharged from the Intensive Care Unit (ICU) often suffer from physical complaints and poor nutritional intake, which negatively affect nutritional status (NS). Our aim was to describe NS of patients with COVID-19 one year post-ICU stay.

Research Methods & Procedures

Observational study of adult patients with COVID-19 one year post-ICU. NS assessment (nutrient balance, body composition and physical status) was performed. Nutritional intake and nutrition-related complaints were examined. Nutritional requirements were determined with indirect calorimetry and body composition with bio-electrical impedance. Fat-free mass index (FFMI) and fat mass index (FMI) were calculated. Physical status was determined with handgrip strength (HGS), 6-minute walk test, and 1-minute sit to stand test (1MSTST). Descriptive statistics and paired sample t-tests were used for analysis.

Results

We included 48 patients (73% male; median age 60 years [IQR 52;65]). Median weight loss during ICU stay was 13%. One year post-ICU 12% weight was regained. Median BMI was 26 kg/m² and 23% was obese (BMI>30 kg/m² and high FMI). Of the patients, 50% had high FMI and 19% had low FFMI. Median reported nutritional intake was 90% of measured resting energy expenditure. Nutrition-related complaints were seen in 16%. Percentages of normal values reached in physical tests were 92% of HGS, 95% of 6 minute walking distance and 79% of 1MSTST.

Conclusion(s)

Despite almost fully regained weight and good physical recovery in adult patients one year post-ICU stay, NS remained impaired due to elevated FMI, even though reported nutritional intake was below the estimated requirements.

Comparative efficacy of exercise modalities for cardiopulmonary function in hemodialysis patients: A systematic review and network meta-analysis

Background

To provide reliable evidence to exercise rehabilitation therapists and clinicians, we compared and analyzed the effects of different exercise modalities on cardiopulmonary function in hemodialysis patients using Bayesian network meta-analysis.

Methods

PubMed, OVID, Web of Science, Cochrane Library, Embase, Scopus, CINAHL, SPORT Discus, SinoMed, CNKI, Wanfang, and VIP were searched from inception to July 20, 2022. We included randomized controlled trials comparing 12 exercise modalities to improve cardiorespiratory fitness in hemodialysis patients. All statistical analysis was performed using STATA and R.

Result

A total of 82 randomized controlled trials involving 4146 maintenance hemodialysis patients were included in this study. The pair-wise meta-analysis showed that all exercise modalities had a positive effect on all indicators of cardiorespiratory capacity. The network meta-analysis demonstrated that Blood flow restriction training (BFRT), Cycle exercise (CE), Inspiratory muscle training (IMT), Combined aerobic and resistance training (CT), and Aerobic training (AT) were significantly better than usual care for 6-min walkability; Medium intensity continuous training (MICT), CT, CE, and AT were considerably better than usual care for VO₂Peak; body and mind training (MBT) and CT significantly improved SBP compared to usual care; and only MBT was significantly better than usual care for DBP. Both the two-dimensional plot and the radar plot demonstrated that CT had the best combined-effect on each index of cardiorespiratory fitness. Subgroup and sensitivity analyses demonstrated the robustness of the results. The evidence was mainly "low" to "very low" for this network meta-analysis.

Conclusion

There is no one exercise that can achieve the best effect on all of the outcomes. The benefits of MBT in decreasing arterial blood pressure are unsurpassed by other exercise methods. The intervention effect of the CT is better and more stable. Electrical muscle stimulation training (MEST) can be employed in individuals who do not wish to exercise actively but may cause an increase in blood pressure. On the basis of the characteristics of different exercise types, guidelines developers, clinicians, and patients may employ them appropriately.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/#recordDetails.

Cardiopulmonary exercise testing in patients with end-stage kidney disease: principles, methodology and clinical applications of the optimal tool for exercise tolerance evaluation

Chronic kidney disease (CKD), especially end-stage kidney disease (ESKD), is associated with an increased risk for cardiovascular events and all-cause mortality. Exercise intolerance as well as reduced cardiovascular reserve is extremely common in patients with CKD. Cardiopulmonary exercise testing (CPET) is a non-invasive, dynamic technique that provides an integrative evaluation of cardiovascular, pulmonary, neuropsychological and metabolic function during maximal or submaximal exercise, allowing the evaluation of functional reserves of these systems. This assessment is based on the principle that system failure typically occurs when the system is under stress and thus CPET is currently considered to be the gold standard for identifying exercise limitation and differentiating its causes. It has been widely used in several medical fields for risk stratification, clinical evaluation and other applications, but its use in everyday practice for CKD patients is scarce. This article describes the basic principles and methodology of CPET and provides an overview of important studies that utilized CPET in patients with ESKD, in an effort to increase awareness of CPET capabilities among practicing nephrologists.

Effects of a Combined Intradialytic Exercise Training Program and Music on Cardiac Autonomic Nervous System Activity in Hemodialysis Patients

This study aimed to examine the effect of an intradialytic exercise program in combination with music on heart rate variability (HRV) indices and functional capacity in patients on maintenance hemodialysis (HD). Methods: Forty HD patients were randomized to four training groups for six months: the combined music and exercise group (Group A), the exercise group (Group B), the music group (Group C), and the control group (Group D). At baseline and after 6 months, all participants underwent both short- (for 30 min) and long- (for 24 h) term measurements of HRV and functional capacity assessment with a 6 min walking test (6MWT). Patients of groups A and C listened to preferred music. Results: Long-term HRV analysis showed that standard deviation of all normal-to-normal RR intervals (SDNN) and the square root of the mean squared differences of successive RR intervals (rMSSD) were significantly higher at the end of the study in groups A (by 13.2% and 47.3%), B (by 15.1% and 50%), and C (by 9.0% and 30.1%), compared to group D (p < 0.05). Values of rMSSD and percentage of RR intervals differing by more than 50 ms from the preceding RR interval (pNN50) were elevated in groups A (by 35.6% and 142.9%), B (by 36.1% and 75%), and C (by 15.2% and 28.6%), compared to baseline measurements (p < 0.05). Also, pNN50 was increased in group A compared to groups B (by 21.4%), C (by 88.9%), and D (by 142.9%) (p < 0.05). Similar results were noted by short-term HRV analysis. Functional capacity was improved at the end of the 6-month study in groups A (by 20.3% and 25.7%) and B (by 15.8% and 21.1%) compared to groups C and D (p < 0.05). Conclusions: Intradialytic exercise combined with music-listening can improve the functional capacity and cardiac autonomic nervous system activity in hemodialysis patients.

Physical recovery across care pathways up to 12 months after hospitalization for COVID-19: A multicenter prospective cohort study (CO-FLOW)

Backgroud

The sudden COVID-19 pandemic forced quick development of care pathways for patients with different needs. Trajectories of physical recovery in hospitalized patients for COVID-19 following different care pathways are unknown. We aimed to assess trajectories of physical recovery and levels of physical function reached within the different care pathways. Additionally, we assessed differences in physical function across care pathways at follow-up visits.

Methods

This multicenter prospective cohort study of adults who had been hospitalized for COVID-19 was performed in 10 centers, including 7 hospitals (1 academic and 6 regional hospitals) and 3 rehabilitation centers (1 medical rehabilitation center and 2 skilled nursing facilities), located in the Netherlands. Study visits were performed at 3, 6, and 12 months post-hospital discharge and included assessment of cardiorespiratory fitness (6 min walk test [6MWT], 1 min sit-to-stand test [1MSTST]), muscle strength (maximum handgrip strength [HGS]) and mobility (de Morton Mobility Index [DEMMI]).

Findings

We report findings for 582 patients who had been discharged from hospital between March 24, 2020 and June 17, 2021. Patients had a median age of 60·0 years, 68·9% (401/582) were male, 94·6% (561/582) had received oxygen therapy, and 35·2% (205/582) mechanical ventilation. We followed patients across four different rehabilitation settings: no rehabilitation (No-rehab, 19·6% [114/582]), community-based rehabilitation (Com-rehab, 54·1% [315/582]), medical rehabilitation (Med-rehab, 13·7% [80/582]), and rehabilitation in a skilled nursing facility (SNF-rehab, 12·5% [73/582]). Overall, outcomes in 6MWT (14·9 meters [95% CI 7·4 to 22·4]), 1MSTST (2·2 repetitions [1·5 to 2·8]), and HGS (3·5 kg [2·9 to 4·0]) improved significantly (p<0·001) from 3 to 6 months and only HGS from 6 to 12 months (2·5 kg [1·8 to 3·1]; p<0·001). DEMMI scores did not significantly improve over time. At 3 months, percentage of normative values reached in 1MSTST differed significantly (p<0.001) across care pathways, with largest impairments in Med- and SNF-rehab groups. At 12 months these differences were no longer significant, reaching, overall, 90·5% on 6MWD, 75·4% on 1MSTST, and 106·9% on HGS.

Interpretation

Overall, physical function improved after hospitalization for COVID-19, with largest improvement within 6 months post-discharge. Patients with rehabilitation after hospital discharge improved in more than one component of physical function, whereas patients without rehabilitation improved solely in muscle strength. Patients who received rehabilitation, and particularly patients with Med- and SNF-rehab, had more severe impairment in physical function at 3 months, but reached equal levels at 12 months compared to patients without follow-up treatment. Our findings indicate the importance of rehabilitation.

Funding

ZonMw, Rijndam Rehabilitation, Laurens (The Netherlands).

Exercise or physical activity-related adverse events in people receiving peritoneal dialysis: A systematic review

People receiving peritoneal dialysis (PD) may benefit from participation in exercise or physical activity. However, exercise therapy for people receiving PD is not typically included in routine care, in part, due to ongoing uncertainties about risk. The aim of this review was to systematically collate and explore data on adverse events experienced by people receiving PD while undertaking an exercise or physical activity intervention. Searches yielded 25 exercise or physical activity intervention studies involving people receiving PD. Of these 25 studies, 17 studies provided adverse event data and were included in the final review. No serious adverse events (e.g. death, hospitalisation) were found attributable to the intervention. From 50 reported adverse events during the intervention period, 32 were attributable to the exercise or physical activity intervention with most being musculoskeletal (e.g. muscle/joint pain, etc.) followed by fatigue. Most events were mild to moderate in severity and resolved by exercise programme modification, education, rest or medication. The results from this review did not uncover signals of harm for people receiving PD who engage in exercise with risk of adverse events appearing to be low, however, improved adverse events reporting and further interventional studies are required before robust guidelines can be produced.

Physical Activity Capacity Assessment of Patients With Chronic Disease and the 1-Minute Sit to Stand Test: Is There an Interest?

Objective

This study aimed to evaluate the efficacy of the 1-minute Sit to Stand test (1MSTS) to determine physical activity capacities for patients with chronic disease.

Methods

For this cross-sectional study, we studied fifty patients with chronic disease and no beta-blocker treatment. They systematically performed a cardiopulmonary exercise test to determine maximal oxygen uptake (V'O₂max). We considered two groups of patients based on the results of the functional evaluation of exercise performance: (1) No limitation in exercise performance (V'O₂max greater or equal to 80% of the theoretical reference) and (2) limited exercise performance (V'O₂max <80% of the theoretical value). All patients also received an 1MSTS on the same day.

Results

We found 22 (44.0%) patients with normal exercise capacity and 28 (56.0%) patients with limited exercise performance. In this sample, mean 1MSTS repetitions were 27.1 (7.1) and 25.2 (8.7), respectively. There were no significant differences between the two groups for repetition and Borg Scale end test. The correlation between V'O₂max measured during the exercise test and 1MSTS repetitions displayed a positive slope [r = 0.401 (95% CI 0.114–625)].

Conclusion

This study demonstrated a moderate relationship between 1MSTS and V'O₂max for patients with chronic disease. 1MSTS did not permit the precise determination of physical activity capacities in this sample.

Exercise training for adults undergoing maintenance dialysis

BACKGROUND

Dialysis treatments weigh heavily on patients' physical and psychosocial health. Multiple studies have assessed the potential for exercise training to improve outcomes in adults undergoing dialysis. However, uncertainties exist in its relevance and sustainable benefits for patient-important outcomes. This is an update of a review first published in 2011.

OBJECTIVES

To assess the benefits and safety of regular structured exercise training in adults undergoing dialysis on patient-important outcomes including death, cardiovascular events, fatigue, functional capacity, pain, and depression. We also aimed to define the optimal prescription of exercise in adults undergoing dialysis.

SEARCH METHODS

In this update, we conducted a systematic search of the Cochrane Kidney and Transplant Register of Studies up to 23 December 2020. The Register includes studies identified from CENTRAL, MEDLINE, EMBASE, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov as well as kidney-related journals and the proceedings of major kidney conferences.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of any structured exercise programs of eight weeks or more in adults undergoing maintenance dialysis compared to no exercise or sham exercise.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the search results for eligibility, extracted the data and assessed the risk of bias using the Cochrane risk of bias tool. Whenever appropriate, we performed random-effects meta-analyses of the mean difference in outcomes. The primary outcomes were death (any cause), cardiovascular events and fatigue. Secondary outcomes were health-related quality of life (HRQoL), depression, pain, functional capacity, blood pressure, adherence to the exercise program, and intervention-related adverse events.

MAIN RESULTS

We identified 89 studies involving 4291 randomised participants, of which 77 studies (3846 participants) contributed to the meta-analyses. Seven studies included adults undergoing peritoneal dialysis. Fifty-six studies reported aerobic exercise interventions, 21 resistance exercise interventions and 19 combined aerobic and resistance training within the same study arm. The interventions lasted from eight weeks to two years and most often took place thrice weekly during dialysis treatments. A single study reported death and no study reported long-term cardiovascular events. Five studies directly assessed fatigue, 46 reported HRQoL and 16 reported fatigue or pain through their assessment of HRQoL. Thirty-five studies assessed functional capacity, and 21 reported resting peripheral blood pressure. Twelve studies reported adherence to exercise sessions, and nine reported exercise-related adverse events. Overall, the quality of the included studies was low and blinding of the participants was generally not feasible due to the nature of the intervention. Exercise had uncertain effects on death, cardiovascular events, and the mental component of HRQoL due to the very low certainty of evidence. Compared with sham or no exercise, exercise training for two to 12 months may improve fatigue in adults undergoing dialysis, however, a meta-analysis could not be conducted. Any exercise training for two to 12 months may improve the physical component of HRQoL (17 studies, 656 participants: MD 4.12, 95% CI 1.88 to 6.37 points on 100 points-scale; I² = 49%; low certainty evidence). Any exercise training for two to 12 months probably improves depressive symptoms (10 studies, 441 participants: SMD -0.65, 95% CI -1.07 to -0.22; I² = 77%; moderate certainty evidence) and the magnitude of the effect may be greater when maintaining the exercise beyond four months (6 studies, 311 participants: SMD -0.30, 95% CI 0.14 to -0.74; I² = 71%). Any exercise training for three to 12 months may improve pain (15 studies, 872 participants: MD 5.28 95% CI -0.12 to 10.69 points on 100 points-scale; I² = 63%: low certainty evidence) however, the 95% CI indicates that exercise training may make little or no difference in the level of pain. Any exercise training for two to six months probably improves functional capacity as it increased the distance reached during six minutes of walking (19 studies, 827 participants: MD 49.91 metres, 95% CI 37.22 to 62.59; I² = 34%; moderate certainty evidence) and the number of sit-to-stand cycles performed in 30 seconds (MD 2.33 cycles, 95% CI 1.71 to 2.96; moderate certainty evidence). There was insufficient evidence to assess the safety of exercise training for adults undergoing maintenance dialysis. The results were similar for aerobic exercise, resistance exercise, and a combination of both aerobic and resistance exercise.

AUTHORS' CONCLUSIONS

It is uncertain whether exercise training improves death, cardiovascular events, or the mental component of HRQoL in adults undergoing maintenance dialysis. Exercise training probably improves depressive symptoms, particularly when the intervention is maintained beyond four months. Exercise training is also likely to improve functional capacity. Low certainty evidence suggested that exercise training may improve fatigue, the physical component of quality of life, and pain. The safety of exercise training for adults undergoing dialysis remains uncertain.

Telerehabilitation: Future of Phase II Cardiac Rehabilitation: Review of Preliminary Outcomes

In this brief communication, we reported Telehealth Home-Based Cardiac Rehabilitation (CR) program structure and preliminary outcomes from patients that completed a 12-week program after coronary artery bypass graft surgery (CABG). We aim to advocate the use of Telerehabilitation as a Phase II CR in patients immediately after the CABG. This approach was innovative and encouraging because the patients were still in subacute phase. The program can serve as a continuation of care for the patients after being discharged from a hospital while regaining their functional ability at home. Our preliminary outcomes demonstrated improvements in resting heart rate, activity level, nutrition status, self-efficacy for managing cardiac diseases, muscle strength, endurance and depression. There were no adverse events during the virtual sessions. Patient satisfaction score was high.

Sarcopenia in Chronic Kidney Disease: A Scoping Review of Prevalence, Risk Factors, Association with Outcomes, and Treatment

Sarcopenia, a condition characterized by loss of skeletal muscle mass and function, has important clinical ramifications. We aimed to map the existing literature about prevalence, risk factors, associated adverse outcomes, and treatment of sarcopenia in individuals with chronic kidney disease (CKD). A scoping review of the literature was conducted to identify relevant articles published from databases' inception to September 2019. Individuals with CKD, regardless of their disease stage and their comorbidities, were included. Only studies with sarcopenia diagnosed using both muscle mass and function, based on published consensus definitions, were included. For studies on treatment, only randomized controlled trials with at least one sarcopenia parameter as an outcome were included. Our search yielded 1318 articles, of which 60 from were eligible for this review. The prevalence of sarcopenia ranged from 4 to 42% according to the definition used, population studied, and the disease stage. Several risk factors for sarcopenia were identified including age, male gender, low BMI, malnutrition, and high inflammatory status. Sarcopenia was found to be associated with several adverse outcomes, including disabilities, hospitalizations, and mortality. In CKD subjects, several therapeutic interventions have been assessed in randomized controlled trial with a muscle mass, strength, or function endpoint, however, studies focusing on sarcopenic CKD individuals are lacking. The key interventions in the prevention and treatment of sarcopenia in CKD seem to be aerobic and resistance exercises along with nutritional interventions. Whether these interventions are effective to treat sarcopenia and prevent clinical consequences in this population remains to be fully determined.

Cluster Randomized Controlled Trial on the Effects of 12 Months of Combined Exercise Training during Hemodialysis in Patients with Chronic Kidney Disease-Study Protocol of the Dialysis Training Therapy (DiaTT) Trial

Patients with chronic kidney disease (CKD) on hemodialysis (HD) experience treatment-related immobility and physical deconditioning, which is responsible for an increased risk of frailty and a high burden of multi-morbidity. Exercise has been shown to counteract this vicious cycle; however, its effectiveness has only been investigated in small cohorts. Therefore, the objective of the Dialysis Training Therapy (DiaTT) trial will be to assess the effects of a 12-month intradialytic exercise program on physical functioning, frailty and health economics in a large cohort of HD patients in a real-world setting. DiaTT will be a prospective, cluster-randomized (1:1), controlled, multi-center, interventional clinical trial across 28 dialysis units, aiming at the recruitment of >1100 CKD patients on HD. The intervention group will receive 12 months’ intradialytic exercise (combined aerobic and resistance training), whereas the usual care group will not receive intervention. The primary endpoint will be a change on the sit-to-stand test (STS60) result between baseline and 12 months. Secondary endpoints will include physical functioning, frailty, quality of life, 3-point MACE, hospitalizations, survival, quality of HD, health literacy and health care costs. By including almost as many patients as previously investigated in smaller trials, DiaTT will be the largest randomized, controlled trial assessing frailty, quality of life and mortality in the field of nephrology.

CO-FLOW: COvid-19 Follow-up care paths and Long-term Outcomes Within the Dutch health care system: study protocol of a multicenter prospective cohort study following patients 2 years after hospital discharge

BACKGROUND

First studies indicate that up to 6 months after hospital discharge, coronavirus disease 2019 (COVID-19) causes severe physical, cognitive, and psychological impairments, which may affect participation and health-related quality of life (HRQoL). After hospitalization for COVID-19, a number of patients are referred to medical rehabilitation centers or skilled nursing facilities for further treatment, while others go home with or without aftercare. The aftercare paths include 1] community-based rehabilitation; 2] in- and outpatient medical rehabilitation; 3] inpatient rehabilitation in skilled nursing facilities; and 4] sheltered care (inpatient). These aftercare paths and the trajectories of recovery after COVID-19 urgently need long-term in-depth evaluation to optimize and personalize treatment. CO-FLOW aims, by following the outcomes and aftercare paths of all COVID-19 patients after hospital discharge, to systematically study over a 2-year period: 1] trajectories of physical, cognitive, and psychological recovery; 2] patient flows, healthcare utilization, patient satisfaction with aftercare, and barriers/facilitators regarding aftercare as experienced by healthcare professionals; 3] effects of physical, cognitive, and psychological outcomes on participation and HRQoL; and 4] predictors for long-term recovery, health care utilization, and patient satisfaction with aftercare.

METHODS

CO-FLOW is a multicenter prospective cohort study in the mid-west of the Netherlands with a 2-year follow-up period. Measurements comprise non-invasive clinical tests and patient reported outcome measures from a combined rehabilitation, pulmonary, and intensive care perspective. Measurements are performed at 3, 6, 12, and 24 months after hospital discharge and, if applicable, at rehabilitation discharge. CO-FLOW aims to include at least 500 patients who survived hospitalization for COVID-19, aged ≥18 years.

DISCUSSION

CO-FLOW will provide in-depth knowledge on the long-term sequelae of COVID-19 and the quality of current aftercare paths for patients who survived hospitalization. This knowledge is a prerequisite to facilitate the right care in the right place for COVID-19 and comparable future infectious diseases.

TRIAL REGISTRATION

The Netherlands Trial Register (NTR), https://www.trialregister.nl . Registered: 12-06-2020, CO-FLOW trialregister no. NL8710.

Exercise training in dialysis patients: impact on cardiovascular and skeletal muscle health

Dialysis patients show a high rate of reduced functional capacity, morbidity and mortality. Cardiovascular disorders, muscle atrophy and malnutrition play an essential role among the aetiological factors. Sedentary lifestyle characterizes them and contributes to the aggravation of the disorders. On the contrary, exercise training is an important preventive and therapeutic tool both for cardiovascular problems and for the appearance of muscle atrophy in dialysis patients. Regular exercise causes both central (cardiac) and peripheral (muscular) adaptations, improving functional capacity. In particular, circulatory system clinical trials in haemodialysis (HD) patients documented that exercise has favourable effects on heart function, promotes balance on the cardiac autonomic nervous system and contributes to the management of arterial hypertension. In the muscular system, it prevents muscle atrophy or contributes significantly to its treatment. The main preventive mechanisms of the beneficial effect of exercise on the muscles constitute the inhibition of the apoptotic processes and protein degradation. Exercise training in HD patients leads to an increase of muscle fibers, mitochondria and capillaries, and the combination of regular exercise and dietary strategies is even more effective in preventing or treating muscle atrophy. Finally, an improvement in functional capacity and quality of life was found also in peritoneal dialysis patients following exercise training.

Sit-To-Stand Movement Evaluated Using an Inertial Measurement Unit Embedded in Smart Glasses-A Validation Study

Wearable sensors have recently been used to evaluate biomechanical parameters of everyday movements, but few have been located at the head level. This study investigated the relative and absolute reliability (intra- and inter-session) and concurrent validity of an inertial measurement unit (IMU) embedded in smart eyeglasses during sit-to-stand (STS) movements for the measurement of maximal acceleration of the head. Reliability and concurrent validity were investigated in nineteen young and healthy participants by comparing the acceleration values of the glasses’ IMU to an optoelectronic system. Sit-to-stand movements were performed in laboratory conditions using standardized tests. Participants wore the smart glasses and completed two testing sessions with STS movements performed at two speeds (slow and comfortable) under two different conditions (with and without a cervical collar). Both the vertical and anteroposterior acceleration values were collected and analyzed. The use of the cervical collar did not significantly influence the results obtained. The relative reliability intra- and inter-session was good to excellent (i.e., intraclass correlation coefficients were between 0.78 and 0.91) and excellent absolute reliability (i.e., standard error of the measurement lower than 10% of the average test or retest value) was observed for the glasses, especially for the vertical axis. Whatever the testing sessions in all conditions, significant correlations (p < 0.001) were found for the acceleration values recorded either in the vertical axis and in the anteroposterior axis between the glasses and the optoelectronic system. Concurrent validity between the glasses and the optoelectronic system was observed. Our observations indicate that the IMU embedded in smart glasses is accurate to measure vertical acceleration during STS movements. Further studies should investigate the use of these smart glasses to assess the STS movement in unstandardized settings (i.e., clinical and/or home) and to report vertical acceleration values in an elderly population of fallers and non-fallers.

Uremic Sarcopenia: Clinical Evidence and Basic Experimental Approach

Sustained physical activity extends healthy life years while a lower activity due to sarcopenia can reduce them. Sarcopenia is defined as a decrease in skeletal muscle mass and strength due not only to aging, but also from a variety of debilitating chronic illnesses such as cancer and heart failure. Patients with chronic kidney disease (CKD), who tend to be cachexic and in frail health, may develop uremic sarcopenia or uremic myopathy due to an imbalance between muscle protein synthesis and catabolism. Here, we review clinical evidence indicating reduced physical activity as renal function deteriorates and explore evidence-supported therapeutic options focusing on nutrition and physical training. In addition, although sarcopenia is a clinical concept and difficult to recapitulate in basic research, several in vivo approaches have been attempted, such as rodent subtotal nephrectomy representing both renal dysfunction and muscle weakness. This review highlights molecular mechanisms and promising interventions for uremic sarcopenia that were revealed through basic research. Extensive study is still needed to cast light on the many aspects of locomotive organ impairments in CKD and explore the ways that diet and exercise therapies can improve both outcomes and quality of life at every level.

Modifiable Physical Factors Associated With Physical Functioning for Patients Receiving Dialysis: A Systematic Review

Background: Patients receiving dialysis have reduced physical function, which is associated with unfavorable clinical outcomes and decreased quality of life. The authors aimed to identify and explore modifiable physical factors associated with physical function for patients receiving dialysis. Methods: Searches were performed in MEDLINE, Embase, Ovid Emcare, and The Cochrane Library in October 2018. Etiological studies involving dialysis populations that report association or predictive statistics between a modifiable physical factor and physical function were eligible for inclusion. Predictor variables were (1) modifiable via exercise and (2) considered an impairment in the International Classification of Functioning, Disability and Health. Results: Of 5384 titles screened, 23 studies were included. Thirteen studies focused on physical activity levels and muscle strength and the relationship with physical function while 2 studies investigated sedentary behavior. Twenty-one studies focused on hemodialysis populations. Studies related to physical activity levels displayed a moderately strong relationship with physical function, whereas muscle strength displayed a predominantly weak to moderate relationship. Conclusions: Physical activity levels, sedentary behavior levels, and muscle strength are related to physical function status for patients receiving dialysis. There is a need for robust longitudinal data to confirm the results of this investigation and for more focus on populations receiving peritoneal dialysis.

Effects of exercise on residual renal function in patients undergoing peritoneal dialysis: A post-hoc analysis of a randomized controlled trial

We aimed to investigate the effects of exercise on renal outcomes in patients undergoing peritoneal dialysis (PD). In a post-hoc analysis of a randomized controlled trial of a 12-week home-based exercise program involving 47 patients undergoing PD, we excluded 18 patients with anuria and analyzed 13 and 16 patients in the usual care and exercise groups, respectively. The primary outcomes were weekly renal creatinine clearance (CCr) and urinary biomarkers: liver-type fatty acid-binding protein (L-FABP) and the microalbumin-to-creatinine ratio (ACR). Although the maintenance of weekly renal CCr in the exercise group was not significantly different compared with that in the usual care group (P = .09), urinary L-FABP levels (P = .02) and ACR (P = .04) were significantly decreased in the exercise group. To the best of our knowledge, this is the first study to demonstrate the beneficial effects of exercise on renal outcomes in patients undergoing PD.

Intradialytic training in patients with end-stage renal disease: a systematic review and meta-analysis of randomized clinical trials assessing the effects of five different training interventions

OBJECTIVE

Patients with end-stage renal disease (ESRD) undergoing hemodialysis may have reduced dialysis adequacy (Kt/V), low cardiorespiratory fitness, and worse prognosis. Different types of intradialytic training (IDT) may serve as an adjunct therapy for the management of the ESRD. This systematic review and meta-analysis aimed to assess the impact of different types of IDT on clinical outcomes and functional parameters in ESRD.

METHODS

PubMed, Embase, CINAHL, Cochrane CENTRAL, Scopus, SPORTDiscus, and Google Scholar were searched for randomized clinical trials in adult patients with ESRD which compared IDT with usual care (UC), without language restrictions and published up to July 2019; a handsearch of references was also performed. Certainty of evidence was assessed using GRADE, and risk of bias in primary studies with the RoB 1.0 tool.

RESULTS

Fifty studies were included (n = 1757). Compared to UC, aerobic IDT improved Kt/V (WMD = 0.08), VO₂peak (WMD = 2.07 mL/kg/min), 6-minute walk test (6MWT) distance (64.98 m), reduced systolic blood pressure (- 10.07 mmHg) and C-reactive protein (- 3.28 mg/L). Resistance training increased 6MWT distance (68.50 m). Combined training increased VO₂peak (5.41 mL/kg/min) and reduced diastolic blood pressure (- 5.76 mmHg). Functional electrostimulation (FES) and inspiratory muscle training (IMT) improved 6MWT distance (54.14 m and 117.62 m, respectively). There was no impact on total cholesterol, interleukin-6, or hemoglobin levels. There was no difference in incidence of adverse events between the IDT and control groups. The certainty of evidence was variable according to the GRADE scale, with most outcomes rated very low certainty. The risk of bias assessment of primary studies showed unclear risk in most.

CONCLUSIONS

Aerobic, resistance, and combined training during hemodialysis, as well as FES and IMT, demonstrated to be effective for the treatment of the patient with ESRD. Our data should be interpreted in light of the unclear risk of bias of most evaluated articles and the low to very low certainty of evidence for evaluated outcomes.

PROSPERO REGISTRATION ID

CRD42017081338. DATA SHARING REPOSITORY: https://osf.io/fpj54/.

Test-Retest Reliability for Physical Function Measures in Patients with Chronic Kidney Disease

BACKGROUND

It is important to determine relative and absolute reliability values in outcome measures that are used in clinical practice so as to discriminate between true changes following exercise interventions for patients with chronic kidney disease (CKD).

OBJECTIVE

The study aimed to assess test-retest reliability of the incremental shuttle walk test (ISWT), sit-to-stand transfers in 60 seconds (STS-60), timed up and go (TUAG), Duke's activity status index (DASI) and hospital anxiety and depression scale (HAD) in patients with CKD.

STUDY DESIGN

This study was a pragmatic non-randomised controlled trial.

METHODS

Forty people attended two study visits within a 16-day window involving the ISWT, STS-60, TUAG, DASI and HAD tests. Relative reliability was assessed using intraclass correlation coefficient (ICC) and absolute reliability using the standard error of measurement (SEM) and minimal detectable change (MDC).

RESULTS

Good test-retest reliability was found for the entire sample size across all outcome measures, with TUAG having the highest (ICC = 0.96) and HAD the lowest (ICC = 0.71). The MDC scores at 90% confidence interval (CI) were: 79.6 m for the ISWT, 2.9 seconds for the TUAG, 7.0 repetitions for the STS-60, 8.4 for the DASI, 3.8 for the anxiety HAD subscale and 4.4 for the depression HAD subscale.

CONCLUSIONS

This study demonstrated good test-retest reliability for all outcome measures across the CKD trajectory but caution needs to be taken when interpreting the findings for each CKD sub-group separately. The MDC scores at 90% CI can support therapists in determining a true improvement in CKD patients' physical or mental performance.

Effects of intradialytic exercise on cardiopulmonary capacity in chronic kidney disease: systematic review and meta-analysis of randomized clinical trials

Patients with chronic kidney disease show poorer functional and cardiorespiratory capacity than healthy individuals, and these impairments result in sedentarism. The aim of this study was to conduct a systematic review and meta-analysis of randomized clinical trials on the effects of different intradialytic exercise protocols on cardiopulmonary capacity in chronic kidney disease patients. The primary outcome was peak oxygen consumption (VO_2peak) and the secondary outcomes were exercise duration and ventilation in the cardiopulmonary test. The quality of the evidence was evaluated using the GRADE guidelines. Seven studies with a total of 124 participants met the inclusion criteria. Compared to the non-exercise group, the exercise group improved in mean VO_2peak (MD 4.06 [IC 0.81; 7.31]). In a separate analysis according to exercise modality, aerobic exercise plus strength training performed better than aerobic exercise alone (MD 5.28 [IC 3.90; 6.66]). In the exercise group, both exercise tolerance values (MD 3.10 [IC 1.70; 4.51]) and ventilation values in the cardiopulmonary test were better than those of the control group (MD 13.10 [IC 7.12; 19.09]). Thus, intradialytic exercise protocols can improve cardiopulmonary function, exercise tolerance and ventilatory efficiency in chronic kidney disease patients.

Aerobic exercise in adults with chronic kidney disease (CKD): a meta-analysis

PURPOSE

Patients with chronic kidney disease (CKD) are frail and have high risk of cardiovascular disease. This study was performed to assess the effects of aerobic exercise training in adults with CKD.

METHODS

MEDLINE, EMBASE, CENTRAL, Web of Science were searched up to December 2018 to identify eligible randomized controlled trials (RCTs) that studied aerobic exercise in adults with CKD. Primary outcomes include oxygen consumption at peak exercise (VO₂ peak), exercise capacity, blood pressure, heart rate, and health-related quality of life (HRQoL). Statistical analysis was performed using Review Manager 5.2.1 software.

RESULTS

Thirty-one trials, containing 1305 adults with CKD, were included. The most used aerobic exercise program was characterized as moderate intensity (15/31), 3 times/week frequency (22/31), 30 min duration (9/31) and 3 months follow-up (12/31). Significant improvement was observed in cardiorespiratory function (VO₂ peak) (P < 0.0001), exercise duration (P < 0.0001), HDL-C (P = 0.03) and pain (P = 0.007), physical role (P = 0.03), general health (P = 0.007) of HRQoL after aerobic exercise in patients with CKD. A marginal difference was observed in HR max (P = 0.07). However, no statistical difference was noticed in exercise capacity, blood pressure, resting heart rate, serum lipid and serum creatinine between aerobic training group and control. No subgroup differences were altered in all outcomes when studies were divided based on intensity of exercise training, the treatment of dialysis or the length of intervention.

CONCLUSIONS

Aerobic exercise training could benefit adult CKD patients in increasing cardiorespiratory function, exercise duration, HDL-C level and improve health quality of life.

Exercise interventions for improving objective physical function in patients with end-stage kidney disease on dialysis: a systematic review and meta-analysis

Patients with end-stage kidney disease on dialysis have increased mortality and reduced physical activity, contributing to impaired physical function. Although exercise programs have demonstrated a positive effect on physiological outcomes such as cardiovascular function and strength, there is a reduced focus on physical function. The aim of this review was to determine whether exercise programs improve objective measures of physical function indicative of activities of daily living for patients with end-stage kidney disease on dialysis. A systematic search of Medline, Embase, the Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature identified 27 randomized control trials. Only randomized control trials using an exercise intervention or significant muscular activation in the intervention, a usual care, nonexercising control group, and at least one objective measure of physical function were included. Participants were ≥18 yr of age, with end-stage kidney disease, undergoing hemo- or peritoneal dialysis. Systematic review of the literature and quality assessment of the included studies used the Cochrane Collaboration’s tool for assessing risk bias. A meta-analysis was completed for the 6-min walk test. Data from 27 studies with 1,156 participants showed that exercise, regardless of modality, generally increased 6-min walk test distance, sit-to-stand time or repetitions, and grip strength as well as step and stair climb times or repetitions, dynamic mobility, and short physical performance battery scores. From the evidence available, exercise, regardless of modality, improved objective measures of physical function for end-stage kidney disease patients undergoing dialysis. It is acknowledged that further well-designed randomized control trials are required.

Are dialysis patients too frail to exercise?

Clinical manifestations of functional and morphological muscular abnormalities in dialysis patients are muscle weakness and low exercise capacity, possibly leading to a sedentary life style with low physical activity. Low cardiorespiratory fitness and muscle atrophy and weakness contribute to the development of frailty and affect patients' ability to physically navigate their environment. While many dialysis patients may appear too frail to participate in moderate-to-vigorous aerobic exercise training, those who can complete such programs appear to derive substantial benefit. Less vigorous aerobic exercise, resistance training, and alternative forms of exercise can also be beneficial. Most patients on dialysis are not too frail to perform resistance exercise of adequate intensity to achieve increases in muscle size and strength, therefore, frailty should not be considered a contraindication to exercise.

Effects of whole body vibration on cardiac autonomic function and exercise capacity in renal transplant recipients

Background/Aims

Whole body vibration is an exercise alternative that can be used in the rehabilitation of renal transplant recipients with the aim of reducing cardiovascular risk. The aim of this study was to evaluate the effects of whole body vibration training on heart rate variability, cardiorespiratory parameters and functional capacity on five renal transplant recipients.

Methods

Renal transplant recipients underwent whole body vibration exercise twice a week for a total of 12 weeks. All participants were monitored using the 24-hour Holter to evaluate the heart rate variability domains. An exercise test to evaluate maximal oxygen consumption and the distance walked in the Six-Minute Walk Test to evaluate functional capacity were also recorded.

Results

Overall, two of the five transplant recipients improved sympathovagal balance at the end of the study. Maximal oxygen consumption improved in three transplanted patients, and the distance walked improved for two patients. The results showed that whole body vibration training improved heart rate variability and maximal and submaximal test performance in some transplanted recipients.

Conclusion

The 12-week training protocol with twice weekly whole body vibration sessions was sufficient to improve heart rate variability and the performance of maximal and submaximal tests in some renal transplant recipients, although the responses were heterogeneous for the considered variables. Whole body vibration may be an alternative to conventional means of physical exercise because it causes minimal cardiovascular stress, which could be especially indicated for this population given the risk presence of arrhythmias and sudden death; therefore studies with better designs need to be developed in order to verify the effectiveness of this intervention.

Functional sympatholysis is impaired in end-stage renal disease

Patients with end-stage renal disease (ESRD) have decreased exercise capacity and exercise intolerance that contribute to cardiovascular risk. One potential mechanism underlying exercise intolerance in ESRD is impaired ability to oppose sympathetically mediated vasoconstriction within exercising skeletal muscle (i.e., functional sympatholysis, FS). We hypothesized that ESRD patients have impaired FS compared with healthy (CON) and hypertensive (HTN) controls and that impaired FS is related to circulating levels of the uremic toxin asymmetric dimethyl arginine (ADMA), an endogenous nitric oxide synthase inhibitor. Near-infrared spectroscopy-derived oxygen tissue saturation index (TSI) of the forearm muscle was measured continuously in 33 participants (9 CON, 14 HTN, 10 ESRD) at rest and during low-dose (-20 mmHg) lower body negative pressure (LBNP), moderate rhythmic handgrip exercise, and LBNP with concomitant handgrip exercise (LBNP+handgrip). Resting muscle TSI was lower in ESRD than in CON and HTN groups (CON = 67.8 ± 1.9%, HTN = 67.2 ± 1.1%, ESRD = 62.7 ± 1.5%, P = 0.03). Whereas CON and HTN groups had an attenuation in sympathetically mediated reduction in TSI during LBNP + handgrip compared with LBNP alone (P ≤ 0.05), this response was not present in ESRD (P = 0.71), suggesting impaired FS. There was no difference in plasma [ADMA] between groups (CON = 0.47 ± 0.05 µmol/l, HTN = 0.42 ± 0.06 µmol/l, ESRD = 0.63 ± 0.14 µmol/l, P = 0.106) and no correlation between plasma [ADMA] and resting muscle TSI (P = 0.84) or FS (P = 0.75). Collectively, these findings suggest that ESRD patients have lower muscle perfusion at rest and impaired FS but that these derangements are not related to circulating [ADMA].

A pilot study investigating the effect of pedalling exercise during dialysis on 6-min walking test and hand grip and pinch strength

Introduction:

Haemodialysis patients are at an increased risk of sarcopenia. Physical inactivity is now recognised as a major cause of muscle wasting in haemodialysis patients. It is unclear as to what and how much exercise is required to show benefit. We therefore performed a pilot study of cycling during haemodialysis.

Methods:

Patients underwent a progressive submaximal individualised cycling exercise, 3× a week during haemodialysis for 4 months using bed-cycle ergometers. Body composition was measured by multifrequency segmental bioimpedance and muscle function by 6-min walking test, and hand grip strength and pinch strength.

Results:

In total, 56% of patients in a dialysis centre fulfilled exercise study inclusion criteria and 13 (72.2%) of 18 patients completed the exercise programme, with the mean age of 64.0 ± 16.6 years and 76.9% being male. The 6-min walking test increased following exercise from 349 ± 105 to 398 ± 94.2 m, p < 0.05, as did both hand grip strength and pinch strength, with 20.4 ± 9.1 versus 23.4 ± 9.9 kg, p < 0.01, and 4.3 ± 1.8 versus 5.9 ± 2.4 kg, p < 0.05, respectively. There were no changes in appendicular muscle mass or other body composition detected with bioimpedance in either the exercise group, or 21 control patients, propensity matched for body composition, comorbidity and frailty. Muscle strength did not change in the control group. Haemodialysis sessional Kt/Vurea was greater at the end of the exercise programme compared to controls (1.63 ± 0.63 vs 1.21 ± 0.12, p < 0.01).

Conclusion:

The majority of dialysis centre patients met our exercise study entry criteria and could potentially benefit from cycling during haemodialysis. We found that muscle function and strength improved after a 4-month, thrice weekly cycling exercise programme.

1-Minute Sit-to-Stand Test: SYSTEMATIC REVIEW OF PROCEDURES, PERFORMANCE, AND CLINIMETRIC PROPERTIES

PURPOSE

Tests for quantifying exercise capacity that are applicable in diverse settings are needed. The 1-min sit-to-stand test (1-MSTST) is such a test. This systematic review summarizes the literature addressing 1-MSTST procedures, performance, and clinimetric properties.

METHODS

Three online databases, hand searches, and an expert consultant were used to identify literature relevant to the aims of this review. Inclusion required that studies addressed the 1-MSTST, focused on adults, and were written in English.

RESULTS

Seventeen articles were identified that met the inclusion criteria. The populations assessed included adults without identified pathologies and adults with lung disease, renal disease, stroke, osteoporosis, or receiving palliative care. The 1-MSTST typically involves an armless chair and the performance of as many sit-to-stand actions as possible in 1 min without using the upper limbs. The mean number of 1-MSTST repetitions reported in the literature achieved ranged from 8.1 (patients with stroke) to 50.0 (young men). Numerous studies supported the convergent and known-groups validity and the test-retest reliability of the test. The test has been shown to be responsive. Normative reference values are available.

CONCLUSIONS

The literature provides considerable support for using the 1-MSTST to quantify exercise capacity. Broader use of this test may be indicated, particularly where space and time are limited.

Assessment of Fatigue in End Stage Renal Disease Patients Undergoing Hemodialysis: Prevalence and Associated Factors

Background:

Fatigue is a common symptom referred by many patients undergoing hemodialysis. Fatigue is associated with poor health-related quality of life (HRQoL) and is an important predictor for survival of hemodialysis patients.

Aim:

To assess the levels of fatigue and demographic factors affecting it among patients with End Stage Renal Disease undergoing hemodialysis.

Methods:

This quantitative study was carried out in two Dialysis Units of Hospitals in Athens Region. Between January 2015 and June 2015, 129 hemodialysis patients completed the Greek Version of the Fatigue Assessment Scale (FAS). Demographic data of patients was recorded. For the statistical analysis IBM SPSS Statistics version 20 was used.

Results:

The mean FAS score was 24.99. 49 patients (38.0%) were non fatigued, 61 patients (47.3%) were fatigued, and 19 patients (13.7%) were extremely fatigued. Higher levels of fatigue were reported among hemodialysis patients residing in urban areas, in those with low educational level and unemployed.

Conclusion:

The findings of this study can be used in the assessment of fatigue and early identification of high-risk patients (especially of the unemployed, those who occupy with domestic works, those with low educational level and of urban citizens). Use of this knowledge by hemodialysis nurses may lead to a better understanding of the factors of fatigue in ESRD, which in turn may lead to a more effective treatment.

Frailty and chronic kidney disease: current evidence and continuing uncertainties

Frailty, the state of increased vulnerability to physical stressors as a result of progressive and sustained degeneration in multiple physiological systems, is common in those with chronic kidney disease (CKD). In fact, the prevalence of frailty in the older adult population is reported to be 11%, whereas the prevalence of frailty has been reported to be greater than 60% in dialysis-dependent CKD patients. Frailty is independently linked with adverse clinical outcomes in all stages of CKD and has been repeatedly shown to be associated with an increased risk of mortality and hospitalization. In recent years there have been efforts to create an operationalized definition of frailty to aid its diagnosis and to categorize its severity. Two principal concepts are described, namely the Fried Phenotype Model of Physical Frailty and the Cumulative Deficit Model of Frailty. There is no agreement on which frailty assessment approach is superior, therefore, for the time being, emphasis should be placed on any efforts to identify frailty. Recognizing frailty should prompt a holistic assessment of the patient to address risk factors that may exacerbate its progression and to ensure that the patient has appropriate psychological and social support. Adequate nutritional intake is essential and individualized exercise programmes should be offered. The acknowledgement of frailty should prompt discussions that explore the future care wishes of these vulnerable patients. With further study, nephrologists may be able to use frailty assessments to inform discussions with patients about the initiation of renal replacement therapy.

Intradialytic exercise training modalities on physical functioning and health-related quality of life in patients undergoing maintenance hemodialysis: systematic review and meta-analysis

OBJECTIVE

To determine the effects of different intradialytic exercise training modalities on physical functioning and health-related quality of life of maintenance hemodialysis patients.

METHODS

We searched MEDLINE, Cochrane Trials Register and CINAHL for controlled trials that evaluated the effects of intradialytic exercise training for maintenance hemodialysis patients and published from the earliest available date to December 2017. Weighted mean difference and 95% confidence interval (CI) were calculated, and heterogeneity was assessed using the I² test.

RESULTS

Fifty-six studies met the study criteria, comprising a total of 2586 patients. Compared with no exercise, combined aerobic and resistance exercise resulted in significant improvement in peak VO₂ weighted mean difference (5.1 mL kg^-1 min^-1; 95% CI: 3.4, 6.8 mL kg^-1 min^-1), depression symptoms (-7.32; 95% CI -9.31, -5.33) and both physical function (10.67 points; 95% CI 1.08, 20.25 points) and vitality (10.01 points; 95% CI 4.30, 15.72 points) domains of health-related quality of life. Resistance exercise alone was significantly associated with improvement in the 6-minute walk test distance (30.2 m; 95% CI 24.6, 35.9 m), knee extensor strength (0.6 N; 95% CI 0.1, 1.0 N) and Physical Component Score of health-related quality of life (9.53 points; 95% CI -3.09, 22.15 points) when compared with control group. Aerobic exercise alone was not significantly associated with aerobic capacity and quality of life improvement.

CONCLUSION

The results provide support to interventions that combine intradialytic aerobic and resistance exercises to improve physical functioning and quality of life in end-stage renal disease patients undergoing hemodialysis.

Effects of Physical Exercise in Patients with End Stage Renal Failure, on Dialysis and Renal Transplantation: Current Status and Recommendations

There is increasing evidence about the benefits of regular physical activity in the chronically ill. Patients with chronic renal failure prior to and after renal transplant are one of the target groups in which increased controlled physical activity is highly recommended. Significant atrophy and increased non-contractile tissue are present in the muscle of predialytic and patients on hemodialysis, which is associated with poor physical performance and poor outcome of renal disease. Thus, interventions to increase physical activity or otherwise address atrophy may improve performance and quality of life in these patients. Other abnormalities in these patients, such as metabolic impairments, anemia, and hormonal changes, especially insulin resistance and lipid disorders, could be also modulated by certain therapeutic agents and physical activity. Increasing activity levels in this target group could be particularly important since it is well established that controlled physical exercise reduces the risk of cardiovascular disease in the general population. Patients who participate in regular physical activity following transplant will have higher health-related fitness and quality of life compared to those who remain inactive. The potential risk of physical activity can be reduced by medical evaluation, risk stratification, careful supervision, and education

Associations of physical activity energy expenditure with nutritional-inflammatory markers in hemodialysis patients

BACKGROUND

Sedentariness, high inflammation status and malnutrition are highly prevalent in end-stage kidney disease patients on maintenance hemodialysis (MHD). This study investigated associations of weekly physical activity energy expenditure (PAEE) with clinical and anthropometric markers of nutrition and inflammation.

METHODS

The analysis was performed using baseline cross-sectional data of 640 patients enrolled in the prospective cohort "The Prospective Study of the Prognosis of Patients Treated Chronically by Hemodialysis" (PROHEMO) developed in Salvador, BA, Brazil. The long version of the International Physical Activity Questionnaire was used to determine a summary measure of PAEE, the metabolic equivalent of task (MET), taking into account physical activities related to occupation, recreation, travel, sports, and housework. PAEE was the predictor variable. To assess associations of PAEE with outcomes, the sex-age-specific median MET was used. The malnutrition-inflammation score (MIS) with range of 0 to 30 (higher is worse), conicity index as indicator of abdominal adiposity and C-reactive protein (CRP) were the nutritional-inflammatory outcomes.

RESULTS

The mean age of the patients was 48.9 ± 13.8 y, 60.3% were males, 16.7% diabetic, 88.1% nonwhite. In multivariable logistic regression models with adjustments for sociodemographic variables and comorbidities, PAEE ≤median was associated with MIS ≥6 (odds ratio [OR] = 1.57; 95% confidence interval [CI] = 1.08, 2.29), conicity index ≥1.3 (OR = 1.52, 95% CI = 1.03, 2.23) and CRP >1.30 mg/dL (OR = 1.69, 95% CI = 1.08, 2.84).

CONCLUSIONS

Greater physical activity assessed by PAEE was associated with indicators of better nutritional and inflammation status. These results indicate opportunities for improving outcomes in MHD patients by counseling and treatment intervention.

Participant acceptability of exercise in kidney disease (PACE-KD): a feasibility study protocol in renal transplant recipients

INTRODUCTION

Cardiovascular disease (CVD) is a major cause of mortality in renal transplant recipients (RTRs). General population risk scores for CVD underestimate the risk in patients with chronic kidney disease (CKD) suggesting additional non-traditional factors. Renal transplant recipients also exhibit elevated inflammation and impaired immune function. Exercise has a positive impact on these factors in patients with CKD but there is a lack of rigorous research in RTRs, particularly surrounding the feasibility and acceptability of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) in this population. This study aims to explore the feasibility of three different supervised aerobic exercise programmes in RTRs to guide the design of future large-scale efficacy studies.

METHODS AND ANALYSIS

Renal transplant recipients will be randomised to HIIT A (16 min interval training with 4, 2 and 1 min intervals at 80%-90% of peak oxygen uptake (VO_{2 peak})), HIIT B (4×4 min interval training at 80%-90% VO_2peak) or MICT (~40 min cycling at 50%-60% VO_2peak) where they will undertake 24 supervised sessions (approximately thrice weekly over 8 weeks). Assessment visits will be at baseline, midtraining, immediate post-training and 3 months post-training. The study will evaluate the feasibility of recruitment, randomisation, retention, assessment procedures and the implementation of the interventions. A further qualitative sub-study QPACE-KD (Qualitative Participant Acceptability of Exercise in Kidney Disease) will explore patient experiences and perspectives through semistructured interviews and focus groups.

ETHICS AND DISSEMINATION

All required ethical and regulatory approvals have been obtained. Findings will be disseminated through conference presentations, public platforms and academic publications.

TRIAL REGISTRATION NUMBER

Prospectively registered; ISRCTN17122775.

Exercise Training in Elderly People Undergoing Hemodialysis: A Systematic Review and Meta-analysis

Introduction

Previous reviews have indicated the effectiveness of exercise in people undergoing hemodialysis. However, these analyses did not take into account whether the subjects were elderly. We performed a systematic review of the effects of exercise training in elderly people undergoing hemodialysis and updated the evidence of exercise for people undergoing hemodialysis by adding recent research data.

Methods

We searched 8 electronic databases up to June 2016. Inclusion criteria were as follows: randomized controlled trial, English publication, subjects aged 18 and older undergoing hemodialysis, evaluation of physical function as an outcome of exercise intervention. We defined elderly as age 60 years and older. The main outcomes were exercise tolerance (peak/maximum oxygen consumption) and walking ability (6-minute walk distance). Secondary outcomes were lower extremity muscle strength and quality of life.

Results

After screening of 10,923 references, 30 comparisons were entered into the analysis. However, because we found only 1 study in which elderly subjects were treated, we could not perform a meta-analysis for these people. For the general population undergoing hemodialysis, supervised exercise training was shown to significantly increase peak/maximum oxygen consumption (standard mean difference, 0.62; 95% confidence interval 0.38-0.87; P < 0.001), 6-minute walk distance (standard mean difference, 0.58; 95% confidence interval 0.24-0.93; P < 0.001), lower extremity muscle strength (standard mean difference, 0.94; 95% confidence interval 0.67-1.21; P < 0.001), and quality of life (standard mean difference, 0.53; 95% confidence interval 0.52-0.82; P < 0.001).

Discussion

Our analysis on the effectiveness of exercise training in elderly people undergoing hemodialysis as compared with nonelderly people was somewhat inconclusive. Future studies should be carried out for elderly people to identify the most favorable exercise program for this population.

Physical activity, immune function and inflammation in kidney patients (the PINK study): a feasibility trial protocol

INTRODUCTION

Patients with chronic kidney disease (CKD) display increased infection-related mortality and elevated cardiovascular risk only partly attributed to traditional risk factors. Patients with CKD also exhibit a pro-inflammatory environment and impaired immune function. Aerobic exercise has the potential to positively impact these detriments, but is under-researched in this patient population. This feasibility study will investigate the effects of acute aerobic exercise on inflammation and immune function in patients with CKD to inform the design of larger studies intended to ultimately influence current exercise recommendations.

METHODS AND ANALYSIS

Patients with CKD, including renal transplant recipients, will visit the laboratory on two occasions, both preceded by appropriate exercise, alcohol and caffeine restrictions. On visit 1, baseline assessments will be completed, comprising anthropometrics, body composition, cardiovascular function and fatigue and leisure time exercise questionnaires. Participants will then undertake an incremental shuttle walk test to estimate predicted peak O2 consumption (VO2peak). On visit 2, participants will complete a 20 min shuttle walk at a constant speed to achieve 85% estimated VO2peak. Blood and saliva samples will be taken before, immediately after and 1 hour after this exercise bout. Muscle O2 saturation will be monitored throughout exercise and recovery. Age and sex-matched non-CKD 'healthy control' participants will complete an identical protocol. Blood and saliva samples will be analysed for markers of inflammation and immune function, using cytometric bead array and flow cytometry techniques. Appropriate statistical tests will be used to analyse the data.

ETHICS AND DISSEMINATION

A favourable opinion was granted by the East Midlands-Derby Research Ethics Committee on 18 September 2015 (ref 15/EM/0391), and the study was approved and sponsored by University Hospitals of Leicester Research and Innovation (ref 11444). The study was registered with ISRCTN (ref 38935454). The results will be presented at relevant conferences, and it is anticipated that the reports will be published in appropriate journals in 2018.