The circadian clock remains intact, but with dampened hormonal output in heart failure.

Background: Circadian (24-h) rhythms are important regulators in physiology and disease, but systemic disease may disrupt circadian rhythmicity. Heart failure (HF) is a systemic disease affecting hormonal regulation. We investigate whether HF affects the rhythmic expression of melatonin and cortisol, main endocrine products of the central clock, and cardiac-specific troponin in patients.

Effect of Intravenous Ferric Carboxymaltose on Exercise Capacity After Kidney Transplantation (EFFECT-KTx): rationale and study protocol for a double-blind, randomised, placebo-controlled trial.

Introduction: Iron deficiency (ID) is common and has been associated with an excess mortality risk in kidney transplant recipients (KTRs). In patients with chronic heart failure and ID, intravenous iron improves exercise capacity and quality of life. Whether these beneficial effects also occur in KTRs is unknown.

Iron Administration, Infection, and Anemia Management in CKD: Untangling the Effects of Intravenous Iron Therapy on Immunity and Infection Risk.

Patients with chronic kidney disease (CKD) are at increased risk for infection, attributable to immune dysfunction, increased exposure to infectious agents, loss of cutaneous barriers, comorbid conditions, and treatment-related factors (eg, hemodialysis and immunosuppressant therapy). Because iron plays a vital role in pathogen reproduction and host immunity, it is biologically plausible that intravenous iron therapy and/or iron deficiency influence infection risk in CKD. Available data from preclinical experiments, observational studies, and randomized controlled trials are summarized to explore the interplay between intravenous iron and infection risk among patients with CKD, particularly those receiving maintenance hemodialysis.

Erythropoietin, Fibroblast Growth Factor 23, and Death After Kidney Transplantation.

Elevated levels of erythropoietin (EPO) are associated with an increased risk of death in renal transplant recipients (RTRs), but the underlying mechanisms remain unclear. Emerging data suggest that EPO stimulates production of the phosphaturic hormone fibroblast growth factor 23 (FGF23), another strong risk factor for death in RTRs. We hypothesized that the hitherto unexplained association between EPO levels and adverse outcomes may be attributable to increased levels of FGF23.

Interplay of erythropoietin, fibroblast growth factor 23, and erythroferrone in patients with hereditary hemolytic anemia.

Recently, erythropoietin (EPO) was identified as regulator of fibroblast growth factor 23 (FGF23). Proteolytic cleavage of biologically active intact FGF23 (iFGF23) results in the formation of C-terminal fragments (cFGF23). An increase in cFGF23 relative to iFGF23 suppresses FGF receptor signaling by competitive inhibition.

Prognostic biomarker soluble ST2 exhibits diurnal variation in chronic heart failure patients.

Aim: Soluble suppression of tumorigenicity-2 (sST2) is a strong prognostic biomarker in heart failure. The emerging understanding of circadian biology in cardiovascular disease may lead to novel applications in prognosis and diagnosis and may provide insight into mechanistic aspects of the disease-biomarker interaction. So far, it is unknown whether sST2 exhibits a diurnal rhythm.

Administration of Intravenous Iron Formulations Induces Complement Activation .

Intravenous (IV) iron is widely used to treat anemia in chronic kidney disease patients. Previously, iron formulations were shown to induce immune activation . The current study aimed to investigate the effect of IV iron on complement activation , and whether this subsequently induces inflammation and/or oxidative stress.

Epoetin Beta and C-Terminal Fibroblast Growth Factor 23 in Patients With Chronic Heart Failure and Chronic Kidney Disease.

Background In patients with chronic heart failure and chronic kidney disease, correction of anemia with erythropoietin-stimulating agents targeting normal hemoglobin levels is associated with an increased risk of cardiovascular morbidity and mortality. Emerging data suggest a direct effect of erythropoietin on fibroblast growth factor 23 (FGF23), elevated levels of which have been associated with adverse outcomes. We investigate effects of erythropoietin-stimulating agents in patients with both chronic heart failure and chronic kidney disease focusing on FGF23.

Creatinine synthesis rate and muscle strength and self-reported physical health in dialysis patients.

Background & Aims: Urinary creatinine excretion reflecting endogenous creatinine synthesis rate (CSR) is an established measure of muscle mass in the general populations and in patients with chronic kidney disease. There is increasing data to suggest that CSR not only reflects muscle mass, but also muscle function. In dialysis patients, CSR has rarely been studied since it requires dialysate collection.

Iron deficiency, elevated erythropoietin, fibroblast growth factor 23, and mortality in the general population of the Netherlands: A cohort study.

Background: Emerging data in chronic kidney disease (CKD) patients suggest that iron deficiency and higher circulating levels of erythropoietin (EPO) stimulate the expression and concomitant cleavage of the osteocyte-derived, phosphate-regulating hormone fibroblast growth factor 23 (FGF23), a risk factor for premature mortality. To date, clinical implications of iron deficiency and high EPO levels in the general population, and the potential downstream role of FGF23, are unclear. Therefore, we aimed to determine the associations between iron deficiency and higher EPO levels with mortality, and the potential mediating role of FGF23, in a cohort of community-dwelling subjects.

The Prevalence of Intradialytic Hypotension in Patients on Conventional Hemodialysis: A Systematic Review with Meta-Analysis.

Background: Intradialytic hypotension (IDH) is considered to be a frequent complication of hemodialysis (HD) and is associated with symptom burden, increased incidence of access failure, cardiovascular events, and higher mortality. This systematic literature review aims to analyse studies that investigated the prevalence of IDH. A complicating factor herein is that many different definitions of IDH are used in literature.

Association between quality of life and various aspects of intradialytic hypotension including patient-reported intradialytic symptom score.

Background: There is increasing awareness that, besides patient survival, Quality of Life (QOL) is a relevant outcome factor for patients who have a chronic disease. In haemodialysis (HD) patients, intradialytic hypotension (IDH) is considered one of the most frequent complications, and this is often accompanied by symptoms. Several studies have investigated QOL in dialysis patients, however, research on the association between intradialytic symptoms and QOL is minimal.

The EPO-FGF23 Signaling Pathway in Erythroid Progenitor Cells: Opening a New Area of Research.

We provide an overview of the evidence for an erythropoietin-fibroblast growth factor 23 (FGF23) signaling pathway directly influencing erythroid cells in the bone marrow. We outline its importance for red blood cell production, which might add, among others, to the understanding of bone marrow responses to endogenous erythropoietin in rare hereditary anemias. FGF23 is a hormone that is mainly known as the core regulator of phosphate and vitamin D metabolism and it has been recognized as an important regulator of bone mineralization.

Association of plasma somatostatin with disease severity and progression in patients with autosomal dominant polycystic kidney disease.

Background: Somatostatin (SST) inhibits intracellular cyclic adenosine monophosphate (cAMP) production and thus may modify cyst formation in autosomal dominant polycystic kidney disease (ADPKD). We investigated whether endogenous plasma SST concentration is associated with disease severity and progression in patients with ADPKD, and whether plasma SST concentrations change during treatment with a vasopressin V2 receptor antagonist or SST analogue.

Methods: In this observational study, fasting concentrations of SST were measured in 127 ADPKD patients (diagnosed upon the revised Ravine criteria) by ELISA.

Changes in cerebral oxygenation and cerebral blood flow during hemodialysis - A simultaneous near-infrared spectroscopy and positron emission tomography study.

Near-infrared spectroscopy (NIRS) is used to monitor cerebral tissue oxygenation (rSO) depending on cerebral blood flow (CBF), cerebral blood volume and blood oxygen content. We explored whether NIRS might be a more easy applicable proxy to [O]HO positron emission tomography (PET) for detecting CBF changes during hemodialysis. Furthermore, we compared potential determinants of rSO and CBF.

Kidney Function Reserve Capacity in Early and Later Stage Autosomal Dominant Polycystic Kidney Disease.

Background And Objectives: It is assumed that in autosomal dominant polycystic kidney disease (ADPKD), kidney function remains in the normal range for several decades because of hyperfiltration of remnant nephrons. In this study, we investigate the extent to which patients with ADPKD hyperfilter.

Design, Setting, Participants, & Measurements: In this cross-sectional study, we measured GFR as urinary clearance using continuous infusion of I-iothalamate.

Switching iron sucrose to ferric carboxymaltose associates to better control of iron status in hemodialysis patients.

Background: Although the efficacy of iron sucrose (IS) and ferric carboxymaltose (FCM) in treating anemia in hemodialysis (HD) patients has been studied individually, a comparison of these two intravenous iron formulations has not yet been performed in HD patients.

Methods: We performed a retrospective audit on records of 221 stable HD patients from different HD centers in the Netherlands, who were switched from IS to FCM on a 1:1 ratio. To assess the effect of the switch on iron status parameters, data from 3 time points before and 3 time points after the switch were analyzed using linear mixed effects models.

Publisher Correction: Lower body mass index and mortality in older adults starting dialysis.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Association of different iron deficiency cutoffs with adverse outcomes in chronic kidney disease.

Background: Iron deficiency is highly prevalent in chronic kidney disease (CKD) patients. In clinical practice, iron deficiency is defined based on a combination of two commonly used markers, ferritin and transferrin saturation (TSAT). However, no consensus has been reached which cutoffs of these parameters should be applied to define iron deficiency.

Lower body mass index and mortality in older adults starting dialysis.

Lower body mass index (BMI) has consistently been associated with mortality in elderly in the general and chronic disease populations. Remarkably, in older incident dialysis patients no association of BMI with mortality was found. We performed an in-depth analysis and explored possible time-stratified effects of BMI.

Effect of plasma sodium concentration on blood pressure regulators during hemodialysis: a randomized crossover study.

Background: Intradialytic hypotension is a common complication of hemodialysis. The Hemocontrol biofeedback system, improving intradialytic hemodynamic stability, is associated with an initial transient increase in plasma sodium levels. Increases in sodium could affect blood pressure regulators.