Physical Activity in Patients Treated With Peritoneal Dialysis: A Systematic Review and Meta-analysis

Dyslipidemia in Peritoneal Dialysis: Implications for Peritoneal Membrane Function and Patient Outcomes

Dyslipidemia is a common metabolic complication in patients undergoing peritoneal dialysis (PD) and has traditionally been viewed primarily in terms of cardiovascular risk. Current guidelines do not recommend initiating lipid-lowering therapy in dialysis patients due to insufficient evidence of its benefits on cardiovascular mortality. However, the impact of dyslipidemia in PD patients may extend beyond cardiovascular concerns, influencing PD-related outcomes such as the peritoneal ultrafiltration rate, residual kidney function, PD technique survival, and overall mortality. This review challenges the traditional perspective by discussing dyslipidemia's potential role in PD-related complications, which may account for the observed link between dyslipidemia and increased all-cause mortality in PD patients. It explores the pathophysiology of dyslipidemia in PD, the molecular mechanisms linking dyslipidemia to peritoneal membrane dysfunction, and summarizes clinical evidence supporting this hypothesis. In addition, this paper examines the potential for therapeutic strategies to manage dyslipidemia to improve peritoneal membrane function and patient outcomes. The review calls for future research to investigate dyslipidemia as a potential contributor to peritoneal membrane dysfunction and to develop targeted interventions for PD patients.

The role of exercise training on cardiovascular risk factors and heart disease in patients with chronic kidney disease G3-G5 and G5D: a Clinical Consensus Statement of the European Association of Preventive Cardiology of the ESC and the European Association of Rehabilitation in Chronic Kidney Disease

Cardiovascular (CV) morbidity and mortality is high in patients with chronic kidney disease (CKD). Most patients reveal a high prevalence of CV risk factors such as diabetes or arterial hypertension and many have manifest cardiovascular disease (CVD), such as coronary artery disease and chronic heart failure with an increased risk of clinical events including sudden cardiac death. Diabetes mellitus and hypertension contribute to the development of CKD and the prevalence of CKD is in the range of 20-65% in diabetic and 30-50% in hypertensive patients. Therefore, prevention and optimal treatment of CV risk factors and comorbidities are key strategies to reduce CV risk and improve survival in CKD. Beyond common CV risk factors, patients with CKD are often physically inactive and have low physical function leading to subsequent frailty with muscle fatigue and weakness, sarcopenia and increased risk of falling. Consequently, the economic health burden of CKD is high, requiring feasible strategies to counteract this vicious cycle. Regular physical activity and exercise training (ET) have been shown to be effective in improving risk factors, reducing CVD and reducing frailty and falls. Nonetheless, combining ET and a healthy lifestyle with pharmacological treatment is not frequently applied in clinical practice. For that reason, this Clinical Consensus Statement reviews the current literature and provides evidence-based data regarding the role of ET in reducing CV and overall burden in patients with CKD. The aim is to increase awareness among cardiologists, nephrologists, and healthcare professionals of the potential of exercise therapy in order to encourage implementation of ET in clinical practice, eventually reducing CV risk and disease, as well as reducing frailty in patients with CKD G3-G5D.

Exercise perceptions and practices of people receiving peritoneal dialysis: An international cross-sectional survey

BACKGROUND

Low physical activity and functional impairment are prevalent and unaddressed in people receiving peritoneal dialysis (PD). Exercise has been shown to improve physical function and mental health for people with kidney disease.

METHODS

Cross-sectional descriptive survey aimed at identifying the exercise and physical activity perceptions and practice patterns of people receiving PD. The survey was developed and pretested with persons living with kidney disease, PD clinicians and exercise specialists.

RESULTS

There were 108 respondents (people receiving PD) with the majority from Canada (68%) and the United Kingdom (25%). Seventy-one per cent were engaged in physical activity two or more times per week. Most (91.8%) believed that physical activity is beneficial, and 61.7% reported healthcare provider discussion about physical activity. Perceptions regarding weightlifting restrictions varied: 76% were told not to lift weight with a maximum amount ranging from 2 kg to 45 kg. Few (28%) were instructed to drain PD fluid prior to physical activity. Mixed advice regarding swimming ability was common (44% were told they could swim and 44% were told they should not).

CONCLUSIONS

Knowledge gaps suggest that education for both healthcare providers and patients is needed regarding the practice of exercise for people living with PD. Common areas of confusion include the maximum weight a person should lift, whether exercise was safe with or without intrabdominal PD fluid in situ and whether swimming is allowed. Further research is needed to provide patients with evidence-based recommendations rather than defaulting to restricting activity.

Home-based exercise in dialysis patients with end-stage renal disease: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Lack of exercise may reduce the quality of life, physical capability, and functional capability of dialysis patients. Home-based exercise seems to be a desirable form of low-cost intervention. But the effectiveness of this intervention in the dialysis population is still unclear. The purpose of this meta-analysis is to provide effective evidence to determine the impact of home-based exercise on functional capacity, physical capacity, muscular strength, biochemical parameters, and health-related quality of life among dialysis patients with end-stage renal disease (ESRD).

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were searched from inception to May 2023, to identify potential randomized controlled trials (RCTs) assessing the effectiveness of home-based exercise in dialysis patients with ESRD. Two independent reviewers selected studies, extracted data, and assessed the risk of bias using the Cochrane tool. Evidence summary using fixed or random effects for meta-analysis.

RESULTS

Twelve RCTs including 1008 dialysis patients met the inclusion criteria. The meta-analysis showed significant effects of home-based exercise on physical capacity. Seven studies reported the results of the 6-min walking test, compared with short-term (0-3 months) home-based exercise (P = 0.76), long-term (3-6 months) interventions (P < 0.001) can significantly improve the results of the 6-min walking test. The results showed that home-based exercise did significantly improve patients' VO2 peak (P = 0.007). Compared with center-based exercise or usual care, home exercise did not significantly improve handgrip strength, quality of life or CRP and other biochemical parameters (P > 0.05).

CONCLUSION

The results showed that long-term home-based exercise can improve walking ability. In addition, home-based exercise had the benefit on the VO2 peak of ESRD patients receiving dialysis patients. However, there was no statistically significant difference in handgrip strength, health-related quality of life, CRP, and other biochemical parameters.

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.

Reasons for kidney transplant refusal among patients receiving peritoneal dialysis: A qualitative study

BACKGROUND

Even though kidney transplantation has better outcomes compared to dialysis therapies, some patients undergoing peritoneal dialysis (PD) refuse to consider kidney transplantation. Identification of the underlying reason for patient refusal may improve patients' acceptance of kidney transplantation.

AIM

The aim of this study was to describe the reasons given by Iranian PD patients for refusing kidney transplantation.

METHOD

Eighteen patients undergoing PD participated. Data were collected using semi-structured interviews and were analysed using conventional qualitative content analysis.

RESULTS

The analysis leads to the emergence of two categories and six subcategories: negative outcomes of kidney transplantation (financial burden, psychosocial problems and physical complications) and doubtful factors for kidney transplantation (negative attitudes towards kidney transplantation, long waiting time for kidney transplantation and compatibility of PD with daily life). The financial burden and long waiting time for kidney transplantation were the most important factors in the reluctance of kidney transplantation by PD patients.

IMPLICATION FOR PRACTICE

Patients undergoing PD declined kidney transplantation for several reasons, such as financial burden, fear of post-transplantation side effects, long waiting time for kidney transplantation. Reducing the time of kidney transplantation and insurance coverage of transplant costs can change the attitude of PD patients towards transplant.

Prevalence and influencing factors of fatigue among patients undergoing continuous ambulatory peritoneal dialysis: A cross-sectional study

Background

Fatigue is one of the most commonly reported symptoms among patients undergoing continuous ambulatory peritoneal dialysis (CAPD). However, only a few studies have addressed the prevalence of fatigue and its influencing factors within this population in Thailand.

Objective

This study aimed to explore the prevalence of fatigue and its influencing factors, including duration of CAPD initiation, body mass index, insomnia, social support, functional status, and depression among patients undergoing CAPD.

Methods

This cross-sectional study involved 136 participants from the outpatient department of a general hospital in Thailand. Data were collected from January to March 2023, utilizing validated self-reported questionnaires, which included the Center for Epidemiologic Study Depression Scale, Insomnia Severity Index, Multidimensional Scale of Perceived Social Support, Functional Status Scale, and Fatigue Severity Scale. Data were analyzed using descriptive statistics, Pearson's product-moment correlation, and Stepwise multiple regressions.

Results

The study achieved a 100% participation rate among the selected participants. The prevalence of fatigue among patients undergoing CAPD was 55.88%, including mild fatigue (20.59%), moderate fatigue (19.85%), and severe fatigue (15.44%). Bivariate analysis indicated that fatigue-related factors were insomnia, depression, body mass index, social support, and functional status. However, the multiple regression analysis revealed that only insomnia (β = 0.399, p <0.001), social support (β = -0.302, p <0.001), depression (β = 0.201, p = 0.003), and functional status (β = -0.149, p = 0.021) jointly influenced fatigue among patients undergoing CAPD, explaining 50.10 percent of the variance (R2 = 0.501, F(4, 131) = 32.871, p <0.001).

Conclusion

The findings indicated that more than half of the participants experienced fatigue. Insomnia, social support, depression, and functional status emerged as significant predictive factors of fatigue. Therefore, it is advisable for nurses and other healthcare providers to evaluate fatigue and its associated factors routinely. Nursing interventions to alleviate fatigue should prioritize improvements in sleep quality, reduction of depression, preservation of functional status, and promotion of family engagement.

An International Survey of Peritoneal Dialysis Exercise Practices and Perceptions

Introduction

Low activity levels and poor physical function are associated with technique failure and mortality in people receiving peritoneal dialysis (PD). Adequate levels of physical function are required to maintain independence for people choosing this predominantly home-based therapy. The objective of this study was to identify the exercise-related perceptions and practices of PD clinicians globally.

Methods

We conducted a cross-sectional survey of PD clinicians from English-, Thai-, Spanish-, and Portuguese-speaking PD-prevalent countries exploring clinicians' perceptions and practices of swimming, activity following PD catheter insertion, lifting, and falls prevention. This study was convened by the International Society of Peritoneal Dialysis and Global Renal Exercise Network between July and December 2021.

Results

Of 100 of the highest PD-prevalent countries, 85 responded and were represented in the findings. A total of 1125 PD clinicians (448 nephrologists, 558 nephrology nurses, 59 dietitians, and 56 others) responded from 61% high-income, 32% upper middle-income and 7% lower middle-income countries. The majority (n = 1054, 94%) agreed that structured exercise programs would be beneficial for people receiving PD. Most respondents believed people on PD could perform more exercise (n = 907, 81%) and that abdominal strengthening exercises could be safely performed (n = 661, 59%). Compared to clinicians in high-income countries, clinicians from lower middle-income status (odds ratio [OR], 5.57; 1.64 to 18.9) are more likely to promote participation in physical activity.

Conclusion

Clinicians know the importance of physical activity in people receiving PD. Exercise counseling and structured exercise plans could be included in the standard care of people receiving PD to maintain independence.

Physical exercise and peritoneal dialysis: An area yet to be explored

Health-related quality of life (HRQoL) of patients suffering from chronic kidney disease (CKD) is profoundly impaired by their frailty, disability and decreased physical capacity. Especially among older patients, a high prevalence of low physical activity levels and reduced functional performance has been reported. Physical exercise training has been shown to have a beneficial impact, counteracting these same hazardous consequences of inactivity and sedentarism both on CKD and end-stage kidney disease (ESKD) patients on hemodialysis (HD) treatment. The evidence-based knowledge on the effects of physical exercise on ESKD patients undergoing Peritoneal Dialysis (PD) treatment is scarce, even though this is a continually growing population that shares the same risk factors and desired clinical outcomes as the previously mentioned groups of patients. Further investigation will be necessary to clarify whether this exercise-based approach may be suitable for the PD population. This paper's purpose is to review the available literature, including randomized controlled trials, reviews and meta-analysis results that assessed the impact of physical exercise on patients under PD treatment bearing in mind their HRQoL, physical functioning and cardiovascular parameters. Furthermore, it aims to evaluate the perceived significant barriers and limitations of the PD population in what concerns physical exercise practice and how nephrologists should address them.

Physical activity and exercise in peritoneal dialysis: International Society for Peritoneal Dialysis and the Global Renal Exercise Network practice recommendations

Life participation requiring physical activity and physical function is a key patient-reported outcome for people receiving peritoneal dialysis (PD). Clinician guidance is required from multidisciplinary sources regarding exercise and activity advice to address the specific needs of this group. From August 2020 through to June 2021, the Global Renal Exercise Network and the International Society for Peritoneal Dialysis reviewed the published literature and international clinical experience to develop a set of clinical practice points. A set of questions relevant to physical activity and exercise were developed from the perspective of a person receiving PD and were the basis for the practice point development. The GRADE framework was used to evaluate the quality of evidence and to guide clinical practice points. The review of the literature found sparse quality evidence, and thus the clinical practice points are generally based on the expert consensus of people receiving PD, PD exercise expert clinicians and experienced PD exercise researchers. Clinical practice points address timing of exercise and activity (post-catheter insertion, peritoneal space empty or full), the uptake of specific activities (work, sex, swimming, core exercise), potential adverse outcomes related to activity and exercise (exit site care, perspiration, cardiovascular compromise, fatigue, intra-abdominal pressure), the effect of exercise and activity on conditions of interest (mental health, obesity, frailty, low fitness) and exercise nutrition.

Comparisons of physical activity and understanding of the importance of exercise according to dialysis modality in maintenance dialysis patients

Data regarding the status of physical activity or understanding of the importance of exercise, such as barriers of exercise or enablers of exercise, in dialysis patients were insufficient. This study aimed to evaluate the status of physical activity and the understanding of the importance of exercise in Korean dialysis patients. The study participants were recruited from 27 hospitals or dialysis centers (n = 1611). Physical activity was evaluated using the Korean version of the International Physical Activity Questionnaire-Short Form. High physical activity was defined as ≥ 600 metabolic equivalent of task (MET). Knowledge about the importance of exercise, enabler for regular exercise, benefits of exercise, and barrier to exercise was evaluated. Health-related quality of life (HRQoL) was assessed by the Kidney Disease Quality of Life version 1.3. The number of participants in the hemodialysis (HD) and peritoneal dialysis (PD) groups was 1247 and 364, respectively. The intensity of physical activity did not differ between the two modalities. The time of physical activity was longer in HD patients than in PD patients, which resulted in greater MET values and the number of high physical activity. There were 762 (61.1%) HD patients and 281 (77.2%) PD patients who heard of the importance of exercise (P < 0.001). In both HD and PD patients, dialysis staff played the most significant role as educators on the importance of exercise and enablers of exercise. The most important barriers to exercise were poor motivation and fatigue in both modalities. HD patients exhibited greater differences in HRQoL scales across two physical activity levels, compared to PD patients. Our study showed that the barrier to exercise and the enablers of exercise were poor motivation/fatigue and encouragement from dialysis staff, respectively.

Physical exercise and peritoneal dialysis: An area yet to be explored

Health-related quality of life (HRQoL) of patients suffering from chronic kidney disease (CKD) is profoundly impaired by their frailty, disability and decreased physical capacity. Especially among older patients, a high prevalence of low physical activity levels and reduced functional performance has been reported. Physical exercise training has been shown to have a beneficial impact, counteracting these same hazardous consequences of inactivity and sedentarism both on CKD and end-stage kidney disease (ESKD) patients on hemodialysis (HD) treatment. The evidence-based knowledge on the effects of physical exercise on ESKD patients undergoing Peritoneal Dialysis (PD) treatment is scarce, even though this is a continually growing population that shares the same risk factors and desired clinical outcomes as the previously mentioned groups of patients. Further investigation will be necessary to clarify whether this exercise-based approach may be suitable for the PD population. This paper's purpose is to review the available literature, including randomized controlled trials, reviews and meta-analysis results that assessed the impact of physical exercise on patients under PD treatment bearing in mind their HRQoL, physical functioning and cardiovascular parameters. Furthermore, it aims to evaluate the perceived significant barriers and limitations of the PD population in what concerns physical exercise practice and how nephrologists should address them.

Prevalence and correlates of physical activity across kidney disease stages: an observational multicentre study

BACKGROUND

People with chronic kidney disease (CKD) report high levels of physical inactivity, a major modifiable risk factor for morbidity and mortality. Understanding the biological, psychosocial and demographic causes of physical activity behaviour is essential for the development and improvement of potential health interventions and promotional initiatives. This study investigated the prevalence of physical inactivity and determined individual correlates of this behaviour in a large sample of patients across the spectrum of kidney disease.

METHODS

A total of 5656 people across all stages of CKD (1-2, 3, 4-5, haemodialysis, peritoneal dialysis and renal transplant recipients) were recruited from 17 sites in England from July 2012 to October 2018. Physical activity was evaluated using the General Practice Physical Activity Questionnaire. Self-reported cardiorespiratory fitness, self-efficacy and stage of change were also assessed. Binominal generalized linear mutually adjusted models were conducted to explore the associations between physical activity and correlate variables. This cross-sectional observational multi-centre study was registered retrospectively as ISRCTN87066351 (October 2015).

RESULTS

The prevalence of physical activity (6-34%) was low and worsened with disease progression. Being older, female and having a greater number of comorbidities were associated with greater odds of being physically inactive. Higher haemoglobin, cardiorespiratory fitness and self-efficacy levels were associated with increased odds of being active. Neither ethnicity nor smoking history had any effect on physical activity.

CONCLUSIONS

Levels of physical inactivity are high across all stages of CKD. The identification of stage-specific correlates of physical activity may help to prioritize factors in target groups of kidney patients and improve the development and improvement of public health interventions.

Perceptions of exercise benefits and barriers: the influence on physical activity behaviour in individuals undergoing haemodialysis and peritoneal dialysis

Background

Despite growing evidence about the benefits of physical activity and exercise in patients receiving dialysis, physical inactivity is highly prevalent. This may be due to uncertainty and lack of appropriate guidance about exercise, or driven by the relative barriers and benefits that patients perceive. Understanding these perceptions in dialysis patients may inform interventions aimed to increase exercise participation.

Methods

Perceived benefits and barriers to exercise were measured by the ‘Dialysis Patient-perceived Exercise Benefits and Barriers Scale’ (DPEBBS). Self-reported physical activity status was assessed by the ‘General Practice Physical Activity Questionnaire’. Barriers and benefits to exercise were classed as binary variables (i.e. yes and no). Frequency analyses and chi-squared tests were conducted to compare the differences perceived by people on haemodialysis (HD) and peritoneal dialysis (PD). Binominal logistical regression was performed to determine which perceived barriers and benefits had the biggest impact on physical activity status.

Results

One thousand twenty-two HD and 124 PD patients completed the DPEBBS. A greater proportion of HD than PD patients reported ‘reduces body pain’ (P = 0.013), ‘delays decline in body function’ (P = 0.01), and ‘improves quality of life’ (P = 0.033) as benefits of exercise. No differences in barriers were observed. Tiredness was the most reported barrier to exercise. Patients who perceived ‘other comorbidities’ (OR 3.389, P < 0.001) or ‘burden of family’ (OR 3.168, P < 0.001) as barriers were 3 times more likely to be inactive.

Conclusions

Dialysis patients perceive several barriers which may prevent them from engaging in physical activity. Addressing these barriers may be key to increasing participation in physical activity and exercise.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40620-021-01024-y.

Home-based exercise and bone mineral density in peritoneal dialysis patients: a randomized pilot study

BACKGROUND

The prevalence of osteopenia and osteoporosis is higher in patients with chronic kidney disease than that in the general population. Although physical exercise prevents bone loss in hemodialysis (HD) patients, previous studies have not focused on peritoneal dialysis (PD) patients. Therefore, we aimed to evaluate the effects of home-based exercise on bone mineral density (BMD) in patients with PD.

METHODS

Stable outpatients undergoing PD were randomly assigned to the intervention group (n = 26; male, 20; median age, 66 years) or usual-care group (n = 27; male, 21; median age, 64 years). Patients in the intervention group performed home-based exercises (resistance exercise, stretching, and aerobic exercise such as walking) for 6 months, whereas those in the usual-care group performed stretching and their usual physical activity. Based on dual X-ray absorptiometry, the primary outcomes were the BMD data of the lumbar spine and proximal femoral neck. Secondary outcomes included physical function and physical activity. Pre- and post-intervention values were compared.

RESULTS

There was no significant within-group change in the BMD of the lumbar spine, femoral neck, and hip after 6 months of the exercise program. The intervention group had significantly improved 30-s chair-stand test, 6-min walk test, and physical activity results.

CONCLUSIONS

Home-based exercises in patients with PD did not improve BMD at any of the sites evaluated. Improvement in physical function and physical activity may reduce the risk of falls in patients with PD.

TRIAL REGISTRATION

UMIN Clinical Trials Registry, UMIN000041678 . Registered September 4, 2020; retrospectively registered.

High Levels of Physical Activity May Promote a Reduction in Bone Mineral Density in Peritoneal Dialysis

Background and objectives: Peritoneal dialysis (PD) patients are expected to present lower levels of physical activity, unhealthy changes at the body composition level, and low levels of strength. Firstly, this study aimed to report the sex differences in physical activity, body composition and muscle strength and the relations among these variables. Secondly, we analyze the relationship between physical activity and biochemical parameters. Materials and Methods: Thirty-four patients (13 women and 21 men) participated in this study. Body composition was assessed by bioimpedance and dual-energy X-ray absorptiometry (DXA), and maximum isokinetic unilateral strength, analytical parameters and physical activity levels were evaluated. Results: The men showed higher values for weight, height, lean body mass, bone mineral content, bone mineral density (BMD) and total body water, while women showed higher values for the percentage of fat mass and hydration of lean body mass (p < 0.05). No differences between the sexes were found in different levels of physical activity; however, males registered significantly higher values for isokinetic strength variables except for knee extensor strength. BMD was positively related to sedentary activity and negatively related to moderate and vigorous activity (r = 0.383 and r = -0.404, respectively). Light physical activity was negatively correlated with albumin (r = -0.393) and total protein (r = -0.410) levels, while moderate/vigorous activity was positively correlated with urea distribution volume (r = 0.446) and creatinine clearance (r = 0.359) and negatively correlated with the triglyceride level (r = -0.455). Conclusions: PD patients with higher levels of physical activity present better results in terms of body composition and biochemical parameters. Additional studies should be conducted to clarify the relation between physical activity level and BMD.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

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.

Prescribing peritoneal dialysis and achieving good quality dialysis in low and low-middle income countries

The provision of long-term renal replacement therapies for patients with end-stage kidney disease (ESKD) in low and low-middle income countries (LLMICs) has been a pervasive challenge, impeded mainly by monetary constraints, limited health-care resources, and geographical and logistic difficulties. Even for patients who could initiate dialysis, discontinuation of dialysis treatment due to the lack of financial sustainability is a valid concern. While the delivery of high-quality dialysis should not be compromised in these settings, perpetuity on dialysis is of paramount consideration for these patients, with sustaining life being just as important as achieving clinical well-being. As intensification of peritoneal dialysis (PD) prescription comes with immense cost in these settings, the strategy for stretching affordability of dialysis involves optimizing the number of PD exchanges required or delaying the transition to a high PD dose of four bags per day of continuous ambulatory PD (CAPD) prescription. This can be accomplished through the use of low-cost adjunctive treatment, by preserving residual kidney function and adopting incremental PD. The use of expensive, complex, or inaccessible monitoring tools for peritoneal membrane function and dialysis clearance could be replaced by clinical assessment and widely available biochemical indicators, which will significantly reduce the investigation costs, with consequent savings that could allow for lengthening the duration of PD therapy. Finally, it is important for each PD program in LLMICs to monitor these outcome indicators, to ensure the consistent delivery of acceptable quality of PD to their patients.

The Exercise Perceptions of People Treated with Peritoneal Dialysis

BACKGROUND

Individuals receiving peritoneal dialysis (PD) report low levels of physical activity, which increases their risk of morbidity and mortality. Little is known about their perceptions towards barriers and benefits of exercise or physical activity.

AIM

The aim of this study was to explore the perceptions of exercise among people receiving PD.

STUDY DESIGN

Cross-sectional survey.

PARTICIPANTS

Thirty-nine adults (12 female and 27 male) with a mean age of 65 years and a median of 8 months receiving PD from one Australian dialysis service.

MEASUREMENTS

The 26-item Dialysis Patient-Perceived Exercise Benefits and Barriers Survey was adapted to PD in order to measure self-reported barriers and benefits of exercise for people being treated with PD.

RESULTS

The majority of the respondents reported positive perceptions towards exercise with 84.6% of the participants agreeing that exercise prevents muscular wasting; 71.8% agreed that exercise can postpone a decline in body function; and 69.2% agreed that exercise improves general well-being. In terms of barriers, symptoms including tiredness (69.2%) and body pain (43.6%), worrying about a fall (33.3%) and lack of exercise-related information (25.6%) were the main perceived barriers to exercise. Only 10% agreed that exercise may affect their PD catheter with 23% agreeing that fluid in their peritoneum was a barrier to exercise.

CONCLUSION

People on PD hold positive perceptions towards exercise but face a number of perceived barriers to physical activity. Clinicians can acknowledge these barriers and focus on helping people on PD to overcome their perceived barriers to encourage sustained exercise participation.

In Search of a Simple and Reliable Method of Measuring Intra-abdominal Pressure in Peritoneal Dialysis Patients

Background:

Patients treated with peritoneal dialysis (PD) are at increased risk of developing mechanical complications such as dialysate leaks and hernias thought to be partially related to an increase in intra-abdominal pressure (IAP) secondary to dialysate in the abdomen. However, measurement of IAP requires specialized equipment that is not readily available in the home dialysis unit.

Objectives:

To develop a reliable method of measuring IAP in PD patients that could be easily used in the home dialysis unit. We hypothesized that the handheld Stryker pressure monitor would be suitable for this purpose via connection to the PD catheter.

Design:

Cross-sectional.

Setting:

Tertiary Care Hospital, Ottawa, Ontario, Canada.

Patients:

Patients who were having a PD catheter inserted via laparoscopic surgery at The Ottawa Hospital were recruited for the study.

Measurements:

With the patients at end-expiration, the IAP measured with the Stryker monitor connected to the PD catheter was compared with the insufflator pressures of 15, 10, and 5 mm Hg.

Methods:

Bland-Altman plots were constructed and intraclass correlation coefficients were calculated for each pressure.

Results:

Twelve patients participated in the study: 9 men and 3 women. They were on average 53 ± 15 years old and 81 ± 13.4 kg. Two patients had to be excluded from the analysis due to difficulties zeroing the Stryker pressure monitor at the time of surgery. There were also rapid fluctuations in the insufflator pressure recording, creating additional challenges in comparing the 2 measurements at end-expiration. The 95% limits of agreement for the Bland-Altman plots ranged from 7.9 (@15 mm Hg) to 12.2 (@10 mm Hg). The intraclass correlation coefficients for reliability of the individual measurements ranged from 0.015 (10 mm Hg) to 0.634 (15 mm Hg).

Limitations:

Small sample size and lack of a gold standard comparator may have affected our results.

Conclusions:

In our study, we used the operating room insufflator as the gold standard for measuring IAP. By Bland-Altman plots and intraclass correlation coefficients, the pressure values obtained with the Stryker pressure monitor were not a reliable estimate of insufflator IAP especially at lower pressures. Further studies are needed to identify an ideal tool for measurement of IAP to guide PD management.

Exercise and physical activity for people receiving peritoneal dialysis: Why not?

People with end-stage kidney disease (ESKD) receiving peritoneal dialysis (PD) are physically inactive leading to low physical function and poor health outcomes. Guidelines recommend that nephrologists encourage PD patients to increase their activity levels; however, PD patients are often discouraged from participating in exercise programs because of perceived barriers and a lack of precision about the appropriate exercise regimen. This review suggests ways forward to assist nephrology professionals to encourage PD patients to exercise, instead of creating barriers. The paper draws on the literature in addition to the experience of programs in France, the United States, and Australia to demonstrate the possibilities when considering increasing physical activity in this group.