Vitamin D deficiency (<20 ng/mL) and insufficiency (20-29 ng/mL) are common among patients with chronic kidney disease (CKD) or undergoing dialysis. In addition to nutritional and sunlight exposure ...deficits, factors that affect vitamin D deficiency include race, sex, age, obesity and impaired vitamin D synthesis and metabolism. Serum 1,25(OH)₂D levels also decrease progressively because of 25(OH)D deficiency, together with impaired availability of 25(OH)D by renal proximal tubular cells, high fibroblast growth factor (FGF)-23 and decreased functional renal tissue. As in the general population, this condition is associated with increased morbidity and poor outcomes. Together with the progressive decline of serum calcitriol, vitamin D deficiency leads to secondary hyperparathyroidism (SHPT) and its complications, tertiary hyperparathyroidism and hypercalcemia, which require surgical parathyroidectomy or calcimimetics. Kidney Disease Outcomes Quality Initiative (KDOQI) and Kidney Disease Improving Global Outcomes (KDIGO) experts have recognized that vitamin D insufficiency and deficiency should be avoided in CKD and dialysis patients by using supplementation to prevent SHPT. Many vitamin D supplementation regimens using either ergocalciferol or cholecalciferol daily, weekly or monthly have been reported. The benefit of native vitamin D supplementation remains debatable because observational studies suggest that vitamin D receptor activator (VDRA) use is associated with better outcomes and it is more efficient for decreasing the serum parathormone (PTH) levels. Vitamin D has pleiotropic effects on the immune, cardiovascular and neurological systems and on antineoplastic activity. Extra-renal organs possess the enzymatic capacity to convert 25(OH)D to 1,25(OH)₂D. Despite many unanswered questions, much data support vitamin D use in renal patients. This article emphasizes the role of native vitamin D replacement during all-phases of CKD together with VDRA when SHPT persists.
Chronic Fluid Overload and Mortality in ESRD Zoccali, Carmine; Moissl, Ulrich; Chazot, Charles ...
Journal of the American Society of Nephrology,
08/2017, Letnik:
28, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Sustained fluid overload (FO) is considered a major cause of hypertension, heart failure, and mortality in patients with ESRD on maintenance hemodialysis. However, there has not been a cohort study ...investigating the relationship between chronic exposure to FO and mortality in this population. We studied the relationship of baseline and cumulative FO exposure over 1 year with mortality in 39,566 patients with incident ESRD in a large dialysis network in 26 countries using whole-body bioimpedance spectroscopy to assess fluid status. Analyses were applied across three discrete systolic BP (syst-BP) categories (<130, 130-160, and >160 mmHg), with nonoverhydrated patients with syst-BP=130-160 mmHg as the reference category; >200,000 FO measurements were performed over follow-up. Baseline FO value predicted excess risk of mortality across syst-BP categories (<130 mmHg: hazard ratio HR, 1.51; 95% confidence interval 95% CI, 1.38 to 1.65; 130-160 mmHg: HR, 1.25; 95% CI, 1.16 to 1.36; >160 mmHg: HR, 1.30; 95% CI, 1.19 to 1.42; all
<0.001). However, cumulative 1-year FO exposure predicted a higher death risk (
<0.001) across all syst-BP categories (<130 mmHg: HR, 1.94; 95% CI, 1.68 to 2.23; 130-160 mmHg: HR, 1.51; 95% CI, 1.35 to 1.69; >160 mmHg: HR, 1.62; 95% CI, 1.39 to 1.90). In conclusion, chronic exposure to FO in ESRD is a strong risk factor for death across discrete BP categories. Whether treatment policies that account for fluid status monitoring are preferable to policies that account solely for predialysis BP measurements remains to be tested in a clinical trial.
Abstract
Introduction
Sustainable growth and environmental issues are currently a topic for all human activities, and dialysis represents a real challenge in this field because of high water and ...power consumption and the production of large amounts of care-related waste. In this article we describe data collection implemented in the NephroCare centres in France and the changes observed during a 13-year period regarding environmental parameters.
Methods
Monthly data collection (eco-reporting) was implemented in NephroCare centres in France in 2005. It covers three topics designed as key performance indicators (KPIs): electricity and water consumption and care-related waste production expressed, respectively, as kilowatt-hour (kWh), litres (L) and kilograms per session. We report on the three action plans (2005–10, 2011–14 and 2015–18) and changes observed during this 13-year period.
Results
During the period, power and water consumption declined by 29.6% (from 23.1 to 16.26 kWh/session) and 52% (from 801 to 382 L/session), respectively. At the same time, the yearly number of dialysis sessions has increased from 169 335 to 399 336. The sources of savings came both from improvements in the dialysis technology (dialysis machines and water treatment systems) and from updating and remodelling of the dialysis unit equipment and buildings. The care-related waste decreased from 1.8 to 1.1 kg because of regular staff training and the retrofiltration system, allowing the voiding of the remaining saline solution after dialysis. These savings have been estimated as equivalent to 102 440 tons of carbon dioxide.
Discussion
Implementation of KPIs and their regular monitoring by trained staff to evaluate water and power consumption and the reduction of care-related water production are essential to implement actions to reduce the impact of dialysis on the environment. These data show the importance of water treatment and dialysis technology to decrease water and power consumption and the production of care-related waste as well as upgrading or remodelling of buildings housing dialysis units. Other measures are discussed, including the reuse of rejected water by reverse osmosis, as well as behavioural changes that are needed to reach sustainable development of dialysis.
Conclusion
The first step to reach ‘green’ dialysis is to collect precise information from defined KPIs. This is the only way to design action plans to reduce the impact of dialysis therapy on the environment. Beyond this, the nephrology community must be sensitized to this challenge to be proactive and to anticipate future regulations.
Fluid volume and hemodynamic management in hemodialysis patients is an essential component of dialysis adequacy. Restoring salt and water homeostasis in hemodialysis patients has been a permanent ...quest by nephrologists summarized by the 'dry weight' probing approach. Although this clinical approach has been associated with benefits on cardiovascular outcome, it is now challenged by recent studies showing that intensity or aggressiveness to remove fluid during intermittent dialysis is associated with cardiovascular stress and potential organ damage. A more precise approach is required to improve cardiovascular outcome in this high-risk population. Fluid status assessment and monitoring rely on four components: clinical assessment, non-invasive instrumental tools (e.g., US, bioimpedance, blood volume monitoring), cardiac biomarkers (e.g. natriuretic peptides), and algorithm and sodium modeling to estimate mass transfer. Optimal management of fluid and sodium imbalance in dialysis patients consist in adjusting salt and fluid removal by dialysis (ultrafiltration, dialysate sodium) and by restricting salt intake and fluid gain between dialysis sessions. Modern technology using biosensors and feedback control tools embarked on dialysis machine, with sophisticated analytics will provide direct handling of sodium and water in a more precise and personalized way. It is envisaged in the near future that these tools will support physician decision making with high potential of improving cardiovascular outcome.
Summary Extracellular volume overload and hypertension are important contributors to the high risk of cardiovascular mortality in patients undergoing haemodialysis. Hypertension is present in more ...than 90% of patients at the initiation of haemodialysis and persists in more than two-thirds, despite use of several antihypertensive medications. High blood pressure is a risk factor for the development of left ventricular hypertrophy, heart failure, and mortality, although there are controversies with some study findings showing poor survival with low—but not high—blood pressure. The most frequent cause of hypertension in patients undergoing haemodialysis is volume overload, which is associated with poor cardiovascular outcomes itself independent of blood pressure. Although antihypertensive medications might not be successful to control blood pressure, extracellular volume reduction by persistent ultrafiltration and dietary salt restriction can produce favourable results with good blood pressure control. More frequent or longer haemodialysis can facilitate volume and blood pressure control. However, successful volume and blood pressure control is also possible in patients undergoing conventional haemodialysis.
Environment has become a main issue of human activities. Chronic hemodialysis (HD) therapy saves lives but consumes large amounts of water and power and produces a lot of care‐related waste. On‐line ...hemodiafiltration (HDF) improves patients' outcomes but increases water consumption from ultra‐pure water needs and infusion volume. New‐generation water treatment systems have much reduced the proportion of reject water that can also be reused. Reducing the dialysate flow in standard HD decreases significantly the water consumption but impacts negatively dialysis efficiency. When on‐line HDF is prescribed, reducing the dialysate flow may be applied to decrease water needs while maintaining dialysis efficiency. Nowadays, dialysis prescription cannot ignore its impact on natural resources and environment.
Hyporesponsiveness to erythropoiesis-stimulating agent therapy in dialysis patients is poorly understood. Some studies report an improvement in the erythropoiesis-stimulating agent resistance index ...(ERI) with hemodiafiltration (HDF) versus high-flux hemodialysis (HD). We explored ERI dynamics in 38,340 incident HDF and HD patients treated in 22 countries over a 7-year period. Groups were matched by propensity score at baseline (6 months after dialysis initiation). The follow-up period (mean of 1.31 years) was stratified into 1 month intervals with delta analyses performed for key ERI-related parameters. Dialysis modality, time interval, and polycystic kidney disease were included in a linear mixed model with the outcome ERI. Baseline ERI was nonsignificantly higher in HDF versus HD treatment. ERI decreased significantly faster in HDF-treated patients than in HD-treated patients, was decreased in both HD and HDF when patients were treated with intravenous darbepoetin alfa, but only in HDF when treated with intravenous recombinant human erythropoietin (rHuEPO). A clear difference between HD- and HDF-treated patients could only be found for patients with high baseline ERI and assigned to intravenous rHuEPO treatment. A significant advantage in terms of lower ERI for patients treated by HDF was found. Sensitivity analysis limited this advantage for HDF to those patients treated with intravenous rHuEPO (not darbepoetin alfa or subcutaneous rHuEPO) and to patients with a high baseline ERI. Thus, our results allow more accurate planning for future clinical trials addressing anemia management in dialysis patients.
Management of blood pressure (BP) in patients with chronic kidney disease receiving dialysis (stage 5D) provides a significant challenge for healthcare professionals. The association between BP and ...cardiovascular disease risk has been well studied in the general population; however, in dialysis patients, physiological and dialysis-related mechanisms influencing BP are complex, and the associated risk is poorly understood. In stage 5D, BP is determined by the complex interplay of fluid volume and prescription of post-dialysis target weight, sodium load, the renin–angiotensin and sympathetic nervous systems, and diverse exogenous factors, such as administration of erythropoiesis-stimulating agents, the type and timing of administration of antihypertensive drugs, and dialysate composition. Management of BP in this population requires both generally applicable plans and individualization in order to determine the BP target and the treatment regimen. This report summarizes the deliberations and recommendations of a conference sponsored by the Kidney Disease: Improving Global Outcomes (KDIGO) to address the following questions: (1) what is the optimal BP treatment target in relation to end-organ damage and outcomes in dialysis patients; (2) how should antihypertensive drugs be used in dialysis patients; and (3) what nonpharmacological therapies can be considered in achieving BP targets? The conference report will augment the KDIGO clinical practice guideline on blood pressure in chronic kidney disease stages 1–5, which is currently under development.
The progressive decline of glomerular filtration rate in chronic kidney disease patients is associated with a significant reduction in food intake. Approximately one third of chronic dialysis ...patients complain of a fair or poor appetite and this is related directly to poor patient outcomes. Appetite regulation involves the gastrointestinal tract (ghrelin as an appetite stimulant, and cholecystokinin, glucagon-like peptide-1, and neuropeptide YY as appetite inhibitors); the adipose tissue with leptin, a potent appetite inhibitor; the vagal system; and the brain, which integrates the stimuli in the hypothalamus area. Satiety relies on the melanocortin receptors with serotonin as the main neurotransmitter and is challenged with hunger peptides, namely, neuropeptide Y and agouti-related peptide. In nondialyzed chronic renal failure patients and in maintenance dialysis patients, anorexia is related mainly to the accumulation of unidentified anorexigenic compounds, inflammatory cytokines, and alterations in appetite regulation, such as amino acid imbalance, which increases the transport of free tryptophan across the blood-brain barrier. This creates a hyperserotoninergic state that is prone to low appetite. Treatment of anorexia involves counseling, starting dialysis treatments in uremic chronic kidney disease patients, increasing the dialysis dose, and possibly using appetite stimulants.
Predialysis volume overload is the sum of interdialytic weight gain (IDWG) and residual postdialysis volume overload. It results mostly from failure to achieve an adequate volume status at the end of ...the dialysis session. Recent developments in bioimpedance spectroscopy and possibly relative plasma volume monitoring permit noninvasive volume status assessment in hemodialysis patients. A large proportion of patients have previously been shown to be chronically volume overloaded predialysis (defined as >15% above 'normal' extracellular fluid volume, equivalent to >2.5 liters on average), and to exhibit a more than twofold increased mortality risk. By contrast, the magnitude of the mortality risk associated with IDWG is much smaller and only evident with very large weight gains. Here we review the available evidence on volume overload and IDWG, and question the use of IDWG as an indicator of 'nonadherence' by describing its association with postdialysis volume depletion. We also demonstrate the relationship between IDWG, volume overload and predialysis serum sodium concentration, and comment on salt intake. Discriminating between volume overload and IDWG will likely lead to a more appropriate management of fluid withdrawal during dialysis. Consensually, the present authors agree that this discrimination should be among the primary goals for dialysis caretakers today. In consequence, we recommend objective measures of volume status beyond mere evaluations of IDWG.
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