Resistance training in hemodialysis patients: a review

Preoperative assessment for vascular access: Vascular mapping and handgrip strength

BACKGROUND

Reliable vascular access (VA) is required for patients receiving chronic hemodialysis (HD) treatment. Vascular mapping using duplex doppler ultrasonography (DUS) can aid in planning VA construction. Greater handgrip strength (HGS) was found to be associated with more developed distal vessels both in chronic kidney disease (CKD) patients and healthy individuals, and patients with lower HGS had worse morphologic vessel characteristics and were, therefore, less likely to construct distal VA.

OBJECTIVES

This study aims to describe and analyze clinical, anthropometric, and laboratory characteristics of patients who underwent vascular mapping prior to VA creation.

RESEARCH DESIGN

Prospective analysis.

SUBJECTS

Adult patients with CKD referred for vascular mapping, at a tertiary center, between March 2021 and August 2021.

MEASURES

Preoperative DUS by a single experienced nephrologist was carried out. HGS was measured using a hand dynamometer, and PAD was defined as ABI < 0.9. Sub-groups were analyzed according to distal vasculature size (<2 mm).

RESULTS

A total of 80 patients were included, with a mean age of 65.7 ± 14.7 years; 67.5% were male, and 51.3% were on renal replacement therapy (RRT). Twelve (15%) participants had PAD. HGS was higher in the dominant arm (20.5 ± 12.0 vs 18.8 ± 11.2 kg). Fifty-eight (72.5%) patients had vessels smaller than 2 mm in diameter. There were no significant differences between groups concerning demographics or comorbidities (diabetes, HTN, PAD). HGS was significantly higher in patients with distal vasculature greater than or equal to 2 mm in diameter (dominant arm: 26.1 ± 15.5 vs 18.4 ± 9.7 kg, p = 0.010; non-dominant arm: 24.1 ± 15.3 vs 16.8 ± 8.6, p = 0.008).

CONCLUSIONS

Higher HGS was associated with more developed distal cephalic vein and radial artery. Low HGS might be an indirect sign of suboptimal vascular characteristics, which might help predict the outcomes of VA creation and maturation.

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.

Quasi-cluster randomized trial of a six-month low-intensity group-based resistance exercise for hemodialysis patients on depression and cognitive function: a 12-month follow-up

Objective

This study aimed to examine the effects of a six-month group-based low-intensity resistance exercise program on depression and the cognitive function of hemodialysis patients.

Method

We conducted a quasi-cluster randomized, open-label controlled study from October 2017 to December 2018. Forty-two patients undergoing hemodialysis completed the trial over six months; half participated in the resistance exercise group (n = 21, mean = 74.90 years of age, SD = 2.23, 66.67% female) and the other half were in a stretching control group (n = 21, mean = 72.57 years of age, SD = 2.26, 28.57% female). Depressive symptoms and cognitive function were the primary outcome measures. Behavioral and psychological problems associated with cognitive decline (NPI-Q), subjective insomnia, and exercise self-efficacy were secondary outcomes. Outcomes were measured at baseline, three-month (mid-intervention), six-month (end of intervention), and 12-month (six months after intervention) follow-ups. Linear mixed model analyses were used to determine short-term (immediately after intervention) and long-term (six months after intervention) effects.

Results

In depression, cognitive function, and the NPI-Q, there were no significant effects. In subjective insomnia, a short-term group-by-time interaction in the intervention group compared to the control group was found (ES = .43). However, the effect had disappeared by the 12-month follow-up. In exercise self-efficacy, short- and long-term group-by-time interactions were found. A significant short-term increase in the resistance exercise and a significant decrease in the stretching control was observed (ES = -.83). However, the effect was weakened in the long term (ES = -.38).

Conclusion

The results showed that low-intensity group resistance exercise would reduce subjective insomnia and improve exercise self-efficacy, but the effect was not maintained by six months after the program.

Trial registration: This study was registered on the University Hospital Medical Information Network Clinical Trials Registry (UMIN000029372).

Trial registration:UMIN Japan identifier: UMIN000029372.

Exercise training during hemodialysis in Brazil: A national survey

To evaluate the availability and characteristics of exercise training during hemodialysis in Brazil and to identify the reported barriers to exercise program implementation and maintenance. All dialysis units were assessed for eligibility using the database of the Brazilian Society of Nephrology. Each dialysis unit was contacted by telephone and the questions were administered. In dialysis units with exercise training, questions related to personnel involved, exercise components, and program delivery were included. Additionally, the barriers to exercise program implementation and maintenance were evaluated. This study included 261 dialysis units that responded to the survey. Forty-one dialysis units reported exercise training during hemodialysis in Brazil (prevalence of 15.7%). We identified 66 physiotherapists and 10 exercise physiologists in dialysis units with exercise training. Resistance training was the most common program component (92.7%). Hypotension (90.5%) and muscle cramps (85.7%) were the most common adverse events reported. In dialysis units with exercise training, poor patients' adherence to exercise was the most commonly reported barrier. The most prevalent barrier in dialysis units that tried or never tried to implement the exercise programs was a lack of resources. The number of dialysis units that have exercise training during hemodialysis in Brazil is low, and the most common program component is resistance training. A lack of resources was the most prevalent barrier in dialysis units that tried or never tried to implement the exercise programs.

An Exercise Program for Peritoneal Dialysis Patients in the United States: A Feasibility Study

BACKGROUND

People with end-stage kidney disease receiving peritoneal dialysis (PD) are generally physically inactive and frail. Exercise studies in PD are scarce and currently there are no PD exercise programs in the United States. The primary objective of this study was to test the feasibility of a combined resistance and cardiovascular exercise program for PD patients under the care of a dedicated home dialysis center in the United States.

STUDY DESIGN

Parallel randomized controlled feasibility study.

SETTING & PARTICIPANTS

PD patients were recruited from a single center and randomly assigned to the intervention (exercise; n = 18) or control (nonexercise; n = 18) group.

INTERVENTION

The intervention group received monthly exercise physiologist consultation, exercise prescription (resistance and aerobic exercise program using exercise bands), and 4 exercise support telephone calls over 12 weeks. The control group received standard care.

OUTCOMES

The primary outcome was study feasibility as measured by eligibility rates, recruitment rates, retention rates, adherence rates, adverse events, and sustained exercise rates. Secondary outcome measures were changes in physical function (sit-to-stand test, timed-up-and-go test, and pinch-strength tests) and patient-reported outcome measures.

RESULTS

From a single center with 75 PD patients, 57 (76%) were deemed eligible, resulting in a recruitment rate of 36 (63%) patients. Participants were randomly assigned into 2 groups of 18 (1:1). 10 patients discontinued the study (5 in each arm), resulting in 26 (72%) patients, 13 in each arm, completing the study. 10 of 13 (77%) intervention patients were adherent to the exercise program. A t test analysis of covariance found a difference between the treatment groups for the timed-up-and-go test (P = 0.04) and appetite (P = 0.04). No serious adverse events caused by the exercise program were reported.

LIMITATIONS

Single center, no blinded assessors.

CONCLUSIONS

A resistance and cardiovascular exercise program appears feasible and safe for PD patients. We recommend that providers of PD therapy consider including exercise programs coordinated by exercise professionals to reduce the physical deterioration of PD patients.

FUNDING

None.

TRIAL REGISTRATION

NCT03980795.

Resistance Training for Older Adults: Position Statement From the National Strength and Conditioning Association

Fragala, MS, Cadore, EL, Dorgo, S, Izquierdo, M, Kraemer, WJ, Peterson, MD, and Ryan, ED. Resistance training for older adults: position statement from the national strength and conditioning association. J Strength Cond Res 33(8): 2019-2052, 2019-Aging, even in the absence of chronic disease, is associated with a variety of biological changes that can contribute to decreases in skeletal muscle mass, strength, and function. Such losses decrease physiologic resilience and increase vulnerability to catastrophic events. As such, strategies for both prevention and treatment are necessary for the health and well-being of older adults. The purpose of this Position Statement is to provide an overview of the current and relevant literature and provide evidence-based recommendations for resistance training for older adults. As presented in this Position Statement, current research has demonstrated that countering muscle disuse through resistance training is a powerful intervention to combat the loss of muscle strength and muscle mass, physiological vulnerability, and their debilitating consequences on physical functioning, mobility, independence, chronic disease management, psychological well-being, quality of life, and healthy life expectancy. This Position Statement provides evidence to support recommendations for successful resistance training in older adults related to 4 parts: (a) program design variables, (b) physiological adaptations, (c) functional benefits, and (d) considerations for frailty, sarcopenia, and other chronic conditions. The goal of this Position Statement is to a) help foster a more unified and holistic approach to resistance training for older adults, b) promote the health and functional benefits of resistance training for older adults, and c) prevent or minimize fears and other barriers to implementation of resistance training programs for older adults.

Dietary Protein and Physical Activity Interventions to Support Muscle Maintenance in End-Stage Renal Disease Patients on Hemodialysis

End-stage renal disease patients have insufficient renal clearance capacity left to adequately excrete metabolic waste products. Hemodialysis (HD) is often employed to partially replace renal clearance in these patients. However, skeletal muscle mass and strength start to decline at an accelerated rate after initiation of chronic HD therapy. An essential anabolic stimulus to allow muscle maintenance is dietary protein ingestion. Chronic HD patients generally fail to achieve recommended protein intake levels, in particular on dialysis days. Besides a low protein intake on dialysis days, the protein equivalent of a meal is extracted from the circulation during HD. Apart from protein ingestion, physical activity is essential to allow muscle maintenance. Unfortunately, most chronic HD patients have a sedentary lifestyle. Yet, physical activity and nutritional interventions to support muscle maintenance are generally not implemented in routine patient care. To support muscle maintenance in chronic HD patients, quantity and timing of protein intake should be optimized, in particular throughout dialysis days. Furthermore, implementing physical activity either during or between HD sessions may improve the muscle protein synthetic response to protein ingestion. A well-orchestrated combination of physical activity and nutritional interventions will be instrumental to preserve muscle mass in chronic HD patients.

Effects of intradialytic resistance exercise on systemic inflammation in maintenance hemodialysis patients with sarcopenia: a randomized controlled trial

PURPOSE

To investigate the effect of intradialytic resistance exercise on inflammation markers and sarcopenia indices in maintenance hemodialysis (MHD) patients with sarcopenia.

METHODS

Forty-one MHD patients with sarcopenia were divided into an intervention group (group E, n = 21) and a control group (group C, n = 20). Group C patients only received routine hemodialysis care, whereas group E patients received progressive intradialytic resistance exercise with high or moderate intensity for 12 weeks at three times per week (using the weight of the lower limbs and elastic ball movement of the upper limb) on the basis of routine hemodialysis care.

RESULTS

After 12 weeks, a significant difference in physical activity status (maximum grip strength, daily pace, and physical activity level), Kt/V, and C-reactive protein was found between groups E and C. Inflammatory factors (interleukin (IL)-6, IL-10, and tumor necrosis factor(TNF)-α) increased or decreased more significantly in group E than in group C.

CONCLUSIONS

This study showed that intradialytic resistance exercise can improve physical activity effectively and reduce microinflammatory reactions even if this simple exercise does not affect the muscle mass in MHD patients with sarcopenia.

Intradialytic resistance training: an effective and easy-to-execute strategy

Chronic kidney disease (CKD) alters the morphology and function of skeletal muscles, thereby decreasing patient physical capacity (PC) and quality of life (QoL). Intradialytic resistance training (IRT) is a pragmatic tool used to attenuate these complications. However, IRT has not been strongly adopted in nephrology care centers. This study aimed to assess the efficacy and safety of a low-cost, easy-to-use IRT protocol.

METHODS

The study enrolled 43 patients (52.8 ± 13.85 years) on HD for five to 300 months followed from April 2014 to July 2017. The efficacy of IRT was assessed based on PC - derived from muscle strength (MS) and preferred walking speed (PWS) - and QoL. The occurrence of adverse events was used as a measure of safety. The IRT protocol consisted of exercises of moderate to high intensity for the main muscle groups performed three times a week.

RESULTS

The mean follow-up time was 9.3 ± 3.24 months, for a total of 4,374 sessions of IRT. Compliance to the protocol was 96.5 ± 2.90%, and patients presented significant improvements in MS (from 27.3 ± 11.58 Kgf to 34.8 ± 10.77 Kgf) and PWS (from 0.99 ± 0.29 m/s to 1.26 ± 0.22 m/s). Physical and emotional components of QoL also increased significantly.

CONCLUSION

IRT led to significant increases in PC and higher scores in all domains of QoL. Important adverse events were not observed during intradialytic resistance training.

Physical activity promotion for patients transitioning to dialysis using the "Exercise is Medicine" framework: a multi-center randomized pragmatic trial (EIM-CKD trial) protocol

BACKGROUND

Patients on dialysis are physically inactive, with most reporting activity levels below the fifth percentile of healthy age-matched groups. Several small studies have reported efficacy of diverse exercise interventions among persons with CKD and those on dialysis. However, no single intervention has been widely adopted in real-world practice, despite a clear need in this vulnerable population with high rates of mortality, frailty, and skilled nursing hospitalizations.

METHODS/DESIGN

We describe a pragmatic clinical trial for an exercise intervention among patients transitioning to dialysis. We will use an existing framework - Exercise is Medicine (EIM) - developed by the American College of Sports Medicine. After undertaking formative qualitative research to tailor the EIM framework to the advanced CKD population (eGFR < 30 ml/min/1.73m2), we will randomize 96 patients from two regions-Atlanta and Bay Area-in two intervention arms with incremental levels of clinical-community integration: physical activity assessment during Nephrology clinical visit, brief counseling at pre-dialysis education, and physical activity wearable (group 1) versus group 1 intervention components plus a referral to a free, EIM practitioner-led group exercise program over 16 weeks (group 2; 8 week core intervention; 8-week follow up). We will assess efficacy by comparing between group differences in minutes/week of objectively measured moderate intensity physical activity. To evaluate implementation, we will use questionnaires for assessing barriers to referral, participation and retention along the path of the intervention. Further we will have a plan for dissemination of the intervention by partnering with relevant stakeholders.

DISCUSSION

The overall goal is to inform the development of a practical, cost-conscious intervention "package" that addresses barriers and challenges to physical activity commonly faced by patients with advanced CKD and can be disseminated amongst interested practices.

TRIAL REGISTRATION

ClinicalTrials.gov identifier (Dated:10/17/2017): NCT03311763 .