Home-based exercise for people living with frailty and chronic kidney disease: A mixed-methods pilot randomised controlled trial

Frailty in Kidney Disease: A Comprehensive Review to Advance Its Clinical and Research Applications

Frailty is a multi-system syndrome of decreased physiologic reserve that has been shown to strongly and independently predict morbidity and mortality. Frailty is prevalent in patients living with kidney disease and occurs earlier in individuals with kidney disease as compared to the general population. In this comprehensive review, we aim to advance the clinical and research applications of frailty in kidney disease populations. Specifically, we clarify the definition of frailty and address its common misconceptions; review the mechanisms and epidemiology of frailty in kidney disease; discuss challenges and limitations in frailty measurement; and provide updated evidence related to risk factors for frailty, its associated adverse outcomes, and interventions. We further add to the literature in this topic by highlighting potential applications of frailty measurement in care of patients with kidney disease and conclude with our recommendations for future research related to this important syndrome.

Narrative Review: Clinical Implications and Assessment of Frailty in Patients With Advanced CKD

Frailty is a multidimensional clinical syndrome characterized by low physical activity, reduced strength, accumulation of multiorgan deficits, decreased physiological reserve, and vulnerability to stressors. Frailty has key social, psychological, and cognitive implications. Frailty is accelerated by uremia, leading to a high prevalence of frailty in patients with advanced chronic kidney disease (CKD) and end-stage kidney disease (ESKD) as well as contributing to adverse outcomes in this patient population. Frailty assessment is not routine in patients with CKD; however, a number of validated clinical assessment tools can assist in prognostication. Frailty assessment in nephrology populations supports shared decision-making and advanced communication and should inform key medical transitions. Frailty screening and interventions in CKD or ESKD are a developing research priority with a rapidly expanding literature base.

Physical exercise in kidney disease: A commonly undervalued treatment modality

BACKGROUND

Physical inactivity has been identified as a risk factor for multiple disorders and a strong association exists between chronic kidney disease (CKD) and a sedentary lifestyle. Even though physical activity is crucial in the development and progression of disease, the general focus of the current medical practice is the pharmacological perspective of diseases with inadequate emphasis on lifestyle intervention.

METHODS

In this narrative review we explain the pathophysiological mechanisms underlying the beneficial effects of physical exercise on CKD in addition to discussing the clinical studies and trials centred on physical exercise in patients with CKD.

RESULTS

Physical activity influences several pathophysiological mechanisms including inflammation, oxidative stress, vascular function, immune response and macromolecular metabolism. While exercise can initially induce stress responses like inflammation and oxidative stress, long-term physical activity leads to protective countermeasures and overall improved health. Trials in pre-dialysis CKD patients show that exercise can lead to reductions in body weight, inflammation markers and fasting plasma glucose. Furthermore, it improves patients' functional capacity, cardiorespiratory fitness and quality of life. The effects of exercise on kidney function have been inconsistent in these trials. In haemodialysis, peritoneal dialysis and kidney transplant patients exercise interventions improve cardiorespiratory fitness, walking capacity and quality of life. Combined training shows the best performance to increase peak oxygen uptake in haemodialysis patients. In kidney transplant recipients, exercise improves walking performance, quality of life and potentially arterial stiffness. However, exercise does not affect glucose metabolism, serum cholesterol and inflammation biomarkers. Long-term, adequately powered trials are needed to determine the long-term feasibility, and effects on quality of life and major clinical outcomes, including mortality and cardiovascular risk, in all CKD stages and particularly in kidney transplant patients, a scarcely investigated population.

CONCLUSION

Physical exercise plays a crucial role in ameliorating inflammation, oxidative stress, vascular function, immune response and macromolecular metabolism, and contributes significantly to the quality of life for patients with CKD, irrespective of the treatment and stage. Its direct impact on kidney function remains uncertain. Further extensive, long-term trials to conclusively determine the effect of exercise on major clinical outcomes such as mortality and cardiovascular risk remain a research priority.

Examining the safety and effectiveness of a 4-week supervised exercise intervention in the treatment of frailty in patients with chronic kidney disease

Background

The optimal duration of antifrailty interventions and how best to deliver them to patients with chronic kidney disease (CKD) is unknown. The aim of this study was to examine the safety, feasibility and preliminary efficacy of a 4-week supervised exercise intervention on frailty in patients with CKD.

Methods

We conducted a prospective feasibility study involving patients with ≥stage 3 CKD (1 patient with stage 3 CKD, 7 patients with stage 4 CKD and 17 patients with stage 5 CKD) who were either frail or prefrail according to the physical frailty phenotype and/or had a Short Physical Performance Battery (SPPB) score ≤10. The exercise intervention consisted of two supervised outpatient sessions per week for 4 weeks (eight total sessions). Frailty and other study measures were assessed at baseline and after 4 weeks of exercise.

Results

Of the 34 participants who completed the baseline assessment and were included in the analyses, 25 (73.5%) completed the 4-week assessment. Overall, 64.0% of patients were on dialysis and 64.0% had diabetes mellitus. After 4 weeks of exercise, frailty prevalence, total SPPB scores and energy/fatigue scores improved. No adverse study-related outcomes were reported.

Conclusions

The 4 weeks of supervised exercise was safe, was associated with an excellent completion rate and improved frailty parameters in CKD patients with CKD. This study provides important preliminary data for a future larger prospective randomized study.

Clinical Trialgov

registration: NCT03535584.

Delivering Personalized, Goal-Directed Care to Older Patients Receiving Peritoneal Dialysis

Background

An aging population living with chronic kidney disease and progressing to kidney failure, subsequently receiving peritoneal dialysis (PD) is growing. A significant proportion of these patients are also living with multi-morbidities and some degree of frailty. Recent practice recommendations from the International Society of Peritoneal Dialysis advocate for high-quality, goal-directed PD prescription, and the Standardized Outcomes of Nephrology-PD initiative emphasized the need for an individualized, goal-based care approach in all patients receiving PD treatment. In older patients, this approach to PD care is even more important. A frailty screening assessment, followed by a comprehensive geriatric assessment (CGA) prior to PD initiation and when dictated by change in relevant circumstances is paramount in tailoring PD care and prescription according to the needs, life goals, as well as clinical status of older patients with kidney failure.

Summary

Our review aimed to summarize the different dimensions to be taken into account when delivering PD care to the older patient - from frailty screening and CGA in older patients receiving PD to employing a personalized, goal-directed PD prescription strategy, to preserving residual kidney function, optimizing blood pressure (BP) control, and managing anemia, to addressing symptom burden, to managing nutritional intake and promoting physical exercise, and to explore telehealth opportunities for the older PD population.

Key Messages

What matters most to older PD patients may not be simply extending survival, but more importantly, to be living comfortably on PD treatment with minimal symptom burden in a home environment and to minimize treatment complications.

Use of frailty assessment instruments in nephrology populations: a scoping review

BACKGROUND

Frailty is a clinical syndrome of accelerated aging associated with adverse outcomes. Frailty is prevalent among patients with chronic kidney disease but is infrequently assessed in clinical settings, due to lack of consensus regarding frailty definitions and diagnostic tools. This study aimed to review the practice of frailty assessment in nephrology populations and evaluate the context and timing of frailty assessment.

METHODS

The search included published reports of frailty assessment in patients with chronic kidney disease, undergoing dialysis or in receipt of a kidney transplant, published between January 2000 and November 2021. Medline, CINAHL, Embase, PsychINFO, PubMed and Cochrane Library databases were examined. A total of 164 articles were included for review.

RESULTS

We found that studies were most frequently set within developed nations. Overall, 161 studies were frailty assessments conducted as part of an observational study design, and 3 within an interventional study. Studies favoured assessment of participants with chronic kidney disease (CKD) and transplant candidates. A total of 40 different frailty metrics were used. The most frequently utilised tool was the Fried frailty phenotype. Frailty prevalence varied across populations and research settings from 2.8% among participants with CKD to 82% among patients undergoing haemodialysis. Studies of frailty in conservatively managed populations were infrequent (N = 4). We verified that frailty predicts higher rates of adverse patient outcomes. There is sufficient literature to justify future meta-analyses.

CONCLUSIONS

There is increasing recognition of frailty in nephrology populations and the value of assessment in informing prognostication and decision-making during transitions in care. The Fried frailty phenotype is the most frequently utilised assessment, reflecting the feasibility of incorporating objective measures of frailty and vulnerability into nephrology clinical assessment. Further research examining frailty in low and middle income countries as well as first nations people is required. Future work should focus on interventional strategies exploring frailty rehabilitation.

Frailty in kidney transplant candidates and recipients: pathogenesis and intervention strategies

ABSTRACT

With the rapid aging of the global population posing a serious problem, frailty, a non-specific state that reflects physiological senescence rather than aging in time, has become more widely addressed by researchers in various medical fields. A high prevalence of frailty is found among kidney transplant (KT) candidates and recipients. Therefore, their frailty has become a research hotspot in the field of transplantation. However, current studies mainly focus on the cross-sectional survey of the incidence of frailty among KT candidates and recipients and the relationship between frailty and transplantation. Research on the pathogenesis and intervention is scattered, and relevant review literature is scarce. Exploring the pathogenesis of frailty in KT candidates and recipients and determining effective intervention measures may reduce waiting list mortality and improve the long-term quality of life of KT recipients. Therefore, this review explains the pathogenesis and intervention measures for frailty in KT candidates and recipients to provide a reference for the formulation of effective intervention strategies.

Frailty assessment as part of transplant listing: yes, no or maybe?

Frailty, characterized by a decreased physiological reserve and an increased vulnerability to stressors, is common among kidney transplant (KT) candidates and recipients. In this review, we present and summarize the key arguments for and against the assessment of frailty as part of KT evaluation. The key arguments for including frailty were: (i) sheer prevalence and far-reaching consequences of frailty on KT, and (ii) the ability to conduct a more holistic and objective evaluation of candidates, removing the inaccuracy associated with 'eye-ball' assessments of transplant fitness. The key argument against were: (i) lack of agreement on the definition of frailty and which tools should be used in renal populations, (ii) a lack of clarity on how, by whom and how often frailty assessments should be performed, and (iii) a poor understanding of how acute stressors affect frailty. However, it is the overwhelming opinion that the time has come for frailty assessments to be incorporated into KT listing. Although ongoing areas of uncertainty exist and further evidence development is needed, the well-established impact of frailty on clinical and experiential outcomes, the invaluable information obtained from frailty assessments, and the potential for intervention outweigh these limitations. Proactive and early identification of frailty allows for individualized and improved risk assessment, communication and optimization of candidates.

Wearables in Nephrology: Fanciful Gadgetry or Prêt-à-Porter?

Telemedicine and digitalised healthcare have recently seen exponential growth, led, in part, by increasing efforts to improve patient flexibility and autonomy, as well as drivers from financial austerity and concerns over climate change. Nephrology is no exception, and daily innovations are underway to provide digitalised alternatives to current models of healthcare provision. Wearable technology already exists commercially, and advances in nanotechnology and miniaturisation mean interest is also garnering clinically. Here, we outline the current existing wearable technology pertaining to the diagnosis and monitoring of patients with a spectrum of kidney disease, give an overview of wearable dialysis technology, and explore wearables that do not yet exist but would be of great interest. Finally, we discuss challenges and potential pitfalls with utilising wearable technology and the factors associated with successful implementation.

Outcomes and care priorities for older people living with frailty and advanced chronic kidney disease: a multi-professional scoping review

The growing older population with advanced chronic kidney disease (ACKD stages 4-5) poses a challenge for healthcare worldwide. The high prevalence of frailty and associated adverse health outcomes highlights concerns for management and interventions specific to this population. The aim was to objectively review the evidence relating to older people (≥65 years) living with frailty and ACKD. More specifically how frailty is identified, what interventions have been studied and what outcomes have been reported including outcomes important to patients, families and carers. A scoping review was undertaken following the PRISMA-Scr guidelines. Nine databases were searched and a review team of five people followed a process using defined inclusion and exclusion criteria. Data were then analysed to answer the specific questions of the review. The World Health Organization's International Classification of Functioning Disability and Health was used to map outcomes across the domains. A total of 90 studies were included. The most reported frailty measure was the frailty phenotype. The most reported outcomes were mortality, hospitalisation and healthcare utilisation. Health-related quality of life was the most common patient-reported outcome measure. There were few intervention studies and limited evidence of patient and carer perspectives. This scoping review highlights important areas for further research in older people living with frailty and ACKD. This includes a 'gold standard' measure for identifying frailty, interventions and improvements in outcome measures that matter to patients (including studies that focus on carers and carer burden) and priority setting for future research.

Effect of a home-based resistance exercise program in elderly participants with osteoporosis: a randomized controlled trial

The effectiveness of home-based resistance exercise in elder participants with osteoporosis remains unclear. This study demonstrates the beneficial effects of this mode of exercise on improving physical function, increasing confidence in exercise, and reducing fear of falling.

INTRODUCTION

This study aims to evaluate the effect of a home-based resistance exercise (HBRE) program versus control on physical function, exercise self-efficacy, falling efficacy, and health-related quality of life (HRQOL).

METHODS

This randomized controlled trial included 72 elderly participants with osteoporosis. Participants in the intervention group received a 12-week HBRE program, and the control group received usual care. The primary outcome was physical function, including muscle strength and balance ability; secondary outcomes were exercise self-efficacy, falling efficacy, and HRQOL. Within-group and between-group changes in outcome were evaluated by t-test and rank-sum test.

RESULTS

A total of 68 subjects were included in the final analysis. Improvement in physical function was significantly greater in the HBRE group compared with controls. On a psychological level, exercise self-efficacy and falling efficacy improved significantly in the HBRE group; no significant change was observed in the control group. Most of the dimensions of HRQOL demonstrated improvements as well. The adherence was 85.29%, with no adverse events related to the exercise.

CONCLUSION

A 12-week HBRE program was safe non-pharmacological therapy for elderly participants with osteoporosis, improving physical function, exercise self-efficacy, reduced fear of falling, and improved HRQOL.

TRIAL REGISTRATION

Chinese Clinical Trial Register: ChiCTR2100051455. Registered 23.09.21. Retrospectively registered.

Association Between Exercise Self-Efficacy and Health-Related Quality of Life Among Dialysis Patients: A Cross-Sectional Study

Background

Exercise self-efficacy is a vital determinant of an individual’s active participation in regular exercise, and exercise is a critical component of improving health-related quality of life (HRQOL) in dialysis patients. This study aimed to describe the relationship between exercise self-efficacy and HRQOL in dialysis patients.

Materials and Methods

A cross-sectional study was conducted in Shanghai, China. Structured questionnaires distributed to the patients collected socio-demographic and disease-related information. Physical activity was assessed by a self-administered questionnaire, and the exercise self-efficacy scale (ESES) was used to measure exercise self-efficacy. HRQOL was evaluated by the kidney disease quality of life instrument-short form version 1.3 (KDQOL-SF™ v1.3). Data were analyzed using a univariate generalized linear model, Spearman correlation, and hierarchical multiple regression.

Results

A positive association was observed between exercise self-efficacy and HRQOL (r = 0.310, p < 0.001). Physical activity as a predictor variable explained 9.8% of the variance in overall HRQOL (p < 0.001). Exercise self-efficacy explained an additional 7.1% of the HRQOL variance. In total, 24.6% of the variation in the HRQOL was explained by the socio-demographic variables, disease-related factors, physical activity, and exercise self-efficacy.

Conclusion

Overall, only 16.9% of the change in HRQOL was explained by physical activity and exercise self-efficacy. Future research is still needed to further explore the factors influencing the HRQOL in dialysis patients. However, this finding suggests the need to consider the importance of HRQOL and physical activity as well as exercise self-efficacy when developing intervention programs.