Association of physical activity with mortality in the US dialysis population

Physical activity and exercise in chronic kidney disease: consensus statements from the Physical Exercise Working Group of the Italian Society of Nephrology

The Italian Society of Nephrology has tasked its Working Group on Physical Exercise with developing a consensus statement document on physical activity and exercise in patients with chronic kidney disease (CKD). This paper consists of 16 points that were discussed, and approved using the mini-Delphi method by 15 members of the working group. Each statement is based on a comprehensive review of the literature, clinical experience, and expert opinions. Overall, the statements affirm that regular physical activity and exercise training offer numerous benefits to CKD patients, including improved physical function, enhanced cardiometabolic and neuromuscular function, cognitive benefits, and an overall improvement in quality of life. Furthermore, exercise may provide nephroprotection and reduce mortality. These advantages are observed across all CKD stages, whether on conservative therapy or kidney replacement therapy (hemodialysis or peritoneal dialysis), and in kidney transplant recipients. Moreover, when physical activity and exercise training are implemented with appropriate precautions, they are safe in CKD patients. Gradual physical activity and customized exercise programs should be tailored to the patient's exercise tolerance, potentially enhancing compliance. Clinicians are encouraged to use a series of questionnaires and tests to assess the patient's level of physical activity and performance. However, exercise and physical activity are poorly implemented in clinical practice due to many barriers related to patients and healthcare staff. Overcoming these barriers requires the proactive role of the nephrologists, who should actively incorporate exercise training and promote physical activity within routine care plans. Adopting a multidisciplinary team approach, which includes nephrologists, nurses, exercise professionals, and dietitians, is crucial for providing comprehensive rehabilitation for CKD patients. Integrating new technologies and remote check ups could further enhance the effectiveness of these interventions.

Impact of physical activity on surrogate markers of cardiovascular disease in the haemodialysis population

Background

The haemodialysis (HD) population is sedentary, with substantial cardiovascular disease risk. In the general population, small increases in daily step count associate with significant reductions in cardiovascular mortality. This study explores the relationship between daily step count and surrogate markers of cardiovascular disease, including left ventricular ejection fraction (LVEF) and native T1 (a marker of diffuse myocardial fibrosis), within the HD population.

Methods

This was a post hoc analysis of the association between daily step count and metabolic equivalent of task (MET) and prognostically important cardiac magnetic resonance imaging parameters from the CYCLE-HD study (ISRCTN11299707). Unadjusted linear regression and multiple linear regression adjusted for age, body mass index, dialysis vintage, haemoglobin, hypertension and ultrafiltration volume were performed. Significant relationships were explored with natural cubic spline models with four degrees of freedom (five knots).

Results

A total of 107 participants were included [age 56.3 ± 14.1 years, 79 (73.8%) males]. The median daily step count was 2558 (interquartile range 1054-4352). There were significant associations between steps and LVEF (β = 0.292; P = .009) and steps and native T1 (β = -0.245; P = .035). Further modelling demonstrated most of the increase in LVEF occurred at up to 2000 steps/day and there was an inverse dose-response relationship between steps and native T1, with the most pronounced reduction in native T1 between ≈2500 and 6000 steps/day.

Conclusions

The results suggest an association between daily step count and parameters of cardiovascular health in the HD population. These findings support the recommendations for encouraging physical activity but are not the justification. Further research should evaluate whether a simple physical activity intervention improves cardiovascular outcomes in individuals receiving maintenance HD.

A Simple Exercise Program for Patients With End-Stage Kidney Disease to Improve Strength and Quality of Life: Clinical Research Protocol

Background

Most patients with end-stage kidney disease (ESKD) appreciate the importance of exercise and would like to increase their physical activity; however, they report a few key barriers, including (1) lack of physician advice to do so, (2) lack of safe and convenient programs (ie, appropriate for home or neighborhood), and (3) cost. Importantly, patients indicated in a previous survey that they would prefer an exercise program that improves muscle strength and symptoms, and are less interested in cardiovascular disease prevention.

Objective

To test the feasibility of a simple, prescribed exercise program using Nordic walking poles in patients with ESKD treated with dialysis.

Design

Randomized multicenter pilot trial of an exercise intervention that includes Nordic walking poles, personalized physician exercise prescriptions, pedometers, and access to exercise videos, compared with standard of care, in patients being treated with maintenance dialysis.

Setting

Multicenter tertiary care centers in Canada.

Patients

Ambulatory adult patients with ESKD treated with peritoneal dialysis or hemodialysis (HD) for at least 6 months at participating sites are potentially eligible. Inclusion criteria include ability to use Nordic walking poles (either de novo or in place of mobility aid) and to provide informed consent in English or in French. Exclusion criteria include (1) any absolute contraindication to exercise, (2) baseline step count >8000 steps/day, (3) planned living donor kidney transplant, and (4) participation in another interventional trial that may affect the results of this study.

Methods

This is a randomized multicenter pilot trial of an exercise intervention that consists of a prescription to exercise using Nordic walking poles, a pedometer to track activity, and access to exercise videos, with the comparator of standard of care (dialysis unit staff encouragement to exercise) in patients being treated with maintenance dialysis. Randomization is concealed and uses a 1:1 ratio for group assignment. Our specific aims are to determine the feasibility of patient recruitment, adherence to the exercise program (verified by step counts), and efficacy of the intervention on patient-important outcomes that were assessed as a priority by patients in a prior survey-specifically strength, fatigue, and sleep. We record days spent in hospital and loss of independent living to inform sample size calculations for a definitive trial of exercise in patient with ESKD treated with dialysis. Adverse events are closely monitored.

Outcomes

Primary: Our recruitment goal is 90 to 150 patients over 27 months; adherence success will be defined if >75% of randomized patients, excluding those who are transplanted or deceased, achieve >80% of their prescribed steps at 6 and 12 months. Secondary Efficacy Outcomes: (1) strength-hand grip strength and 5 times sit to stand, (2) energy-Short Form (SF)-36 vitality subscale, and (3) sleep-Pittsburg Sleep Quality Index will be assessed at baseline, 6, and 12 months.

Results

Trial recruitment started before the COVID-19 pandemic and the pandemic led to many interruptions and delays. Online exercise Web sites and a tailored video were added to the protocol to encourage activity when participants were unable or reluctant to walk in public places.

Limitations

This trial was designed to include ambulatory patients with ESKD and does not address the burden of disease in patients with very restricted mobility.

Trial Registration

NCT03787589.

Prevalence of Impaired Physical Mobility in Dialysis Patients: A Single-Centre Cross-Sectional Study

Impaired physical mobility in hemodialysis (HD) patients is considered an important modifiable risk factor of increased all-cause morbidity and mortality. To our knowledge, no study to date has determined the overall burden of limited physical mobility in prevalent HD patients. The aim of this research is to investigate impaired physical mobility and its clinical correlates. We conducted a cross-sectional observational study in all patients of the Centre for Acute and Complicated Dialysis at the University Medical Centre of Ljubljana, where the most complex patients receive HD on average three times per week. The data were collected through interviews based on a prepared questionnaire and medical history review. A total of 205 patients were included in this study (63.9 ± 15.4 years). Sixty percent (122/205) of the patients had little or no physical mobility impairment, and others were categorized with a minor or severe mobility limitation. A minor mobility impairment was found in 21% (43/205) of patients: 10 patients (5%) used a mobility aid in the form of a crutch, 9 patients (4%) were dependent on two crutches or a walker, and 24 patients (12%) were temporarily dependent on the assistance of a third person. Severe mobility limitations were observed in 22% (40/205) of patients, ranging from being confined to bed (19/205, 9%), confined to bed but able to perform some movements (19/205, 9%), and ambulatory but dependent on the assistance of a third person for locomotion (2/205, 1%). The most common causes of the limitation of mobility were neurological (19/40, 47.5%), cardiovascular (9/40, 22.5%), musculoskeletal (8/40, 20%), and other causes (4/40, 10%). A significant, moderate positive correlation was observed between mobility problems and the age of the participants (r = 0.36, p < 0.001), while a significant, small positive correlation was obtained between the mobility problems and C-reactive protein (r = 0.15, p = 0.044). Moreover, mobility problems had a small but significant negative correlation with albumin levels (r = -0.15, p = 0.042). When controlling for age, results yield no significant correlations, and, in regression analysis, only the age (p < 0.001) and male gender (p = 0.007) of the participants were independent predictors of mobility impairment. We conclude that impaired mobility has a high overall prevalence among chronic HD patients. Strategies to prevent and improve mobility limitations are strongly needed.

Exploring patients' experiences of the impact of dialysis therapies on quality of life and wellbeing

BACKGROUND

When people with chronic kidney disease reach kidney failure, renal replacement therapy is usually required to improve symptoms and maintain life. Although in-centre haemodialysis is most commonly used for this purpose, other forms of dialysis are available, including home haemodialysis and peritoneal dialysis.

OBJECTIVES

We aimed to explore the experiences of adults living with chronic kidney disease who were either approaching the need for dialysis or had reached kidney failure and were receiving a form of dialysis. In particular, we explored how different forms of dialysis affect their quality of life, wellbeing, and physical activity.

METHODS

Individual semistructured interviews were conducted with 40 adults with kidney failure, comprising four groups (n = 10 each): those receiving in-centre haemodialysis, home haemodialysis or peritoneal dialysis, or predialysis. Interviews were transcribed verbatim, thematically analysed, and then composite vignettes were subsequently developed to present a rich narrative of the collective experiences of each group.

FINDINGS

Compared with adults who were predialysis, quality of life and wellbeing improved upon initiation of their home haemodialysis or peritoneal dialysis. Conversely, minimal improvement was perceived by those receiving in-centre haemodialysis. Low physical activity was reported across all four groups, although those receiving home haemodialysis and peritoneal dialysis reported a greater desire and ability to be physically active than those in-centre.

CONCLUSION

These findings highlight that dialysis modalities not requiring regular hospital attendance (i.e., home haemodialysis and peritoneal dialysis) improve independence, quality of life, wellbeing, and can facilitate a more physically active lifestyle.

Study protocol of a randomized controlled trial of fistula vs. graft arteriovenous vascular access in older adults with end-stage kidney disease on hemodialysis: the AV access trial

BACKGROUND

Treatment of end-stage kidney disease (ESKD) with hemodialysis requires surgical creation of an arteriovenous (AV) vascular access-fistula (AVF) or graft (AVG)-to avoid (or limit) the use of a central venous catheter (CVC). AVFs have long been considered the first-line vascular access option, with AVGs as second best. Recent studies have suggested that, in older adults, AVGs may be a better strategy than AVFs. Lacking evidence from well-powered randomized clinical trials, integration of these results into clinical decision making is challenging. The main objective of the AV Access Study is to compare, between the two types of AV access, clinical outcomes that are important to patients, physicians, and policy makers.

METHODS

This is a prospective, multicenter, randomized controlled trial in adults ≥ 60 years old receiving chronic hemodialysis via a CVC. Eligible participants must have co-existing cardiovascular disease, peripheral arterial disease, and/or diabetes mellitus; and vascular anatomy suitable for placement of either type of AV access. Participants are randomized, in a 1:1 ratio, to a strategy of AVG or AVF creation. An estimated 262 participants will be recruited across 7 healthcare systems, with average follow-up of 2 years. Questionnaires will be administered at baseline and semi-annually. The primary outcome is the rate of CVC-free days per 100 patient-days. The primary safety outcome is the cumulative incidence of vascular access (CVC or AV access)-related severe infections-defined as access infections that lead to hospitalization or death. Secondary outcomes include access-related healthcare costs and patients' experiences with vascular access care between the two treatment groups.

DISCUSSION

In the absence of studies using robust and unbiased research methodology to address vascular access care for hemodialysis patients, clinical decisions are limited to inferences from observational studies. The goal of the AV Access Study is to generate evidence to optimize vascular access care, based on objective, age-specific criteria, while incorporating goals of care and patient preference for vascular access type in clinical decision-making.

TRIAL REGISTRATION

This study is being conducted in accordance with the tenets of the Helsinki Declaration, and has been approved by the central institutional review board (IRB) of Wake Forest University Health Sciences (approval number: 00069593) and local IRB of each participating clinical center; and was registered on Nov 27, 2020, at ClinicalTrials.gov (NCT04646226).

Exercise in the Prevention and Treatment of Type 2 Diabetes

Type 2 diabetes is a systemic, multifactorial disease that is a leading cause of morbidity and mortality globally. Despite a rise in the number of available medications and treatments available for management, exercise remains a first-line prevention and intervention strategy due to established safety, efficacy, and tolerability in the general population. Herein we review the predisposing risk factors for, prevention, pathophysiology, and treatment of type 2 diabetes. We emphasize key cellular and molecular adaptive processes that provide insight into our evolving understanding of how, when, and what types of exercise may improve glycemic control. © 2023 American Physiological Society. Compr Physiol 13:1-27, 2023.

Glittre activities of daily living test is reliable and valid in hemodialysis patients

PURPOSE

To examine the validity, and the relative and absolute within-day reliability of the TGlittre in chronic kidney disease patients undergoing hemodialysis (HD).

MATERIALS AND METHODS

Thirty HD patients (52 ± 12 years) undertook the TGlittre twice on a single day, in a cross-sectional design. For validation purposes, participants TGlittre performance and accelerometry-based physical activity were correlated. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable change (MDC) were determined to assess within-day reliability.

RESULTS

There was a moderate correlation between TGlittre performance and moderate to vigorous physical activity (r= -0.587; p= 0.001). The relative reliability of the test showed an ICC of 0.96. For the absolute reliability, the SEM was 13.05 s (0.22 min), and the MDC was 36.17 s (0.60 min).

CONCLUSIONS

TGlittre performance is associated with moderate to vigorous physical activity in HD patients, highlighting that those with higher levels of physical activity are likely to perform better on the TGlittre. Additionally, TGlittre shows a good to excellent intra-rater reliability and a low SEM. An MDC value was established.Implications for rehabilitationPatients on hemodialysis have a low physical capacity and often struggle to simply complete their physical activities of daily living.The TGlittre is a tool for assessing functional capacity through completion of multiple physical activities of daily living and can be easily applied in a clinical setting.TGlittre is a valid test that elicit reliable physiological, hemodynamic, and physical performance responses in HD patients.

Feasibility of randomized controlled trials and long-term implementation of interventions: Insights from a qualitative process evaluation of the PEDAL trial

Introduction

A multi-site randomized controlled trial was carried out between 2015 and 2019 to evaluate the impacts on quality of life of an intradialytic exercise programme for people living with chronic kidney disease. This included a qualitative process evaluation which gave valuable insights in relation to feasibility of the trial and of the intervention in the long-term. These can inform future clinical Trial design and evaluation studies.

Methods

A constructivist phenomenological approach underpinned face-to-face, semi-structured interviews. Purposive recruitment ensured inclusion of participants in different arms of the PEDAL Trial, providers with different roles and trial team members from seven Renal Units in five study regions. Following ethical review, those willing took part in one interview in the Renal Unit. Audio-recorded interviews were transcribed (intelligent verbatim) and inductively thematically analyzed.

Results

Participants (n = 65) (Intervention arm: 26% completed; 13% who did not; Usual care arm: 13%; 46% women; 54% men; mean age 60 year) and providers (n = 39) were interviewed (23% PEDAL Trial team members). Three themes emerged: (1) Implementing the Intervention; (2) Implementing the trial; and (3) Engagement of the clinical team. Explanatory theory named "the Ideal Scenario" was developed, illustrating complex interactions between different aspects of intervention and trial implementation with the clinical context. This describes characteristics likely to optimize trial feasibility and intervention sustainability in the long-term. Key aspects of this relate to careful integration of the trial within the clinical context to optimize promotion of the trial in the short-term and engagement and ownership in the long-term. Strong leadership in both the clinical and trial teams is crucial to ensure a proactive and empowering culture.

Conclusion

Novel explanatory theory is proposed with relevance for Implementation Science. The "Ideal Scenario" is provided to guide trialists in pre-emptive and ongoing risk analysis relating to trial feasibility and long-term intervention implementation. Alternative study designs should be explored to minimize the research-to-practice gap and optimize the likelihood of informative findings and long-term implementation. These might include Realist Randomized Controlled Trials and Hybrid Effectiveness-Implementation studies.

Frailty in end stage renal disease: Current perspectives

Frailty is common in end stage renal disease (ESRD) and is a marker of poor outcomes. Its prevalence increases as chronic kidney disease (CKD) progresses. There are different measurement tools available to assess frailty in ESRD. The pathogenesis of frailty in ESRD is multifactorial including uraemia and dialysis related factors. In this current review, we discuss the importance of frailty, its pathogenesis, screening methods, prognostic implications and management strategies in context of ESRD.

Long-Term Effect of Physical Exercise on the Risk for Hospitalization and Death in Dialysis Patients: A Post-Trial Long-Term Observational Study

BACKGROUND AND OBJECTIVES

In the EXerCise Introduction to Enhance Performance in Dialysis (EXCITE) trial, a simple, personalized 6-month walking exercise program at home during the day off of dialysis improved the functional status and the risk for hospitalization in patients with kidney failure. In this post-trial observational study, we tested whether the same intervention was associated with a lower long-term risk of death or hospitalization (combined end point) during a follow-up extended up to 36 months.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In total, 227 patients (exercise, n=104; control, n=123) completed the 6-month trial and entered the post-trial observational study. Data were analyzed by unadjusted and adjusted Cox regression analyses and Bayesian analysis.

RESULTS

In the long-term observation (up to 36 months), 134 events were recorded (eight deaths not preceded by hospitalization and 126 hospitalizations, which were followed by death in 38 cases). The long-term risk for hospitalization or death was 29% lower (hazard ratio, 0.71; 95% confidence interval, 0.50 to 1.00), and in an analysis stratified by adherence to the walking exercise program during the 6-month trial, the subgroup with high adherence (>60% of prescribed sessions) had a 45% lower risk as compared with the control group (hazard ratio, 0.55; 95% confidence interval, 0.35 to 0.87). A Bayesian analysis showed that the posterior probability of a hazard ratio of 0.71 (95% confidence interval, 0.50 to 1.00) for the risk of the composite outcome observed in the post-trial observational study was 93% under the conservative prior and 97% under the optimistic prior. Sensitivity analyses restricted to the risk of hospitalization only or censoring patients at the time of transplantation fully confirmed these findings.

CONCLUSIONS

A simple, personalized, home-based, low-intensity exercise program was associated with a lower risk of hospitalization.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

EXerCise Introduction to Enhance Performance in Dialysis (EXCITE), NCT01255969.

Performance Status Modifies the Association Between Vitamin D Receptor Activator and Mortality or Fracture: A Prospective Cohort Study on the Japanese Society for Dialysis Therapy (JSDT) Renal Data Registry

Immobilization osteoporosis is characterized by excess bone resorption. Vitamin D receptor activators (VDRA) might have adverse effects in immobilized patients. The objective of this study was to elucidate the impact of performance status (PS) on the associations between VDRA use and outcomes among hemodialysis patients. This is a prospective cohort study. Adults on hemodialysis in the Japanese Society for Dialysis Therapy (JSDT) Renal Data Registry were included. Exposure of interest was the use of VDRA. Outcomes were all-cause mortality and hip fracture. Associations between VDRA use and mortality or hip fractures were examined by Cox and Poisson regression analyses, respectively. Among 208,512 subjects, 128,535 were on VDRA. Poor PS was associated with higher calcium (Ca), lower parathyroid hormone, and higher alkaline phosphatase levels. The association between higher Ca levels and VDRA use was stronger among those with poor PS (p interaction 0.007). Adjusted hazard ratio (HR) (95% confidence interval [CI]) for mortality and incidence rate ratio (IRR) for hip fracture was 1.02 (95% CI, 0.99-1.05) and 0.93 (0.86-1.00) among users of VDRA, respectively. The VDRA use was associated with lower mortality and incidence of hip fractures among subjects with good PS but not among subjects with poor PS (p interaction 0.03 and 0.05). Effect modification by PS was observed for cardiovascular (CV) mortality but not for non-CV mortality. In conclusion, VDRA use was associated with better outcomes only among those with good PS. These results suggest that bone and mineral disorders among hemodialysis patients should be treated differently, depending on their performance status. © 2022 American Society for Bone and Mineral Research (ASBMR).

Renal rehabilitation as a management strategy for physical frailty in CKD

An aging population and the increasing prevalence of lifestyle-related diseases have led to a worldwide increase in the rate of chronic kidney disease requiring renal replacement therapy. The mean age of individuals requiring dialysis therapy has been increasing, and Japanese patients are aging more rapidly than those in the USA and Europe. Patients undergoing renal replacement therapy are at increased risk of sarcopenia/frailty compared with people with normal kidney function due to comorbid burden, long-standing malnutrition, chronic inflammation, metabolic acidosis, anabolic resistance, hormonal changes, physical inactivity and amino acid loss via dialysis treatment in addition to aging. Sarcopenia and frailty are serious global health problems that can decrease access to kidney transplantation and lead to various adverse health outcomes, including functional dependence, hospitalizations and deaths in patients on dialysis treatment. However, sarcopenia/frailty fortunately is potentially modifiable by early identification of poor physical functioning, sustainment and enhancement of daily physical activity, and participation in exercise treatments. The Japanese Society of Renal Rehabilitation was established in 2011 and published a clinical practice guideline for “Renal Rehabilitation” targeting nondialysis-dependent and dialysis-dependent patients and renal transplant recipients, in 2019. The guideline emphasized the importance of physical management for patients with kidney diseases in addition to nutritional supports and anemia management. Kidney health professionals should manage sarcopenia and physical frailty as a part of routine clinical care for patients undergoing hemodialysis to improve poor physical functioning, functional dependence, decreased quality of life and poor prognosis.

Intradialytic hypotension and objectively measured physical activity among patients on hemodialysis

BACKGROUND

Intradialytic hypotension is related to patient-reported outcomes such as post-dialysis fatigue, but its impact on physical activity has not been fully studied. We aimed to examine the relationship between intradialytic blood pressure (BP) and objectively measured physical activity.

METHODS

In this cross-sectional study, 192 hemodialysis patients underwent 4 weeks of physical activity measurement using triaxial accelerometers to measure step counts and moderate-to-vigorous physical activity (MVPA). Intradialytic BP parameters (pre-dialysis BP, post-dialysis BP, nadir BP, and fall in BP) were measured during all dialysis sessions. Mixed-effects linear regression models were used to analyze associations between intradialytic BP parameters and physical activity (1) after dialysis sessions on dialysis days and (2) on the following non-dialysis days.

RESULTS

The mean age of the patients was 71 years, and 47% had diabetes mellitus. Valid physical activity data were obtained in a total of 1938 dialysis days and 2629 non dialysis days. Lower nadir diastolic BP was significantly associated with lower step counts and shorter moderate-to-vigorous physical activity not only on dialysis days but also on the following non-dialysis days. Nadir diastolic BP showed a higher discrimination capacity for physical inactivity, defined as a step count < 4000 on non-dialysis days, than the other BP parameters. The optimal cutoff point of nadir diastolic BP for discriminating physical inactivity was 68 mmHg; its sensitivity and specificity were 66% and 67%, respectively.

CONCLUSIONS

Lower nadir diastolic BP was strongly associated with lower physical activity on both dialysis and non-dialysis days. Nadir diastolic BP may be a predictor for physical inactivity.

Does the interference phenomenon affect strength development during same-session combined rehabilitation program in hemodialysis patients?

INTRODUCTION

This study aimed to assess if an interference effect could blunt the neuromuscular gains induced by a same-session combined rehabilitation in hemodialysis (HD) patients.

METHODS

Patients exercised twice a week, for 16 weeks, over their HD sessions. They were either always trained with resistance and endurance exercises (continuous training, "CONT") or alternatively with 1 week of resistance alternated with 1 week of endurance (discontinuous training, "DISC"). Adherence and workload were continuously recorded. Short Physical Performance Battery (SPPB) score, one-leg balance test, and handgrip and quadriceps strength were evaluated before and after training intervention.

RESULTS

Adherence to both programs was high (>90%). SPPB score had significantly improved (CONT: +1.5 point, DISC: +1.2 pt, p < 0.001), like one-leg balance test (CONT: +3.7 s, DISC: +5.5 s, p < 0.05), handgrip strength of exercised (CONT: +5.5 kg, DISC: +5.6 kg, p < 0.001) and of nonexercised arm (CONT: +4.4 kg, DISC: +2.8 kg, p < 0.01) as well as maximal quadriceps strength (+22 N·m for dominant and +29 N·m for nondominant leg in both groups, p < 0.001) bearing no difference between the trainings.

CONCLUSION

Same-session combined training does not induce an interference effect in HD patients and temporal separation of exercises does not optimize strength gains. These practical data may be relevant for clinicians and practitioners to alternate endurance and resistance exercises.

Laxative use and mortality in patients on haemodialysis: a prospective cohort study

BACKGROUND

Patients on haemodialysis (HD) are often constipated. This study aimed to assess the relationship between constipation and mortality in such patients. In this study, constipation was defined as receiving prescription laxatives, based on the investigation results of "a need to take laxatives is the most common conception of constipation" reported by the World Gastroenterology Organization Global Guidelines.

METHODS

This cohort study included 12,217 adult patients on HD enrolled in the Japan-Dialysis Outcomes and Practice Patterns study phases 1 to 5 (1998 to 2015). The participants were grouped into two based on whether they were prescribed laxatives during enrolment at baseline. The primary endpoint was all-cause mortality in 3 years, and the secondary endpoint was cause-specific death. Missing values were imputed using multiple imputation methods. All estimations were calculated using a Cox proportional hazards model with an inverse probability of treatment weighting using the propensity score.

RESULTS

Laxatives were prescribed in 30.5% of the patients, and there were 1240 all-cause deaths. There was a significant association between laxative prescription and all-cause mortality [adjusted hazard ratio (AHR), 1.12; 95% confidence interval (CI): 1.03 to 1.21]. Because the Kaplan-Meier curves of the two groups crossed over, we examined 8345 patients observed for more than 1.5 years. Laxative prescription was significantly associated with all-cause mortality (AHR, 1.35; 95% CI: 1.17 to 1.55). The AHR of infectious death was 1.62 (95% CI: 1.14 to 2.29), and that of cancerous death was 1.60 (95% CI: 1.08 to 2.36). However, cardiovascular death did not show a significant inter-group difference.

CONCLUSIONS

Constipation requiring use of laxatives was associated with an increased risk of death in patients on HD. It is important to prevent patients receiving HD from developing constipation and to reduce the number of patients requiring laxatives.

Healthy Lifestyle and Mortality Among Adults Receiving Hemodialysis: The DIET-HD Study

RATIONALE & OBJECTIVE

A healthy lifestyle promotes cardiovascular health and reduces cardiac-related mortality in the general population but its benefits for people receiving maintenance hemodialysis are uncertain.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

5,483 of 9,757 consecutive adults receiving maintenance hemodialysis (January 2014 to June 2017, median dialysis vintage: 3.6 yrs) in a multinational private dialysis network and with complete lifestyle data.

EXPOSURES

Based on the American Heart Association's recommendations for cardiovascular prevention, a modified healthy lifestyle score was the sum of four components addressing use of smoking tobacco, physical activity, diet, and control of systolic blood pressure.

OUTCOMES

Cardiovascular and all-cause mortality.

ANALYTICAL APPROACH

Adjusted proportional hazards (aHRs) regression analyses with country as a random effect to estimate the associations between lifestyle score (low [0-2 points] as the referent, medium [3-5], and high [6-8]) and mortality. Associations were expressed as aHRs with 95% confidence intervals (CIs).

RESULTS

During a median of 3.8 years (17,451 person-years in total), there were 2,163 deaths, of which 826 were related to cardiovascular disease. Compared to patients with a low lifestyle score, the aHRs (95% CIs) for all-cause mortality among those with medium and high lifestyle scores were 0.75 (0.65-0.85) and 0.64 (0.54-0.76), respectively. Compared to patients with a low lifestyle score, the aHRs (95% CIs) for cardiovascular mortality among those with medium and high lifestyle scores were 0.73 (0.59-0.91) and 0.65 (0.49-0.85), respectively.

LIMITATIONS

Self-reported lifestyle, data-driven approach.

CONCLUSIONS

A healthier lifestyle is associated with lower all-cause and cardiovascular mortality among patients receiving maintenance hemodialysis.

Clinical events and patient-reported outcome measures during CKD progression: findings from the Chronic Renal Insufficiency Cohort Study

BACKGROUND

Patients with chronic kidney disease (CKD) face risks of not only end-stage kidney disease (ESKD), cardiovascular disease (CVD) and death, but also decline in kidney function, quality of life (QOL) and mental and physical well-being. This study describes the multidimensional trajectories of CKD using clinical events, kidney function and patient-reported outcome measures (PROMs). We hypothesized that more advanced CKD stages would associate with more rapid decline in each outcome.

METHODS

Among 3939 participants enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study, we evaluated multidimensional disease trajectories by G- and A-stages of enrollment estimated glomerular filtration rate (eGFR) and albuminuria, respectively. These trajectories included clinical events (ESKD, CVD, heart failure and death), eGFR decline and PROMs [kidney disease QOL (KDQOL) burden, effects and symptoms questionnaires, as well as the 12-item short form mental and physical component summaries]. We also evaluated a group-based multitrajectory model to group participants on the basis of longitudinal PROMs and compared group assignments by enrollment G- and A-stage.

RESULTS

The mean participant age was 58 years, 45% were women, mean baseline eGFR was 44 mL/min/1.73 m2 and median urine albumin:creatinine ratio was 52 mg/g. The incidence of all clinical events was greater and eGFR decline was faster with more advanced G- and A-stages. While baseline KDQOL and physical component measures were lower with more advanced G- and A-stage of CKD, changes in PROMs were inconsistently related to the baseline CKD stage. Groups formed on PROM trajectories were fairly distinct from existing CKD staging (observed agreement 60.6%) and were associated with the risk of ESKD, CVD, heart failure and death.

CONCLUSIONS

More advanced baseline CKD stage was associated with a higher risk of clinical events and faster eGFR decline, and was only weakly related to changes in patient-reported metrics over time.

Chronic kidney disease: prevalence and association with handgrip strength in a cross-sectional study

Background

Poor physical function is strongly associated with mortality and poor clinical outcomes in adults with chronic kidney disease (CKD). Handgrip strength (HGS) is an important index for physical function in the general population, and the association between HGS and CKD is worth investigating.

Methods

From September to November 2015, we conducted a cross-sectional study consisting of 10,407 participants in Jurong City, China. Age-related and sex-specific HGS percentile curves were constructed using the GAMLSS method. In addition, logistic regression was applied to estimate the association between HGS and the presence of CKD with odds ratios (ORs) and 95 % confidence intervals (CIs).

Results

Participants with low HGS tended to be older and were more likely to have CKD (8.73 %). Smoothed centile curves of HGS showed a similar shape in both sexes: participants peaked at approximately 20–35 years old and gradually decreased after the age of 50. In addition, independent of age and other factors, the decreased presence of CKD was significantly identified in individuals with moderate (OR: 0.64, 95 % CI: 0.49–0.83) and high HGS (OR: 0.37, 95 % CI: 0.23–0.58).

Conclusions

We concluded that HGS was significantly negatively associated with CKD in Chinese community-dwelling persons.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02452-5.

Association between physical activity and mortality in end-stage kidney disease: a systematic review of observational studies

BACKGROUND

End-stage Kidney Disease patients have a high mortality and hospitalization risk. The association of these outcomes with physical activity is described in the general population and in other chronic diseases. However, few studies examining this association have been completed in end-stage Kidney Disease patients, raising the need to systematically review the evidence on the association of physical activity with mortality and hospitalization in this population.

METHODS

Electronic databases (EBSCO, Scopus and Web of Science) and hand search were performed until March 2020 for observational studies reporting the association of physical activity with mortality or hospitalization in adult end-stage Kidney Disease patients on renal replacement therapy (hemodialysis, peritoneal dialysis and kidney transplant). Methodological quality of the included studies was assessed using the Quality in Prognosis Studies tool. The review protocol was registered in PROSPERO (CRD42020155591).

RESULTS

Eleven studies were included: six in hemodialysis, three in kidney transplant, and two in hemodialysis and peritoneal dialysis patients. Physical activity was self-reported, except in one study that used accelerometers. All-cause mortality was addressed in all studies and cardiovascular mortality in three studies. Nine studies reported a significant reduction in all-cause mortality with increased levels of physical activity. Evidence of a dose-response relationship was found. For cardiovascular mortality, a significant reduction was observed in two of the three studies. Only one study investigated the association of physical activity with hospitalization.

CONCLUSIONS

Higher physical activity was associated with reduced mortality in end-stage Kidney Disease patients. Future studies using objective physical activity measures could strengthen these findings. The association of physical activity with hospitalization should be explored in future investigations.

Exercise programme to improve quality of life for patients with end-stage kidney disease receiving haemodialysis: the PEDAL RCT

BACKGROUND

Whether or not clinically implementable exercise interventions in haemodialysis patients improve quality of life remains unknown.

OBJECTIVES

The PEDAL (PrEscription of intraDialytic exercise to improve quAlity of Life in patients with chronic kidney disease) trial evaluated the clinical effectiveness and cost-effectiveness of a 6-month intradialytic exercise programme on quality of life compared with usual care for haemodialysis patients.

DESIGN

We conducted a prospective, multicentre randomised controlled trial of haemodialysis patients from five haemodialysis centres in the UK and randomly assigned them (1 : 1) using a web-based system to (1) intradialytic exercise training plus usual-care maintenance haemodialysis or (2) usual-care maintenance haemodialysis.

SETTING

The setting was five dialysis units across the UK from 2015 to 2019.

PARTICIPANTS

The participants were adult patients with end-stage kidney disease who had been receiving haemodialysis therapy for > 1 year.

INTERVENTIONS

Participants were randomised to receive usual-care maintenance haemodialysis or usual-care maintenance haemodialysis plus intradialytic exercise training.

MAIN OUTCOME MEASURES

The primary outcome of the study was change in Kidney Disease Quality of Life Short Form, version 1.3, physical component summary score (from baseline to 6 months). Cost-effectiveness was determined using health economic analysis and the EuroQol-5 Dimensions, five-level version. Additional secondary outcomes included quality of life (Kidney Disease Quality of Life Short Form, version 1.3, generic multi-item and burden of kidney disease scales), functional capacity (sit-to-stand 60 and 10-metre Timed Up and Go tests), physiological measures (peak oxygen uptake and arterial stiffness), habitual physical activity levels (measured by the International Physical Activity Questionnaire and Duke Activity Status Index), fear of falling (measured by the Tinetti Falls Efficacy Scale), anthropometric measures (body mass index and waist circumference), clinical measures (including medication use, resting blood pressure, routine biochemistry, hospitalisations) and harms associated with intervention. A nested qualitative study was conducted.

RESULTS

We randomised 379 participants; 335 patients completed baseline assessments and 243 patients (intervention, n = 127; control, n = 116) completed 6-month assessments. The mean difference in change in physical component summary score from baseline to 6 months between the intervention group and control group was 2.4 arbitrary units (95% confidence interval -0.1 to 4.8 arbitrary units; p = 0.055). Participants in the intervention group had poor compliance (49%) and very poor adherence (18%) to the exercise prescription. The cost of delivering the intervention ranged from £463 to £848 per participant per year. The number of participants with harms was similar in the intervention (n = 69) and control (n = 56) groups.

LIMITATIONS

Participants could not be blinded to the intervention; however, outcome assessors were blinded to group allocation.

CONCLUSIONS

On trial completion the primary outcome (Kidney Disease Quality of Life Short Form, version 1.3, physical component summary score) was not statistically improved compared with usual care. The findings suggest that implementation of an intradialytic cycling programme is not an effective intervention to enhance health-related quality of life, as delivered to this cohort of deconditioned patients receiving haemodialysis.

FUTURE WORK

The benefits of longer interventions, including progressive resistance training, should be confirmed even if extradialytic delivery is required. Future studies also need to evaluate whether or not there are subgroups of patients who may benefit from this type of intervention, and whether or not there is scope to optimise the exercise intervention to improve compliance and clinical effectiveness.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN83508514.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 40. See the NIHR Journals Library website for further project information.

Randomized Trial-PrEscription of intraDialytic exercise to improve quAlity of Life in Patients Receiving Hemodialysis

Introduction

Whether clinically implementable exercise interventions in people receiving hemodialysis (HD) therapy improve health-related quality of life (HRQoL) remains unknown. The PrEscription of intraDialytic exercise to improve quAlity of Life (PEDAL) study evaluated the clinical benefit and cost-effectiveness of a 6-month intradialytic exercise program.

Methods

In a multicenter, single-blinded, randomized, controlled trial, people receiving HD were randomly assigned to (i) intradialytic exercise training (exercise intervention group [EX]) and (ii) usual care (control group [CON]). Primary outcome was change in Kidney Disease Quality of Life Short-Form Physical Component Summary (KDQOL-SF 1.3 PCS) from baseline to 6 months. Cost-effectiveness was determined using health economic analysis; physiological impairment was evaluated by peak oxygen uptake; and harms were recorded.

Results

We randomized 379 participants; 335 and 243 patients (EX n = 127; CON n = 116) completed baseline and 6-month assessments, respectively. Mean difference in change PCS from baseline to 6 months between EX and CON was 2.4 (95% confidence interval [CI]: -0.1 to 4.8) arbitrary units (P = 0.055); no improvements were observed in peak oxygen uptake or secondary outcome measures. Participants in the intervention group had poor compliance (47%) and poor adherence (18%) to the exercise prescription. Cost of delivering intervention ranged from US$598 to US$1092 per participant per year. The number of participants with harms was similar between EX (n = 69) and CON (n = 56). A primary limitation was the lack of an attention CON. Many patients also withdrew from the study or were too unwell to complete all physiological outcome assessments.

Conclusions

A 6-month intradialytic aerobic exercise program was not clinically beneficial in improving HRQoL as delivered to this cohort of deconditioned patients on HD.

Maintenance of Skeletal Muscle to Counteract Sarcopenia in Patients with Advanced Chronic Kidney Disease and Especially Those Undergoing Hemodialysis

Life extension in modern society has introduced new concepts regarding such disorders as frailty and sarcopenia, which has been recognized in various studies. At the same time, cutting-edge technology methods, e.g., renal replacement therapy for conditions such as hemodialysis (HD), have made it possible to protect patients from advanced lethal chronic kidney disease (CKD). Loss of muscle and fat mass, termed protein energy wasting (PEW), has been recognized as prognostic factor and, along with the increasing rate of HD introduction in elderly individuals in Japan, appropriate countermeasures are necessary. Although their origins differ, frailty, sarcopenia, and PEW share common components, among which skeletal muscle plays a central role in their etiologies. The nearest concept may be sarcopenia, for which diagnosis techniques have recently been reported. The focus of this review is on maintenance of skeletal muscle against aging and CKD/HD, based on muscle physiology and pathology. Clinically relevant and topical factors related to muscle wasting including sarcopenia, such as vitamin D, myostatin, insulin (related to diabetes), insulin-like growth factor I, mitochondria, and physical inactivity, are discussed. Findings presented thus far indicate that in addition to modulation of the aforementioned factors, exercise combined with nutritional supplementation may be a useful approach to overcome muscle wasting and sarcopenia in elderly patients undergoing HD treatments.

Cardiovascular and Renal Disease in Chronic Critical Illness

With advances in critical care, patients who would have succumbed in previous eras now survive through hospital discharge. Many survivors suffer from chronic organ dysfunction and induced frailty, representing an emerging chronic critical illness (CCI) phenotype. Persistent and worsening cardiovascular and renal disease are primary drivers of the CCI phenotype and have pathophysiologic synergy, potentiating one another and generating a downward spiral of worsening disease and clinical outcomes manifest as cardio-renal syndromes. In addition to pharmacologic therapies (e.g., diuretics, beta adrenergic receptor blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and blood pressure control), special consideration should be given to behavioral modifications that avoid the pitfalls of polypharmacy and suboptimal renal and hepatic dosing, to which CCI patients may be particularly vulnerable. Smoking cessation, dietary modifications (e.g., early high-protein nutrition and late low-sodium diets), and increased physical activity are advised. Select patients benefit from cardiac re-synchronization therapy or renal replacement therapy. Coordinated, patient-centered care bundles may improve compliance with standards of care and patient outcomes. Given the complex, heterogeneous nature of cardiovascular and renal disease in CCI and the dismal long-term outcomes, further research is needed to clarify pathophysiologic mechanisms of cardio-renal syndromes in CCI and develop targeted therapies.

Sex Difference in the Association between Physical Activity and All-Cause Mortality in Ambulatory Patients with Chronic Kidney Disease

(1) Background: The purpose of this article was to investigate the association between self-reported physical activity (PA) and all-cause mortality in ambulatory patients with chronic kidney disease (CKD), stage 4–5 including maintenance dialysis. (2) Methods: Ambulatory patients with CKD (eGFR < 30 mL/min/1.73 m²) with conservative treatment or chronic dialysis were included. PA was assessed using the Saltin–Grimby Physical Activity Level Scale. A Cox proportional hazards regression model––adjusted for age, sex, plasma–albumin, body mass index, socioeconomic status, and treatment––was applied. (3) Results: Participants (n = 374) were followed 39 ± 15 months from entry to death or censoring. Throughout the study period of 39 months, 156 deaths (42%) were registered. Regarding physical activity, 128 (34%) of the participants were inactive, 212 (57%) were moderately active, and 34 (9%) were highly or vigorously active. Moderate PA was associated with a decreased mortality risk in women (n = 150) compared to inactivity (HR 0.27 (0.15; 0.51), p < 0.001), whereas a high/vigorous level of PA was not significantly associated with mortality risk compared to inactivity. In men (n = 224), the associations between PA levels and mortality risk were not significant. (4) Conclusions: Moderate PA was associated with reduced all-cause mortality in ambulatory women with stage 4–5 CKD with or without maintenance dialysis treatment. Physical activity was not significantly associated with mortality in men.

Understanding the Impact of Initial COVID-19 Restrictions on Physical Activity, Wellbeing and Quality of Life in Shielding Adults with End-Stage Renal Disease in the United Kingdom Dialysing at Home versus In-Centre and Their Experiences with Telemedicine

Early in the coronavirus-2019 (COVID-19) containment strategy, people with end-stage renal disease (ESRD) were identified as extremely clinically vulnerable and subsequently asked to 'shield' at home where possible. The aim of this study was to investigate how these restrictions and the transition to an increased reliance on telemedicine within clinical care of people living with kidney disease impacted the physical activity (PA), wellbeing and quality of life (QoL) of adults dialysing at home (HHD) or receiving in-centre haemodialysis (ICHD) in the UK. Individual semistructured telephone interviews were conducted with adults receiving HHD (n = 10) or ICHD (n = 10), were transcribed verbatim and, subsequently, thematically analysed. As result of the COVID-19 restrictions, PA, wellbeing and QoL of people with ESRD were found to have been hindered. However, widespread support for the continued use of telemedicine was strongly advocated and promoted independence and satisfaction in patient care. These findings highlight the need for more proactive care of people with ESRD if asked to shield again, as well as increased awareness of safe and appropriate PA resources to help with home-based PA and emotional wellbeing.

Seasonal variations in nutritional status and oxidative stress in patients on hemodialysis: Are they related?

OBJECTIVE

Seasonal variations in body composition and parameters that reflect nutritional status are well established in patients on hemodialysis (HD). However, to our knowledge, no study has assessed the changes in oxidative stress (OS). The aims of this study were to assess seasonal variations in OS, body composition, and other nutritional parameters.

METHODS

Seasonal variations in fat tissue mass (FTM), fat tissue index (FTI), adipose tissue mass (ATM), lean tissue mass (LTM), lean tissue index (LTI), body cell mass (BCM), overhydration (OH) volume, and OS (blood levels of derivatives of reactive oxygen metabolites [d-ROMs], thiobarbituric reactive substances, plasma protein reduced thiol content [THIOLS], and ferric reducing ability of plasma) were assessed in 45 patients on HD, 70 y of age (60.5-76.5 y).

RESULTS

FTM (P < 0.001), FTI (P < 0.001), and ATM (P < 0.001) significantly increased, whereas LTI (P < 0.001), LTM (P < 0.001), BCM (P < 0.001), and OH volume (P = 0.004) significantly decreased over the season. Additionally, significant seasonal variations in the levels of d-ROMs (P = 0.02) and THIOLS (P = 0.02) were found. Levels of d-ROMs were found to be a significant predictor of LTM and BCM (β = -0.57; 95% confidence interval [CI], -1.08 to -0.06; P = 0.03; β = -0.04; 95% CI, -0.075 to -0.006; P = 0.02). Furthermore, hip circumference was found to be the most significant predictor of the level of d-ROMs (β = 2.66; 95% CI; 0.28-5.04; P = 0.03) and waist-to-height ratio (β = 251; 95% CI, 16.6-477.2; P = 0.03) and serum prealbumin levels of THIOLS (β = 263; 95% CI, 6.8-521.1; P = 0.04).

CONCLUSION

These results suggest seasonal variations in OS in patients on HD and a possible interaction between OS and nutritional status in these patients.

A Systematic Review of Scope and Consistency of Outcome Measures for Physical Fitness in Chronic Kidney Disease Trials

Introduction

Impaired physical fitness is prevalent in people with chronic kidney disease (CKD), associating with an increased risk of mortality, falls, and hospitalization. A plethora of physical fitness outcomes have been reported in randomized trials. This study aimed to assess the scope and consistency of physical fitness outcomes and outcome measures reported in trials in CKD.

Methods

A systematic review of randomized trials reporting physical fitness outcomes in adults with CKD (not requiring kidney replacement therapy) receiving hemodialysis (HD) or peritoneal dialysis and kidney transplant recipients was conducted. Studies were identified from MEDLINE, Embase, and the Cochrane Library from 2000 to 2019. The scope, frequency, and characteristics of outcome measures were categorized and analyzed.

Results

From 111 trials, 87 tests/measurements were used to evaluate 30 outcomes measures that reported on 23 outcomes, categorized into five domains of physical fitness: neuromuscular fitness (reported in 76% of trials), exercise capacity (64%), physiological-metabolic (49%), body composition (36%), and cardiorespiratory fitness (30%). Neuromuscular fitness was examined by 37 tests/measurements including the physical function component of questionnaires (27%), one-repetition maximum (9%), and hand-grip strength (9%). Outcome measures were assessed by lab-based (58% of all trials), field-based (31%), and patient-reported measures (11%), and commonly evaluated at 12 (30%), 26 (23%) and 52 weeks (10%), respectively.

Conclusion

There is large heterogeneity in the reporting of physical fitness outcomes, with inconsistencies particularly in the definitions of outcome measures. Standardization in the assessment of physical fitness will likely improve the comparability of trial outcomes and enhance clinical recommendations.

Association of Physical Activity and Poor Health Outcomes in Patients With Advanced CKD

RATIONALE & OBJECTIVE

Chronic kidney disease (CKD) is associated with declining physical function and activity. In the general population, lower physical activity is associated with poorer quality of life and greater all-cause mortality. The aim of this study was to assess if lower physical activity levels are associated with adverse health outcomes in patients with advanced CKD.

STUDY DESIGN

A multicenter prospective cohort study.

SETTING & PARTICIPANTS

579 adult patients with CKD glomerular filtration rate categories 4 and 5 (G4-G5) treated at 4 Canadian multidisciplinary kidney health clinics between 2012 and 2018.

EXPOSURE

Patient-reported measures of physical activity using the Physical Activity Scale for the Elderly (PASE) questionnaire and subsequently stratified PASE scores into tertiles.

OUTCOME

All-cause mortality, progression to kidney failure, and future falls.

ANALYTICAL APPROACH

Outcomes were analyzed using time-dependent proportional hazards models and logistic regression models.

RESULTS

In 1,193 days of follow-up observation, 118 patients died, 204 progressed to dialysis, and 129 reported a fall. When compared with low physical activity, higher levels of physical activity were associated with a 52% lower all-cause mortality (adjusted HR, 0.48; 95% CI, 0.27-0.85) in models adjusted for age, sex, and comorbidity. No associations were detected between higher levels of physical activity and either slower progression to kidney failure or a lower rate of future falls.

LIMITATIONS

Physical activity and falls were self-reported. Our population was of limited racial/ethnic diversity, which may affect generalizability. Findings were observational and do not indicate whether interventions targeting physical activity may affect adverse health outcomes.

CONCLUSIONS

Higher levels of physical activity were associated with about 50% lower all-cause mortality in the advanced CKD population. These findings are consistent with a potential benefit from maintained physical activity as patients approach kidney failure.

Associations of Performance-Based Functional Assessments and Adverse Outcomes in CKD

Background

The comparative utility of performance-based functional assessments in predicting adverse outcomes in CKD is unknown. To examine their relative utility, we examined three performance-based functional assessments in an observational cohort of patients with CKD.

Methods

We recruited 350 participants with stage II-V, predialysis CKD. Participants were administered three performance-based functional assessments: Short Physical Performance Battery (SPPB), Modified Mini-Mental Status Exam (M3SE), and Lawton Instrumental Activities of Daily Living (IADL). Scores were dichotomized on the basis of the median and combined into a summary score. Outcomes included 50% GFR reduction, ESKD, and death. We used Cox proportional hazards to assess the association of performance-based functional assessments with outcomes.

Results

Compared with high performers, low SPPB performers had the highest adjusted rate of death, ESKD, or 50% reduction in GFR (HR, 1.96; 95% CI, 1.28 to 2.99). Low SPPB had the strongest association with death when adjusted for multiple covariates (HR, 2.43; 95% CI, 1.36 to 4.34). M3SE performance was not associated with any adverse outcome. None of the performance-based functional assessments were associated with ESKD, but a low IADL score was associated with a lower hazard ratio for ESKD or 50% decline GFR (HR, 0.49; 95% CI, 0.24 to 1.00).

Conclusions

Low SPPB score was the strongest predictor of death and all adverse outcomes as a composite. Future trials should determine if outcomes for patients with CKD who have poor physical performance and low SPPB scores are improved by targeted interventions.

Clinical Trial registry name and registration number

Safe Kidney Care Cohort Study, NCT01407367.

Energy expenditure estimates in chronic kidney disease using a novel physical activity questionnaire

BACKGROUND

Physical activity (PA) levels are low in patients with advanced chronic kidney disease (CKD), and associate with increased morbidity and mortality. Reliable tools to assess PA in CKD are scarce. We aimed to develop and validate a novel PA questionnaire for use in CKD (CKD-PAQ).

METHODS

In phase 1, a prototype questionnaire was developed based on the validated Recent Physical Activity Questionnaire (RPAQ). Structured feedback on item relevance and clarity was obtained from 40 CKD patients. In phase 2, the questionnaire was refined in 3 iterations in a total of 226 CKD patients against 7-day accelerometer and RPAQ measurements. In phase 3, the definitive CKD-PAQ was compared with RPAQ in 523 CKD patients.

RESULTS

In the final iteration of phase 2, CKD-PAQ data were compared to accelerometer-derived and RPAQ data in 60 patients. Mean daily Metabolic Equivalent of Task (MET) and Total Energy Expenditure (TEE) levels were similar by all methods. Intraclass correlation coefficients showed fair agreement (MET) and good (TEE) between accelerometry and both CKD-PAQ and RPAQ. Agreement between questionnaires was excellent. For mean daily MET bias was 0.035 (SD 0.312) for CKD-PAQ and 0.018 (SD 0.326) for RPAQ. For TEE bias was 91 (SD 518) for CKD-PAQ and 44 (SD 548) kcal for RPAQ. Limits of agreement were wide for both parameters, with less dispersion of CKD-PAQ values. In phase 3, agreement between questionnaires was good (MET) and excellent (TEE). Bias of CKD-PAQ-derived mean daily MET from RPAQ-derived values was 0.031 (SD 0.193) with 95% limits of agreement -0.346 to 0.409. Corresponding values for TEE were 48 (SD 325) and -588 to 685 kcal/day. CKD-PAQ appeared to improve discrimination between low activity groups.

CONCLUSIONS

CKD-PAQ performs comparably to RPAQ though is shorter, easier to complete, may better capture low level activity and improve discrimination between low-activity groups.

Effects of intradialytic cycling exercise on daily physical activity, physical fitness, body composition, and clinical parameters in high-volume online hemodiafiltration patients: a pilot randomized-controlled trial

PURPOSE

The mortality of dialysis patients treated with high-volume online hemodiafiltration (OL-HDF) is better than hemodialysis, but is still higher than healthy population. Low daily physical activity increases cardiovascular mortality. Addition of intradialytic exercise (IDX) program might improve physical activity and health status in OL-HDF patients. This pilot open-labeled randomized-controlled trial was conducted to evaluate the effects of IDX on physical activity and other clinical parameters in OL-HDF patients.

METHODS

Twelve OL-HDF patients were randomized into control (n = 6) or IDX (n = 6) groups. The subjects in IDX group were trained to exercise using a cycle ergometer for 60 min during each OL-HDF session. Physical activity measured as daily step count using a wrist-worn triaxial accelerometer, physical fitness, or cardiorespiratory fitness assessed by VO₂max and other physical performance tests, lean body mass determined by the Dual-energy X-ray absorptiometry (DXA), quality of life (QOL), and various parameters were compared between baseline and 6 months.

RESULTS

The baseline physical activity status was comparable. Following 6-month IDX, the physical activity was significantly improved in IDX group [+ 1048.79 (+ 741.50, + 2792.54) vs. - 362.06 (- 1626.82, - 167.47) steps/day, p = 0.01], while physical fitness and QOL were unchanged. The lean body mass parameters were preserved in the IDX group while seemed to decrease in the control group. Serum albumin was significantly increased in the IDX group (p = 0.01). The hemoglobin changes were significantly better (p = 0.01) and the erythropoietin resistance index was significantly lower in the IDX group (p = 0.03). Phosphate reduction was significantly greater in the IDX group (p = 0.04).

CONCLUSIONS

IDX could improve physical activity and other metabolic parameters in OL-HDF patients and these might contribute to further improvement in clinical and survival outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Registration: NCT03353844.

The PrEscription of intraDialytic exercise to improve quAlity of Life in patients with chronic kidney disease trial: study design and baseline data for a multicentre randomized controlled trial

Background

Exercise interventions designed to improve physical function and reduce sedentary behaviour in haemodialysis (HD) patients might improve exercise capacity, reduce fatigue and lead to improved quality of life (QOL). The PrEscription of intraDialytic exercise to improve quAlity of Life study aimed to evaluate the effectiveness of a 6-month intradialytic exercise programme on QOL and physical function, compared with usual care for patients on HD in the UK.

Methods

We conducted a prospective, pragmatic multicentre randomized controlled trial in 335 HD patients and randomly (1:1) assigned them to either (i) intradialytic exercise training plus usual care maintenance HD or (ii) usual care maintenance HD. The primary outcome of the study was the change in Kidney Disease Quality of Life Short Form (KDQOL-SF 1.3) Physical Component Score between baseline and 6 months. Additional secondary outcomes included changes in peak aerobic capacity, physical fitness, habitual physical activity levels and falls (International Physical Activity Questionnaire, Duke’s Activity Status Index and Tinetti Falls Efficacy Scale), QOL and symptom burden assessments (EQ5D), arterial stiffness (pulse wave velocity), anthropometric measures, resting blood pressure, clinical chemistry, safety and harms associated with the intervention, hospitalizations and cost-effectiveness. A nested qualitative study investigated the experience and acceptability of the intervention for both participants and members of the renal health care team.

Results

At baseline assessment, 62.4% of the randomized cohort were male, the median age was 59.3 years and 50.4% were white. Prior cerebrovascular events and myocardial infarction were present in 8 and 12% of the cohort, respectively, 77.9% of patients had hypertension and 39.4% had diabetes. Baseline clinical characteristics and laboratory data for the randomized cohort were generally concordant with data from the UK Renal Registry.

Conclusion

The results from this study will address a significant knowledge gap in the prescription of exercise interventions for patients receiving maintenance HD therapy and inform the development of intradialytic exercise programmes both nationally and internationally.

Trial Registration

ISRCTN N83508514; registered on 17 December 2014.

Accelerometer-measured physical activity and functional behaviours among people on dialysis

BACKGROUND

The feasibility of wrist-worn accelerometers, and the patterns and determinants of physical activity, among people on dialysis are uncertain.

METHODS

People on maintenance dialysis were fitted with a wrist-worn AxivityAX3 accelerometer. Subsets also wore a 14-day electrocardiograph patch (Zio^®PatchXT) and wearable cameras. Age-, sex- and season-matched UK Biobank control groups were derived for comparison.

RESULTS

Median (interquartile range) accelerometer wear time for the 101 recruits was 12.5 (10.4-13.5) days, of which 73 participants (mean age 66.5 years) had excellent wear on both dialysis and non-dialysis days. Mean (standard error) overall physical activity levels were 15.5 (0.7) milligravity units (mg), 14.8 (0.7) mg on dialysis days versus 16.2 (0.8) mg on non-dialysis days. This compared with 28.1 (0.5) mg for apparently healthy controls, 23.4 (0.4) mg for controls with prior cardiovascular disease (CVD) and/or diabetes mellitus and 22.9 (0.6) mg for heart failure controls. Each day, we estimated that those on dialysis spent an average of about 1 hour (h/day) walking, 0.6 h/day engaging in moderate-intensity activity, 0.7 h/day on light tasks, 13.2 h/day sedentary and 8.6 h/day asleep. Older age and self-reported leg weakness were associated with decreased levels of physical activity, but the presence of prior CVD, arrhythmias and listing for transplantation were not.

CONCLUSIONS

Wrist-worn accelerometers are an acceptable and reliable method to measure physical activity in people on dialysis and may also be used to estimate functional behaviours. Among people on dialysis, who are broadly half as active as general population controls, age and leg weakness appear to be more important determinants of low activity levels than CVD.

The dominant prognostic value of physical functioning among quality of life domains in end-stage kidney disease

BACKGROUND

The prognostic relevance of health-related quality of life (HRQoL) has been scarcely studied in the dialysis population and the prognostic power for mortality of the HRQoL domains is unknown.

METHODS

We tested the prognostic value for mortality of the HRQoL domains included in the 36-item Short Form Health Survey (SF-36) by Cox's regression analysis and by state-of-the-art prognostic techniques {explained variation in mortality [R2], calibration, discrimination [Harrell's C], risk reclassification [Net Reclassification Index (NRI)], Integrated Discrimination Index [IDI]} in a cohort of 951 patients on chronic haemodialysis.

RESULTS

In multivariable Cox models, all but two domains (role limitation due to physical health and due to emotional problems) were independently related with mortality. Physical functioning was the domain adding the highest explanatory power (R2+5.3%) to a basic model including established risk factors for mortality in the dialysis population. The same domain improved risk calibration and showed the highest Harrell's C (+1.7%) and the highest reclassification power (categorical NRI + 8.7%, continuous NRI +46%, P ≤ 0.006) and the highest IDI (+3.4%, P < 0.001). These results were fully confirmed in analyses testing the additional prognostic power of SF-36 domains when combined to a well-validated risk score in dialysis patients.

CONCLUSIONS

Physical functioning holds the highest prognostic power for mortality among the domains of SF-36. The gain in prognostic ability by this domain is relevant for clinical practice. Physical functioning has the potential for refining the prognosis and for informing exercise programmes in the dialysis population.

Daily physical activity in patients on chronic haemodialysis and its relation with fatigue and depressive symptoms

OBJECTIVE

Fatigue and depressed mood are considered main impediments to physical activity in haemodialysis (HD) patients. A better understanding of their interrelationships is crucial to develop effective therapies. Moreover, measurement of daily physical activity (DPA) in HD patients is tricky, as it is usually assessed by subjective self-report questionnaires. Therefore, we aimed to objectively measure sponteanous DPA with motion sensors and to explore its relation with fatigue and depressive symptoms.

METHODS

DPA was assessed for seven consecutive days in 37 HD patients based on their daily step count measured with the SenseWear™ Armband. The Fatigue Severity Scale (FSS) and Beck Depression Inventory-II (BDI-II) were administered to evaluate fatigue and depressed mood.

RESULTS

Median DPA was 2424 steps/day, (IQR:892-4545). In 81% of subjects, DPA felt within a sedentary lifestyle classification, as they made < 5.000 steps/day. DPA did not correlate with fatigue (r_s = 0.04, p = 0.832), and did not significantly differ between patients categorized as clinically fatigued (n = 23, FSS ≥ 4) or not (n = 14, FSS < 4) (p = 0.654, d = 0.20). Although low-depressed subjects (n = 19, BDI-II ≤ 13) made on average 1.7 times more steps/day than high-depressed subjects (n = 18, BDI-II > 13) (p = 0.111, d = 0.60), depressive mood did also not correlate significantly with DPA (r_s = - 0.23, p = 0.175).

CONCLUSION

Objective assessment of DPA with motion sensors is feasible in HD patients and allows identifying a sedentary lifestyle. Our results suggest that spontanous DPA is determined by age rather than by fatigue or mood.

Disability of Dialysis Patients and the Condition of Blood Vessels

The number of elderly hemodialysis patients is constantly increasing worldwide. This population has a high burden of comorbid conditions, which impair daily activities. The aim of the study was to analyze problems of disability in hemodialysis patients in the context of cardiovascular (CV) complications and vascular condition. In this cross-sectional study, 129 patients (mean age 64.5) were enrolled. The degree of disability in Barthel index (Bi) and 10-year cardiovascular risk (QRISK®3) were assessed. A Mobil-O-Graph monitor was used for measuring hemodynamic parameters. Only 6.2% of patients were professionally active, 19% used a wheelchair for transport, and 16% used crutches. More than half (51%) were independent in everyday activities reaching 80-100 points on Bi. The rest, with Bi < 80, were considered as dependent. The most common causes of disability were CV complications. The independent group (80-100 points) was characterized by significantly lower pulse wave velocity (PWV) and lower QRISK®3 compared to dependent patients. The degree of disability negatively correlated with age, PWV, and QRISK®3. Multivariate logistic regression revealed that disability (Bi < 80) was independently associated with CV events in the past adjusted odds ratio (adj.OR) 4.83 (95% confidence interval (95% CI): 1.74-13.41) and higher PWV adj.OR 1.45 (95% CI: 1.15-1.82). Our results indicate that CV diseases are the most important cause of functional impairment.

Impact of physical exercise in patients with chronic kidney disease: Sistematic review and meta-analysis

Physical exercise may offer multiple benefits to patients with chronic kidney disease (CKD). However, it was not traditionally recommended because of the possibility of impairing renal function and increasing proteinuria. The objective of this study is to review the clinical trials on physical exercise in patients with CKD and describe its effect on the progression of kidney disease and other factors associated. Randomized clinical trials (RCT) comparing an intervention that included an exercise component with a control group without physical exercise in non-dialysis patients with CKD from 2007 to 2018 in English and Spanish were included. PubMed, Scopus, Embase, Ovid (Medline) and PEDro databases were used for the search. Effects of physical exercise were summarized by the standardized mean difference (SMD). No differences were found in glomerular filtration rate or proteinuria between the intervention group and the control group: SMD -0.3 (P=.81); SMD 26.6 (P=.82). Positive effects were obtained on peak oxygen consumption: SMD 2.5 (P<.001), functional capacity: SMD 56.6 (P<.001), upper limb strength: SMD 6.8 (P<.001) and hemoglobin: SMD 0.3 (P=.003). An improvement on the quality of life was also evident using the KDQOL-36 survey: SMD 3.56 (P=.02) and the SF-36 survey: SMD 6.66 (P=.02). In conclusion, the practice of low-intensity physical exercise routinely has no negative impact on renal function. On the contrary, it improves aerobic and functional capacity, impacting positively on the quality of life.

Intradialytic neuromuscular electrical stimulation improves functional capacity and muscle strength in people receiving haemodialysis: a systematic review

QUESTIONS

Does neuromuscular electrical stimulation (NMES) applied during haemodialysis sessions improve functional capacity in people with end-stage renal disease? Does NMES used in this way also improve muscle strength, muscle mass/architecture, psychological outcomes, cardiovascular outcomes and biochemical variables? Does it have any adverse effects?

DESIGN

Systematic review of randomised controlled trials with meta-analysis. PubMed, Web of Science, Scopus and SPORTDiscus were searched from inception to 15 October 2019.

PARTICIPANTS

Patients receiving haemodialysis for end-stage renal disease.

INTERVENTION

NMES administered during haemodialysis sessions versus control.

OUTCOMES MEASURES

Functional capacity, muscle strength, muscle mass, psychological outcomes, cardiovascular outcomes, biochemical variables and adverse events.

DATA ANALYSIS

Data were meta-analysed where possible and results were expressed as the pooled mean difference between groups with a 95% confidence interval.

RESULTS

Eight studies (221 patients) were included in the analysis. Overall, the methodological quality of the studies was fair to good. NMES improved functional capacity as assessed by the 6-minute walk distance test (MD 31 m, 95% CI 13 to 49) and peak workload attained in incremental exercise (MD 12.5 W, 95% CI 3.2 to 21.9). NMES increased knee extensor muscle strength (MD 3.5 kg, 95% CI 2.3 to 4.7) and handgrip strength (MD 2.4 kg, 95% CI 0.4 to 4.4). Muscle mass/architecture was not substantially affected. NMES was estimated to be beneficial for several domains of quality of life in several studies, although most of these estimates were imprecise. No benefits were found for cardiovascular outcomes. The available data did not establish any clear effects on cardiovascular outcomes or biochemical variables (dialysis efficiency, urea and creatinine). No major NMES-related adverse events were observed.

CONCLUSIONS

NMES is safe, practical and effective for improving functional capacity and muscle strength in haemodialysis patients. Further research is needed to confirm the clinical relevance of these findings.

REGISTRATION

PROSPERO CRD42018107323.

Frailty Screening in Chronic Kidney Disease: Current Perspectives

Frailty has been defined as a state of increased vulnerability as a consequence of deficit accumulation. Frailty screening has not yet been widely implemented into routine nephrology care. Patients with chronic kidney disease (CKD) are at high risk of being frail, and frailty has been associated with worse outcomes in this population. Standard management of CKD, including initiation of renal replacement therapies, may have decreased benefit or potentially cause harm in the presence of frailty, and a variety of interventions for modifying frailty in the CKD population have been proposed. The optimal means of screening for frailty in patients with kidney disease remains unclear. This review highlights the value of frailty screening in CKD by summarizing the outcomes associated with frailty and exploring proposed changes to the management of frail patients with CKD. Finally, we will propose a framework for how to implement frailty screening into standard nephrology care.

Standardising the measurement of physical activity in people receiving haemodialysis: considerations for research and practice

BACKGROUND

Physical activity (PA) is exceptionally low amongst the haemodialysis (HD) population, and physical inactivity is a powerful predictor of mortality, making it a prime focus for intervention. Objective measurement of PA using accelerometers is increasing, but standard reporting guidelines essential to effectively evaluate, compare and synthesise the effects of PA interventions are lacking. This study aims to (i) determine the measurement and processing guidance required to ensure representative PA data amongst a diverse HD population, and; (ii) to assess adherence to PA monitor wear amongst HD patients.

METHODS

Clinically stable HD patients from the UK and China wore a SenseWear Armband accelerometer for 7 days. Step count between days (HD, Weekday, Weekend) were compared using repeated measures ANCOVA. Intraclass correlation coefficients (ICCs) determined reliability (≥0.80 acceptable). Spearman-Brown prophecy formula, in conjunction with a priori ≥  80% sample size retention, identified the minimum number of days required for representative PA data.

RESULTS

Seventy-seven patients (64% men, mean ± SD age 56 ± 14 years, median (interquartile range) time on HD 40 (19-72) months, 40% Chinese, 60% British) participated. Participants took fewer steps on HD days compared with non-HD weekdays and weekend days (3402 [95% CI 2665-4140], 4914 [95% CI 3940-5887], 4633 [95% CI 3558-5707] steps/day, respectively, p < 0.001). PA on HD days were less variable than non-HD days, (ICC 0.723-0.839 versus 0.559-0.611) with ≥ 1 HD day and ≥  3 non-HD days required to provide representative data. Using these criteria, the most stringent wear-time retaining ≥ 80% of the sample was ≥7 h.

CONCLUSIONS

At group level, a wear-time of ≥7 h on ≥1HD day and ≥ 3 non-HD days is required to provide reliable PA data whilst retaining an acceptable sample size. PA is low across both HD and non- HD days and future research should focus on interventions designed to increase physical activity in both the intra and interdialytic period.

Renal Association Clinical Practice Guideline on Haemodialysis

This guideline is written primarily for doctors and nurses working in dialysis units and related areas of medicine in the UK, and is an update of a previous version written in 2009. It aims to provide guidance on how to look after patients and how to run dialysis units, and provides standards which units should in general aim to achieve. We would not advise patients to interpret the guideline as a rulebook, but perhaps to answer the question: "what does good quality haemodialysis look like?"The guideline is split into sections: each begins with a few statements which are graded by strength (1 is a firm recommendation, 2 is more like a sensible suggestion), and the type of research available to back up the statement, ranging from A (good quality trials so we are pretty sure this is right) to D (more like the opinion of experts than known for sure). After the statements there is a short summary explaining why we think this, often including a discussion of some of the most helpful research. There is then a list of the most important medical articles so that you can read further if you want to - most of this is freely available online, at least in summary form.A few notes on the individual sections: 1. This section is about how much dialysis a patient should have. The effectiveness of dialysis varies between patients because of differences in body size and age etc., so different people need different amounts, and this section gives guidance on what defines "enough" dialysis and how to make sure each person is getting that. Quite a bit of this section is very technical, for example, the term "eKt/V" is often used: this is a calculation based on blood tests before and after dialysis, which measures the effectiveness of a single dialysis session in a particular patient. 2. This section deals with "non-standard" dialysis, which basically means anything other than 3 times per week. For example, a few people need 4 or more sessions per week to keep healthy, and some people are fine with only 2 sessions per week - this is usually people who are older, or those who have only just started dialysis. Special considerations for children and pregnant patients are also covered here. 3. This section deals with membranes (the type of "filter" used in the dialysis machine) and "HDF" (haemodiafiltration) which is a more complex kind of dialysis which some doctors think is better. Studies are still being done, but at the moment we think it's as good as but not better than regular dialysis. 4. This section deals with fluid removal during dialysis sessions: how to remove enough fluid without causing cramps and low blood pressure. Amongst other recommendations we advise close collaboration with patients over this. 5. This section deals with dialysate, which is the fluid used to "pull" toxins out of the blood (it is sometimes called the "bath"). The level of things like potassium in the dialysate is important, otherwise too much or too little may be removed. There is a section on dialysate buffer (bicarbonate) and also a section on phosphate, which occasionally needs to be added into the dialysate. 6. This section is about anticoagulation (blood thinning) which is needed to stop the circuit from clotting, but sometimes causes side effects. 7. This section is about certain safety aspects of dialysis, not seeking to replace well-established local protocols, but focussing on just a few where we thought some national-level guidance would be useful. 8. This section draws together a few aspects of dialysis which don't easily fit elsewhere, and which impact on how dialysis feels to patients, rather than the medical outcome, though of course these are linked. This is where home haemodialysis and exercise are covered. There is an appendix at the end which covers a few aspects in more detail, especially the mathematical ideas. Several aspects of dialysis are not included in this guideline since they are covered elsewhere, often because they are aspects which affect non-dialysis patients too. This includes: anaemia, calcium and bone health, high blood pressure, nutrition, infection control, vascular access, transplant planning, and when dialysis should be started.

Effects of intradialytic cycling exercise on exercise capacity, quality of life, physical function and cardiovascular measures in adult haemodialysis patients: a systematic review and meta-analysis

Background

Intradialytic cycling (IDC), delivered during haemodialysis (HD), has the potential to improve many health issues. This systematic review and meta-analysis examine the evidence on the effects of IDC on exercise capacity, quality of life (QoL), physical function and cardiovascular health.

Methods

Twenty-four databases were searched alongside Internet and hand searching, and consultation with experts. Eligibility criteria were cluster randomized, randomized and quasi-randomized controlled trials (RCTs) of IDC versus usual care in prevalent adult HD patients. Primary outcome measures were exercise capacity (VO2 peak and field tests) and QoL. Secondary measures were cardiac and physical function.

Results

Thirteen RCTs were eligible. Eight provided data for use in meta-analyses, which indicated no significant change in VO2 peak (mean difference, MD 1.19 mL/kg/min, 95% confidence interval -1.15 to 3.52, P = 0.3), physical (mean change, MC 1.97, -8.27 to 12.22, P = 0.7) or mental component (MC 3.37, -7.94 to 14.68, P = 0.6) summary scores of the Medical Outcomes Short Form 36, pulse wave velocity (MD -0.57 m/s, -1.55 to 0.41, P = 0.4), systolic (MD -2.28 mmHg, -14.46 to 9.90, P = 0.7) or diastolic blood pressure (MD 2.25 mmHg, -3.01 to 7.50, P = 0.4) following IDC. IDC, however, leads to an improvement in performance on the 6-min walk test (MD 87.84 m, 39.60-136.09, P = 0.0004). All included studies were considered to have high risk of bias.

Conclusions

There is insufficient evidence demonstrating whether cycling exercise during HD improves patient outcomes. High-quality, adequately powered RCTs of IDC are required.

A Location-Based Objective Assessment of Physical Activity and Sedentary Behavior in Ambulatory Hemodialysis Patients

Background:

Dialysis patients have reduced moderate to vigorous physical activity, and light physical activity. This has been shown in self-reported surveys and objective accelerometer studies. Less attention has been directed toward sedentary behavior, which is characterized by low energy expenditure (≤1.5 metabolic equivalents). Furthermore, locations where physical activity and sedentary behavior occur are largely unknown for dialysis patients.

Objectives:

The objectives of this study were (1) to determine the minutes per day of moderate to vigorous physical activity, light physical activity, and sedentary behavior for hemodialysis patients; (2) to describe differences in moderate to vigorous physical activity, light physical activity, and sedentary behavior comparing dialysis versus nondialysis days; and (3) to describe the locations where moderate to vigorous physical activity, light physical activity, and sedentary behavior occur using global positioning system (GPS) data.

Design:

Cross-sectional study.

Setting:

The study was performed at a tertiary care hospital in Nova Scotia, Canada.

Patients:

A total of 50 adult in-center hemodialysis patients consented to the study.

Measurements:

Physical activity and sedentary behavior were measured with an Actigraph-GT3X accelerometer. Location was determined using a Qstarz BT-Q1000X GPS receiver.

Methods:

Minutes of daily activity were described as was percentage of wear time for each activity level across different locations during waking hours. Physical activity intensity, quantity, and location were also analyzed according to dialysis vs nondialysis days.

Results:

Forty-three patients met requirements for accelerometer analysis, of whom 42 had GPS data. Median wear time was 836.5 min/day (interquartile range [IQR]: 788.3-918.3). Median minutes of daily wear time spent in sedentary behavior, light physical activity, and moderate to vigorous physical activity was 636 minutes (IQR: 594.1-730.1), 178 minutes (IQR: 144-222.1), and 1.6 minutes (IQR: 0.6-7.7), respectively. Proportion of daily wear time spent in sedentary behavior, light physical activity, and moderate to vigorous physical activity was 78.4% (IQR: 70.7-84.0), 21.5% (IQR: 16.0-26.9), and 0.2% (IQR: 0.1-1.1), respectively. Home was the dominant location for total linked accelerometer-GPS time (59.4%, IQR: 46.9-69.5) as well as for each prespecified level of activity. Significantly more sedentary behavior and less light physical activity occurred on dialysis days compared with nondialysis days (P ≤ .01, respectively). Moderate to vigorous physical activity did not differ significantly between dialysis and nondialysis days.

Limitations:

Small sample size from a single academic center may limit generalizability. Difficult to engage population as less than half of eligible dialysis patients provided consent. Physical activity may have been underestimated as devices were not worn for all waking hours or aquatic activities, and hip-based accelerometers may not capture stationary exercise.

Conclusions:

Ambulatory, in-center hemodialysis patients exhibit substantial sedentary behavior and minimal physical activity across a limited range of locations. Given the sedentary tendencies of this population, focus should be directed on increasing physical activity at any location frequented. Home-based exercise programs may serve as a potential adjunct to established intradialytic-based therapies given the amount of time spent in the home environment.

The Effect of Health-Related Behaviors on Disease Progression and Mortality in Early Stages of Chronic Kidney Disease: A Korean Nationwide Population-Based Study

A healthy life style is associated with decreased risk of chronic kidney disease (CKD) and mortality in the general population. However, there is no definitive evidence of the benefits of physical activity and other health-related behaviors in the early-stage of CKD. This study aimed to explore the association between health-related behaviors and end-stage renal disease (ESRD) and mortality in the early stages of CKD. The National Health Insurance Service (NHIS) database from 1 January 2009 to 31 December 2016 was used to screen 83,470 subjects with early stage CKD. Cox proportional hazard regression analysis was used to evaluate the association between health-related behaviors and ESRD and death. Kaplan–Meier curves for mortality and ESRD were plotted according to the physical activity, smoking status, and alcohol consumption pattern. Risk of death decreased significantly in subjects who engaged in sufficient physical activity (adjusted Hazard Ratio (HR) 0.73; 95% CI: 0.64–0.83; p < 0.001). Risk of ESRD and death increased significantly in the current smoker with adjusted HR of 1.44 (95% CI: 1.06–1.95; p < 0.02) and 1.61 (95% CI: 1.44–1.80; p < 0.001) respectively. Therefore, systematic interventions to encourage physical activity and smoking cessation need to be actively considered in the early stages of CKD.

Physical Activity in the Prevention of Development and Progression of Kidney Disease in Type 1 Diabetes

PURPOSE OF REVIEW

Physical activity is a fundamental part of lifestyle management in diabetes care. Although its benefits are very well recognized in the general population and in people with type 2 diabetes, much less is known about the effects of exercise in type 1 diabetes. In particular, exercise effects in relation to diabetic kidney disease (DKD) are understudied. Some uncertainties about physical activity recommendations stem from the fact that strenuous exercise may worsen albuminuria immediately after the activity. However, in middle-aged and older adults without diabetes, observational studies have suggested that physical activity is associated with a decreased risk of rapid kidney function deterioration. In this review, we focus on the role of physical activity in patients with DKD and type 1 diabetes.

RECENT FINDINGS

Hereby, we present data that show that in individuals at risk of DKD or with established DKD, regular moderate-to-vigorous physical activity was associated with reduced incidence and progression of DKD, as well as reduced risk of cardiovascular events and mortality. Therefore, regular moderate-to-vigorous exercise should become a central part of the management of individuals with type 1 diabetes, in the absence of contraindications and accompanied with all needed educational support for optimal diabetes management.

Validation of a New Physical Activity Instrument Against Pedometers Among Dialysis Patients

OBJECTIVE(S)

The newly developed Low Physical Activity Questionnaire (LoPAQ) was designed to capture the low activity level among typically sedentary patients undergoing dialysis and correlated well with a physical activity questionnaire used in the general population. However, this instrument has not been validated against a more objective measure.

METHODS

We recruited patients receiving dialysis for ≥3 months from 3 dialysis facilities in San Francisco. Spontaneous walking activity was measured by pedometers over 7 days including a weekend and used as the standard reference. Patients were instructed to record their activities and step count readings. Study coordinators administered the LoPAQ during a dialysis session (hemodialysis [HD]) or clinic visit (peritoneal dialysis [PD]). The LoPAQ ascertains time and energy expended in walking activity, as well as light, moderate, and vigorous activity, and total physical activity during a 1-week recall period with 11 simple questions and requires approximately 10 minutes to administer. The LoPAQ also asks about time spent in sitting activities over 1 week. Spearman correlation was used to determine whether the LoPAQ results correlate with step counts.

RESULTS

Sixty dialysis patients (HD = 48, PD = 12) completed the LoPAQ and wore a pedometer for 1 week. Mean age was 58.0 ± 12.7 years, 78.3% were men, and median dialysis vintage was 3.1 (IQR, 1.1-5.8) years. Median step count was 2,630.5 (1,270.7-5,137) steps/day. Most patients (82.8%) reported walking activity around the neighborhood, for transportation, and/or for fitness or pleasure, with a median of 595 (70-1,566.3) kcal/week. Total kilocalories per week of physical activity reported on the LoPAQ were 655 (422.8-2,336.8). Participants reported an average of 5 (3-8) sedentary hours per day. Energy expenditure in walking by the LoPAQ was highly correlated with weekly step counts (rho = 0.53, P < .001). In addition, the overall activity reported on the LoPAQ correlated with weekly pedometer readings (rho = 0.35, P = .01) and did not differ between HD and PD patients.

CONCLUSIONS

The LoPAQ was easier and less time-consuming than previously validated physical activity questionnaires. LoPAQ demonstrated a good correlation with objective pedometer step counts among dialysis patients, similar to other physical activity instruments used in healthier and more active populations.