Physical functioning in end-stage renal disease patients: update 2005

Physical functioning in patients with end-stage renal disease treated with dialysis is low, whether measured using objective laboratory measures, physical performance testing, or self-reported measures. Peak oxygen uptake (VO2peak), self-reported functioning measures, and physical activity levels are independent predictors of mortality in these patients. Cardiovascular exercise training studies result in improvements in VO2peak, physical performance tests, and self-reported functioning. Resistance exercise training improves muscle strength. Exercise training may have positive benefits on other factors that are important clinical issues in dialysis patients, including cardiovascular risk profile, oxidative stress, and inflammation. Endothelial function, a surrogate marker of atherosclerosis, has been shown to improve with exercise training in dialysis patients. Although there have been numerous recent studies on benefits of exercise, few dialysis clinics or nephrologists provide encouragement or programs as a part of their routine care of their patients. There are many national guidelines that include exercise or increasing physical activity as a part of the treatment of many conditions that are relevant in dialysis patients, including hypertension, hyperlipidemia, and high cardiovascular disease risk. The nephrology community continues to state concern for outcomes; however, a simple, low-tech intervention that has many benefits to their patients (i.e., encouragement, recommendations, and opportunity for increasing physical activity) has not been adopted as part of the standard care. Adoption of routine counseling and encouragement for physical activity has the potential to improve outcomes, improve physical functioning, and optimize quality of life and overall health of dialysis patients.     

The effect of intradialytic exercise twice a week on the physical capacity,inflammation, and nutritional status of dialysis patients: A randomized controlled trial

Introduction: Inactivity, uremia, and malnutrition in dialysis patients may lead to decreased muscle mass and physical capacity. As a preventative measure, dialysis patients are provided with an intradialytic exercise program. Our study aimed to determine the role of intradialytic exercise performed 2 times per week on physical capacity, inflammation, and nutritional status in dialysis patients and to determine which exercises are more suitable for this population. Methods: A randomized clinical trial in which participants were randomly assigned to 1 of 3 groups, i.e., a group of patients performing aerobic exercise, a group of patients performing a combination of aerobic and resistance exercise and the control group. The study was conducted at the Dialysis Unit of Dr. Cipto Mangunkusumo General Hospital, Jakarta for 12 weeks from February to May 2018. The inclusion criteria were dialysis patients aged over 18 years who had undergone routine dialysis for over 3 months. Findings: A total of one hundred twenty patients were included in the study. There was a significant increase in lower extremity strength in the group performing aerobic exercise and in the combined exercise group compared to the lower extremity strength of the control group. There was also a significant increase in the physical component score (PCS) of the KDQOL‐SF? instrument in the aerobic training and combination exercise groups compared to the PCS of the control group. No significant differences were found between the combination exercise group and the aerobic training group in any outcome. Discussion: Both types of exercise programs significantly increased the lower extremity muscle strength and the PCS of the quality of life index. Combination exercise was not more effective than aerobic exercise for dialysis patients.     

Correlates of ADL difficulty in a large hemodialysis cohort

Needing assistance with activities of daily living (ADL) is an early indicator of functional decline and has important implications for individuals' quality of life. However, correlates of need for ADL assistance have received limited attention among patients undergoing maintenance hemodialysis (HD). A multicenter cohort of 742 prevalent HD patients was assessed in 2009–2011 and classified as frail, prefrail and nonfrail by the Fried frailty index (recent unintentional weight loss, reported exhaustion, low grip strength, slow walk speed, low physical activity). Patients reported need for assistance with 4 ADL tasks and identified contributing symptoms/conditions (pain, balance, endurance, weakness, others). Nearly 1 in 5 patients needed assistance with 1 or more ADL. Multivariable analysis showed increased odds for needing ADL assistance among frail (odds ratio [OR] 11.35; 95% confidence interval [CI] 5.50–23.41; P < 0.001) and prefrail (OR 1.93; 95% CI 1.01–3.68; P = 0.046) compared with non‐frail patients. In addition, the odds for needing ADL assistance were lower among blacks compared with whites and were higher among patients with diabetes, lung disease, and stroke. Balance, weakness, and “other” (frequently dialysis‐related) symptoms/conditions were the most frequently named reasons for ADL difficulty. In addition to interventions such as increasing physical activity that might delay or reverse the process of frailty, the immediate symptoms/conditions to which individuals attribute their ADL difficulty may have clinical relevance for developing targeted management and/or treatment approaches.     

Vitamin D and skeletal muscle: A narrative review focusing on chronic kidney disease and dialysis

Morphological, molecular, and physiological effects of vitamin D on skeletal muscle have been analyzed both in animals and humans. Vitamin D may be a potential therapeutic for increasing muscle mass and function. The presence of vitamin D receptors in skeletal muscle cells is already established. However, there is still need for more evidence about the effect of vitamin D on muscle. Some studies have associated vitamin D and skeletal muscle in chronic kidney disease (CKD) patients; most of these studies enrolled hemodialysis patients. FGF-23 and Klotho were recently described in mineral and bone disorders in CKD, resulting in reductions in calcitriol levels. Therefore, both Klotho and FGF-23 may play a role in muscle loss in CKD, which is related to morbidity and mortality risk. Therefore, this article presents a narrative review, aiming to discuss the available information associating skeletal muscle and vitamin D, highlighting the results in CKD and dialysis patients.     

Physical disability, psychological status, and health-related quality of life in older hemodialysis patients and age-matched controls

We aimed at comparing the elderly adults and normal subjects with regard to their disability, psychological status, and quality of life (QOL). One hundred and twenty-five dialysis patients and 61 controls were recruited in the study. Depression and anxiety symptoms of the patients were evaluated with the Psychological Symptom Screening List (SCL 90-R). For evaluating the disability, the Rivermead mobility index (RMI) was utilized. For evaluating the QOL, we used the short form-36 (SF-36) scale. The Rivermead mobility index of the patients (9.6 +/- 3.4) was found. When compared with controls, dialysis patients had higher levels of disability (p = 0.0001). Depression and anxiety symptom scores of these patients were also significantly higher than that of the controls (p < 0.05). There was a correlation between the disability and depression symptom scores (r: 0.171, p = 0.037). Both physical and mental capacity scores of the dialysis patients were lower than those of the controls (p < 0.05 and p < 0.05) QOL scores for elderly hemodialysis patients were found to be lower. Their disability was higher, making them dependable on others during their daily lives. Specific exercise programs should be developed for these patients. Even the smallest effort in this regard will result in improvements in physical functioning while bringing them significant benefits.     

Association between depression and inflammatory/anti‐inflammatory cytokines in chronic kidney disease and end‐stage renal disease patients: A review of literature

Depression is a common psychiatric disorder in patients with advanced chronic kidney diseases (CKDs). Strong correlation has been reported between depression and patients' morbidity and mortality among dialysis patients. On the contrary, chronic inflammation may be a major contributor to morbidity and mortality in these patients. Elevated plasma levels of proinflammatory cytokines, especially C‐reactive protein and interleukin (IL)‐6, have been correlated with cardiovascular events, hospitalization, and all‐cause and cardiovascular‐associated mortality in dialysis patients. Studies suggested that inflammation‐mediated atherosclerotic cardiovascular diseases are the possible reasons for depression‐induced mortality among patients without renal diseases. Several studies found significant elevations in circulating levels of proinflammatory cytokines, particularly IL‐6 and tumor necrosis factor‐α, in patients with major depression. Furthermore, depressive mood and behaviors, including sadness and suicidal ideation, were observed in patients who received repeated injections of recombinant cytokines. A thorough literature review indicates that while depressive symptoms and elevated inflammatory cytokine levels coexist in CKD and dialysis patients, their association is uncertain. Depression seems to be more associated with elevated serum levels of IL‐6 than other cytokines in these patients. Further studies are needed to clarify the possibility of a causal relationship between inflammation and depressive symptoms in CKD and dialysis patients.     

Dialysate calcium and calcium/phosphate balance in hemodialysis

The changing pattern of pharmaceutical use in dialysis patients has resulted in several alterations to dialysate calcium concentration over the past 40 years. Non‐calcium–containing phosphate binders and calcimimetics are the most recent examples of drugs that influence the overall calcium balance in dialysis patients. Renal osteodystrophy, vascular disease, and mortality are believed to be linked in patients with chronic kidney disease (CKD), although to date most of the evidence is based only on statistical associations. The precise pathophysiology of vascular calcification in end‐stage renal disease is unknown, but risk factors include age, hypertension, time on dialysis, and, most significantly, abnormalities in calcium and phosphate balance. Prospective studies are required before “cause and effect” can be established with certainty, but it is an active metabolic process with inhibitors and promoters. Serum calcium levels are clearly influenced by dialysate calcium and may therefore play an important role in influencing vascular calcification. Clinical management of hyperphosphatemia is being made easier by the introduction of potent non‐calcium–based oral phosphate binders such as lanthanum carbonate. Short‐term and long‐term studies have demonstrated its efficacy and safety. Vitamin D analogs have been a disappointment in the control of serum parathyroid hormone (PTH) levels, but evidence is emerging that vitamin D has other important metabolic effects apart from this, and may confer survival advantages to patients with CKD. Calcimimetics such as cinacalcet enable much more effective and precise control of PTH levels, but at the cost of a major financial burden. While it is unreasonable to expect that any one of these recent pharmacological developments will be a panacea, they provide researchers with the tools to begin to examine the complex interplay between calcium, phosphate, vitamin D, and PTH, such that further progress is fortunately inevitable.     

Protecting the endothelium: a new focus for management of chronic kidney disease

It is being increasingly recognized that cardiovascular disease (CVD) and its complications are the most important cause of morbidity and mortality in patients with chronic kidney disease (CKD) and dialysis patients. If outcomes for these patients are to be improved, therapeutic strategies at all stages of CKD will have to target the etiologies and mechanisms that lead to CVD. In this review, we focus on the central role of endothelial dysfunction as the critical precursor of CVD. We argue that a better understanding of endothelial dysfunction by nephrologists and dialysis physicians is necessary if there is to be success in limiting the CVD epidemic that kills and maims our patients. The extensive studies to explain the high prevalence of vascular disease in patients with CKD have shown the close relationship among endothelial dysfunction, inflammation, and atherosclerosis. The pathogenesis starts with endothelial cell injury from any of many possible causes, and strategies to reduce the burden of CVD in uremic and dialysis patients must be directed at restoring normal endothelial function or, at the least, preventing aggravation of endothelial damage. At the center of the exploration of endothelial dysfunction and atherosclerosis are oxidative stress and inflammation. Of these, which is the chicken and which is the egg is unknown, but in the setting of uremia, endothelial injury because of free radical, oxidative stress is likely to precede inflammation. The issues raised here are highly complex and most renal practitioners may not have been adequately exposed to the background research underlying current thinking of the pathogenesis of vascular disease. Clearly, progress in management of CVD in patients with CKD will require collaboration with experts in the research and treatment of vascular disease. Nephrologists seeking optimum outcomes for patients with CKD will need to become "endotheliologists" or, at the least, subscribe to a mission "to protect the endothelium."     

Management of coronary artery disease and acute coronary syndrome in the chronic kidney disease population—A review of the current literature

Coronary Artery Disease (CAD) is a large contributor to morbidity and mortality in the chronic kidney disease (CKD) and end‐stage renal disease (ESRD) population. Due to the fact that many large‐scale trials evaluating management for acute coronary syndromes (ACS) and CAD have excluded patients with CKD, there is a paucity of data investigating medical management of CAD and revascularization strategies of these patients. Further, while there have been many advances in the treatment for ACS and CAD, both medically and technologically, few studies have focused on the CKD population and many predate these advancements in management. Newer studies that include CKD patients have shown heterogeneity in various outcomes, making management decisions challenging. In this review, we summarize the epidemiologic significance of ACS and CAD in patients with CKD, discuss the diagnosis of ACS in this patient population, and review the therapeutic interventions in patients with CKD.     

A closer look at frailty in ESRD: Getting the measure right

Patients treated with dialysis have low levels of physical functioning and activity. Whether this translates into frailty or not may depend on how the frailty phenotype is operationalized. This is a secondary analysis of data from the Renal Exercise Demonstration Project to evaluate two methods of operationalizing the Fried phenotype for frailty: Using measured walking speed and muscle weakness (FRAILmeas) and using substitution of the Physical Function Scale (PF) from the SF‐36 questionnaire for walking speed and muscle weakness (FRAILsubst). Complete data for both measures were available for 188 hemodialysis patients. The frailty score (FRAILmeas) was the sum of criteria scores for measured gait speed, chair stand, body mass index, vitality, and physical activity. The frailty score (FRAILsubst) substituted the PF scale score (<75) as a surrogate measure for gait speed and for weakness. The frailty score ranged from 0 to 5. Scores ≥3 were categorized as frail, and <3 as not frail. The substitution of the PF score for walking speed and muscle weakness resulted in 78% of patients being categorized as frail compared to 24% using actual measured walking speed and muscle weakness (P < .001). The component of frailty that had the highest prevalence was low physical activity (average 54% of subjects). Frailty (using the FRAILmeas) was higher in patients with increasing age, female gender, and lower self‐reported PF. Frailty is highly prevalent in hemodialysis patients; however, measured constructs of the components of frailty should be used to report the frailty phenotype.     

Indoxyl sulfate,a valuable biomarker in chronic kidney disease and dialysis

Chronic kidney disease (CKD) is an increasingly recognized disease with high global incidence and mortality. Yet, the existing diagnostic tools are not sufficient enough to predict prognosis of CKD and CKD comorbidities. Indoxyl sulfate, a typical uremic toxin, is of great importance in the development of CKD with its nephrotoxicity, cardiovascular toxicity, and bone toxicity. Some reports suggest that indoxyl sulfate directly associate with renal function loss and mortality in CKD patients. This review discusses the diagnostic value of indoxyl sulfate from its biological characteristics, pathophysiological effects, related therapies, and its diagnostic value in clinical studies.     

Fallacies of High‐Speed Hemodialysis

Chronic hemodialysis sessions, as developed in Seattle in the 1960s, were long procedures with minimal intra‐ and interdialytic symptoms. Financial and logistical pressures related to the overwhelming number of patients requiring hemodialysis created an incentive to shorten dialysis time to four, three, and even two hours per session in a thrice weekly schedule. This method spread rapidly, particularly in the United States, after the National Cooperative Dialysis Study suggested that time of dialysis is of minor importance as long as urea clearance multiplied by dialysis time and scaled to total body water (Kt/V_urea) equals 0.95–1.0. This number was later increased to 1.3, but the assumption remained unchanged that hemodialysis time is of minimal importance as long as it is compensated by increased urea clearance. Patients accepted short dialysis as a godsend, believing that it would not be detrimental to their well‐being and longevity. However, Kt/V_urea measures only removal of low molecular weight substances and does not consider removal of larger molecules. Besides, it does not correlate with the other important function of hemodialysis, namely ultrafiltration. Whereas patients with substantial residual renal function may tolerate short dialysis sessions, the patients with little or no urine output tolerate short dialyses poorly because the ultrafiltration rate at the same interdialytic weight gain is inversely proportional to dialysis time. Rapid ultrafiltration is associated with cramps, nausea, vomiting, headache, fatigue, hypotensive episodes during dialysis, and hangover after dialysis; patients remain fluid overloaded with subsequent poor blood pressure control, left ventricular hypertrophy, diastolic dysfunction, and high cardiovascular mortality. Short, high‐efficiency dialysis requires high blood flow, which increases demands on blood access. The classic wrist arteriovenous fistula, the access with the best longevity and lowest complication rates, provides “insufficient” blood flow and is replaced with an arteriovenous graft fistula or an intravenous catheter. Moreover, to achieve high blood flows, large diameter intravenous catheters are used; these fit veins “too tightly,” so predispose the patient to central‐vein thrombosis. Longer hemodialysis sessions (5–8 hrs, thrice weekly), as practiced in some centers, are associated with lower complication rates and better outcomes. Frequent dialyses (four or more sessions per week) provide better clinical results, but are associated with increased cost. It is my strong belief that a wide acceptance of longer, gentler dialysis sessions, even in a thrice weekly schedule, would improve overall hemodialysis results and decrease access complications, hospitalizations, and mortality, particularly in anuric patients.     

Dialysis patients treated with Epoetin α show improved exercise tolerance and physical function: A new analysis of the Canadian Erythropoietin Study Group trial

The risks/benefits of anemia treatment in dialysis patients have been redefined in the US Epoetin α label. This analysis was carried out to determine if increasing hemoglobin (Hb) levels improve exercise tolerance and physical function in anemic dialysis patients. This is a new analysis of the Canadian Erythropoietin Study Group trial, a double‐blind, randomized, placebo‐controlled trial in dialysis patients. Subjects were 18 to 75 years old, on hemodialysis for >3 months, and had a baseline Hb <9.0 g/dL. Patients with a history of diabetes mellitus, ischemic heart disease, or severe/uncontrolled hypertension were excluded. Patients were randomized to receive Epoetin α to a target Hb of 9.5 to 11.0 g/dL (n=40) or a target of 11.5 to 13.0 g/dL (n=38), or receive placebo (n=40). Results from patients in the Epoetin‐α–treated arms were combined for this analysis. Hb level, exercise tolerance (Treadmill Stress Test and 6‐Minute Walk Test) and patient‐reported physical function measures (Physical Summary domain from the Kidney Disease Questionnaire, and 4 domains from the Sickness Impact Profile) were reported at baseline and months 2, 4, and 6. Differences in measures were statistically significant for exercise tolerance (Treadmill Stress, P=0.0001) and patient‐reported physical function (Kidney Disease Questionnaire Physical, P=0.0001; Sickness Impact Profile Physical, P=0.0015) across all time points for Epoetin‐α–treated patients compared with placebo. Improvements were seen at 2 months and were maintained through months 4 and 6. Dialysis patients receiving Epoetin α showed improved exercise tolerance and physical function. These findings should be considered as physicians weigh the risks and benefits of treatment.     

Self‐perceived quality of sleep and mortality in Norwegian dialysis patients

Sleep complaints are prevalent and associated with poor health‐related quality of life (HRQoL), depression and possibly mortality in dialysis patients. This study aimed to explore possible associations between sleep quality, daytime sleepiness and mortality in dialysis patients. In this study, 301 dialysis patients were followed up to 4.3 years. HRQoL was evaluated at baseline with the Kidney Disease and Quality of Life—Short Form (KDQoL‐SF), depression with Beck Depression Inventory (BDI), sleep quality with Pittsburgh Sleep Quality Index and daytime sleepiness with Epworth Sleepiness Scale. The single item “on a scale from 0–10, how would you evaluate your sleep?” in the sleep subscale in KDQoL‐SF was used to identify poor (0–5) and good sleepers (6–10). A total of 160 patients (53.3%) were characterized as poor sleepers. They were younger (r = 0.241, P < 0.001), had more depression (BDI: 8.72 ± 6.79 vs. 13.60 ± 8.04, P < 0.001), a higher consumption of hypnotics and antidepressants and reduced HRQoL (Mental Component Summary score: 45.4 ± 11.0 vs. 50.0 ± 10.4, P < 0.001. Physical Component Summary score: 35.0 ± 9.9 vs. 38.5 ± 10.5, P = 0.004). In multivariate analyses, poor sleepers had nearly a twofold increase in mortality risk (hazard ratio [HR] 1.92, confidence interval [CI] 1.10‐3.35, P = 0.022). Daytime sleepiness was not related to mortality (HR 1.01, CI 0.95‐1.08, P = 0.751). Sleep complaints predicted increased mortality risk in dialysis patients and should therefore be routinely assessed. Further studies are needed to find suitable treatment options for poor sleep in dialysis patients as it may affect both HRQoL and survival.     

Costs of managing anemia with erythropoiesis‐stimulating agents during hemodialysis: A time and motion study

Use of erythropoiesis‐stimulating agents (ESAs) presents a significant time and cost burden in the management of anemia of chronic kidney disease (CKD). We conducted a prospective, observational, activity‐based costing study to estimate the health care personnel time and resulting direct medical costs associated with administering epoetin 3 times weekly to patients with end‐stage renal disease on dialysis. The study was conducted at 5 US hemodialysis centers. The personnel time and costs were derived from time and motion observations. Predicted time and cost savings were modeled for switching patients to once‐monthly ESA therapy. Patients also completed a survey questionnaire to assess their level of CKD knowledge and information needs. Total per‐patient‐per‐year (PPPY) time expended on anemia management with epoetin averaged 608 minutes (range 512–915 minutes), with an average PPPY cost of $548 (range $342–$651). Use of a once‐monthly ESA, compared with epoetin, could decrease average PPPY time expenditure by 79% (127 minutes [range 96–173 minutes]) and reduce PPPY costs by 81% ($104 [range $79–$136]). The patient questionnaire reported insufficient education on CKD. Use of a once‐monthly ESA to correct anemia in dialysis patients may provide substantial time, resource, and cost savings compared with current treatment practices.     

Personal viewpoint: hemodialysis--water, power, and waste disposal: rethinking our environmental responsibilities

While medical health professionals are trained to detect, treat, and comfort, they are not trained to consider the environmental impact of the services they provide. Dialysis practitioners seem particularly careless in the use of natural resources—especially water and power—and seem broadly ignorant of the profound medical waste issues created by single use dialysis equipment. If the data we have collected is an indication, then extrapolation of this data to a dialysis population currently estimated at ~2 million patients worldwide, a “world dialysis service” would use ~156 billion liters of water and discard ~2/3 of that during reverse osmosis. This waste occurs, despite the discarded water being high-grade “gray water” of potable standard. The same world dialysis service would consume 1.62 billion kWh of power—mostly generated from coal and other environmentally damaging sources. Our world dialysis service, based on ~2 kg of waste from each dialysis treatment, would generate ~625,000 tonnes of plastic waste—waste that would be potentially reusable if simple sterilizing techniques were applied to it at the point of generation. Dialysis services must begin to explore eco-dialysis potentials. The continued plundering of resources without considering reuse or recycling, exploration of renewable energy options, or the reduction of the carbon footprint of the dialysis process . . . is unsustainable. Sustainable dialysis practices should be a global goal in the coming decade.     

Barriers,biases, and beliefs about arteriovenous fistula placement in children: A survey of the International Pediatric Fistula First Initiative (IPFFI) within the Midwest Pediatric Nephrology Consortium (MWPNC)

There has been recent emphasis on increased arteriovenous fistula (AVF) use and decreased central venous catheter use in hemodialysis (HD) patients. The International Pediatric Fistula First Initiative was founded via collaborative effort with the Midwest Pediatric Nephrology Consortium to alert nephrologists, surgeons, and dialysis staff to consider fistulae as the best access in pediatric HD patients. A multidisciplinary educational DVD outlining expectations and strategies to increase AVF placement and usage in children was created. Participants were administered a survey previewing and postviewing to identify barriers to placement and usage of AVF in children. A total of 52 surveys were subdivided as either “dialysis staff” or “proceduralist” at five centers. Thirty‐three percent of respondents were unaware if their practice was following published guidelines. Sixty‐five percent of respondents stated they referred to a dedicated vascular access surgeon at their respective institutions. Methods used to monitor AVF function included physical exam, venous pressure monitoring, and ultrasound dilution. Vascular access was placed within 3 months in only 35% of patients. Interdisciplinary communication problems between surgeons, interventional radiologists, and nephrologists were identified as a major barrier. Lack of AVF usage was often due to maturation failure. Routine access rounds did not occur in any centers. Regarding monitoring, 74% of the respondents use physical exam, 26% use venous pressure monitoring, and 9% use ultrasound dilution. Ninety‐three percent of dialysis staff stated they would change practice patterns following the intervention; however, 12% of surgeons stated they would alter practice patterns. To our knowledge, this is the first report to identify barriers to placement of AVF in children from the perspectives of multidisciplinary team members including pediatric nephrologists, surgeons, interventional radiologists, and multidisciplinary dialysis staff.     

Physician knowledge,attitudes, and practices regarding physical activity restrictions in pediatric hemodialysis patients

Introduction

Epidemiologic studies of physical activity among pediatric hemodialysis (HD) patients are lacking. A sedentary lifestyle in End-Stage Kidney Disease is associated with a higher cardiovascular mortality risk. In those patients receiving HD, time spent on dialysis and restrictions on physical activity due to access also contribute. No consensus exists regarding physical activity restrictions based on vascular access type. The aim of this study was to describe the patterns of physical activity restrictions imposed by pediatric nephrologists on pediatric HD patients and to understand the basis for these restrictions.

Methods

We conducted a cross-sectional study involving US pediatric nephrologists using an anonymized survey through Pediatric Nephrology Research Consortium. The survey consisted of 19 items, 6 questions detailed physician characteristics with the subsequent 13 addressing physical activity restrictions.

Findings

A total of 35 responses (35% response rate) were received. The average years in practice after fellowship was 11.5 years. Significant restrictions were placed on physical activity and water exposure. None of the participants reported accesses damage or loss that was attributed to physical activity and sport participation. Physicians practice is based on their personal experience, standard practice at their HD center, and clinical practices they were taught.

Discussion

There is no consensus among pediatric nephrologists about allowable physical activity in children receiving HD. Due to the lack of objective data, individual physician beliefs have been utilized to restrict activities in the absence of any deleterious effects to accesses. This survey clearly demonstrates the need for more prospective and detailed studies to develop guidelines regarding physical activity and dialysis access in order to optimize quality of care in these children.     

Calcium‐phosphate and parathyroid intradialytic profiles: A potential aid for tailoring the dialysate calcium content of patients on different hemodialysis schedules

Severe hyperparathyroidism is a challenge on hemodialysis. The definition of dialysate calcium (Ca) is a pending issue with renewed importance in cases of individualized dialysis schedules and of portable home dialysis machines with low‐flow dialysate. Direct measurement of calcium mass transfer is complex and is imprecisely reflected by differences in start‐to‐end of dialysis Ca levels. The study was performed in a dialysis unit dedicated to home hemodialysis and to critical patients with wide use of daily and tailored schedules. The Ca‐phosphate (P)‐parathyroid hormone (PTH) profile includes creatinine, urea, total and ionized Ca, albumin, sodium, potassium, P, PTH levels at start, mid, and end of dialysis. “Severe” secondary hyperparathyroidism was defined as PTH > 300 pg/mL for ≥3 months. Four schedules were tested: conventional dialysis (polysulfone dialyzer 1.8–2.1 m²), with dialysate Ca 1.5 or 1.75 mmol/L, NxStage (Ca 1.5 mmol/L), and NxStage plus intradialytic Ca infusion. Dosages of vitamin D, calcium, phosphate binders, and Ca mimetic agents were adjusted monthly. Eighty Ca‐P‐PTH profiles were collected in 12 patients. Serum phosphate was efficiently reduced by all techniques. No differences in start‐to‐end PTH and Ca levels on dialysis were observed in patients with PTH levels < 300 pg/mL. Conversely, Ca levels in “severe” secondary hyperparathyroid patients significantly increased and PTH decreased during dialysis on all schedules except on Nxstage (P < 0.05). Our data support the need for tailored dialysate Ca content, even on “low‐flow” daily home dialysis, in “severe” secondary hyperparathyroid patients in order to increase the therapeutic potentials of the new dialysis techniques.