Abstract
Background
Disordered mineral and bone metabolism is a common complication of chronic kidney disease (CKD). Bone biopsy remains the gold standard tool for evaluating renal osteodystrophy ...(ROD), but it is an invasive procedure. Despite a growing interest in the ability of newer bone biomarkers to discriminate between different forms of ROD, data on pre-dialysis patients are scarce.
Methods
A cross-sectional study was conducted in a cohort of 56 patients with CKD Stages 3 and 4. Participants underwent a transiliac bone biopsy after a course of double tetracycline labelling. Circulating levels of Wnt signalling inhibitors sclerostin and Dickkopf-1 (DKK1), soluble receptor activator of nuclear factor-κB ligand (sRANKL) and osteoprotegerin were measured and correlated with histomorphometric analysis results.
Results
Most patients had abnormal bone histology and low-turnover bone disease was the predominant form of ROD. Characteristics associated with high bone turnover were worse renal function, lower serum calcium and higher intact parathyroid hormone and fibroblast growth factor-23 levels. Patients with low bone turnover, on the other hand, presented with higher sclerostin along with lower DKK1 and sRANKL levels. In the multivariable logistic regression analysis, sclerostin and DKK1 levels were independently associated with low-turnover bone disease.
Conclusions
Our results suggest that circulating levels of Wnt signalling inhibitors sclerostin and DKK1 are predictive of low-turnover bone disease in patients not yet on dialysis. Further research is needed to assess the performance of these bone turnover biomarkers, compared with histomorphometric analysis, in the diagnosis and treatment monitoring of ROD.
Graphical Abstract
Graphical Abstract
There is scarce clinical experience with etelcalcetide in patients with secondary hyperparathyroidism uncontrolled with cinacalcet. The effect of etelcalcetide on serum sclerostin levels remains to ...be clarified.
Prospective cohort study in prevalent hemodialysis patients with uncontrolled sHPT under cinacalcet for at least 3 months, mean parathyroid hormone (PTH)>800pg/mL and calcium (Ca)>8.3mg/dL. Etelcalcetide 5mg IV/HD was initiated after cinacalcet washout. Levels of PTH, Ca, and phosphorus (Pi) followed monthly for 6 months. Plasma sclerostin levels measured before etelcalcetide treatment and after 6 months.
Thirty-four patients were enrolled, 19 (55.9%) male gender. Mean age 60.7 (± 12.3) years; median time on HD 82.5 (7–296) months and median cinacalcet dose was 180mg/week (Interquartile Range: 180–270).
Serum Ca, Pi and PTH levels showed a significant reduction after etelcalcetide treatment from 8.8mg/dL, 5.4mg/dL and 1005pg/mL to 8.1mg/dL (p=0.08), 4.9mg/dL (p=0.01) and 702pg/mL (p<0.001), respectively. Median etelcalcetide dose remained at 5mg/HD. Plasma sclerostin concentration increased from 35.66pmol/L (IQR11.94–54.58) to 71.05pmol/L (IQR54.43–84.91) (p<0.0001).
Etelcalcetide improved sHPT control in this group of patients, previously under cinacalcet treatment, and significantly increased plasma sclerostin concentration. The impact of etelcalcetide treatment on sclerostin levels is a novel finding.
Existe escasa experiencia clínica sobre el uso de etelcalcetida en pacientes con hiperparatiroidismo secundario no controlado con cinacalcet. Asimismo, el efecto de la etelcalcetida sobre los niveles de esclerostina aún no ha sido aclarado.
Realizamos un estudio de cohorte prospectivo en pacientes en hemodiálisis (HD) con hiperparatiroidismo secundario no controlado con cinacalcet durante al menos 3 meses, hormona paratiroidea media> 800 pg/ml y calcio (Ca)> 8,3mg/dl. Tras un periodo de lavado, se inició administración intravenosa de etelcalcetida 5mg/HD y se realizó un seguimiento mensual de los niveles de hormona paratiroidea, Ca y fósforo (Pi) durante 6 meses. Además, los niveles de esclerostina plasmática fueron medidos antes del tratamiento con etelcalcetida y después de 6 meses.
Se incluyeron 34 pacientes, 19 (55,9%) de sexo masculino. Edad media 60,7±12,3 años; la mediana de tiempo en HD fue 82,5 (7-296) meses y la mediana de la dosis de cinacalcet fue de 180mg/semana (rango intercuartílico 180-270).
Los niveles séricos de Ca, Pi y hormona paratiroidea mostraron una reducción significativa después del tratamiento con etelcalcetida desde 8,8mg/dl, 5,4mg/dl y 1005 pg/ml hasta 8,1mg/dl (p=0,08), 4,9mg/dl (p=0,01) y 702 pg/mL (p<0,001) respectivamente. La dosis media de etelcalcetida se mantuvo en 5mg/HD. La concentración de esclerostina plasmática aumentó de 35,66pmol/L (rango intercuartílico 11,94-54,58) a 71,05pmol/L (rango intercuartílico 54,43-84,91; p <0,0001).
En este grupo de pacientes previamente en tratamiento con cinacalcet, la etelcalcetida mejoró el control de hiperparatiroidismo secundario y resultó en un aumento de la concentración plasmática de esclerostina. El efecto del tratamiento con etelcalcetida sobre los niveles de esclerostina es un hallazgo novedoso.
Chronic kidney disease (CKD) patients present specific bone and mineral metabolism disturbances, which account for important morbidity and mortality. The term renal osteodystrophy, classically used ...for the nomination of CKD-associated bone disorder, has been limited to the histologic description of bone lesions, requiring the use of bone biopsy. Biochemical markers and imaging tools do not adequately predict the complex bone changes that are observed in renal osteodystrophy. Parathyroid hormone, which is a universally used biomarker of bone turnover in clinical practice, lacks specificity and sensitivity. Therefore, tetracycline double-labelled transiliac bone biopsy, with bone histology and histomorphometric evaluation, remains the best clinical tool to discriminate bone turnover and to evaluate the other dimensions of renal osteodystrophy. This review will focus on the value of classic bone histomorphometric analysis of trabecular bone in CKD patients and unfold new perspectives of this diagnostic tool, including cortical bone evaluation and bone tissue immunohistochemistry.
There is scarce clinical experience with etelcalcetide in patients with secondary hyperparathyroidism uncontrolled with cinacalcet. The effect of etelcalcetide on serum sclerostin levels remains to ...be clarified.
Prospective cohort study in prevalent hemodialysis patients with uncontrolled sHPT under cinacalcet for at least 3 months, mean parathyroid hormone (PTH)>800pg/mL and calcium (Ca)>8.3mg/dL. Etelcalcetide 5mg IV/HD was initiated after cinacalcet washout. Levels of PTH, Ca, and phosphorus (Pi) followed monthly for 6 months. Plasma sclerostin levels measured before etelcalcetide treatment and after 6 months.
Thirty-four patients were enrolled, 19 (55.9%) male gender. Mean age 60.7 (± 12.3) years; median time on HD 82.5 (7–296) months and median cinacalcet dose was 180mg/week (Interquartile Range: 180–270).
Serum Ca, Pi and PTH levels showed a significant reduction after etelcalcetide treatment from 8.8mg/dL, 5.4mg/dL and 1005pg/mL to 8.1mg/dL (p=0.08), 4.9mg/dL (p=0.01) and 702pg/mL (p<0.001), respectively. Median etelcalcetide dose remained at 5mg/HD. Plasma sclerostin concentration increased from 35.66pmol/L (IQR11.94–54.58) to 71.05pmol/L (IQR54.43–84.91) (p<0.0001).
Etelcalcetide improved sHPT control in this group of patients, previously under cinacalcet treatment, and significantly increased plasma sclerostin concentration. The impact of etelcalcetide treatment on sclerostin levels is a novel finding.
Existe escasa experiencia clínica sobre el uso de etelcalcetida en pacientes con hiperparatiroidismo secundario no controlado con cinacalcet. Asimismo, el efecto de la etelcalcetida sobre los niveles de esclerostina aún no ha sido aclarado.
Realizamos un estudio de cohorte prospectivo en pacientes en hemodiálisis (HD) con hiperparatiroidismo secundario no controlado con cinacalcet durante al menos 3 meses, hormona paratiroidea media> 800 pg/ml y calcio (Ca)> 8,3mg/dl. Tras un periodo de lavado, se inició administración intravenosa de etelcalcetida 5mg/HD y se realizó un seguimiento mensual de los niveles de hormona paratiroidea, Ca y fósforo (Pi) durante 6 meses. Además, los niveles de esclerostina plasmática fueron medidos antes del tratamiento con etelcalcetida y después de 6 meses.
Se incluyeron 34 pacientes, 19 (55,9%) de sexo masculino. Edad media 60,7±12,3 años; la mediana de tiempo en HD fue 82,5 (7-296) meses y la mediana de la dosis de cinacalcet fue de 180mg/semana (rango intercuartílico 180-270).
Los niveles séricos de Ca, Pi y hormona paratiroidea mostraron una reducción significativa después del tratamiento con etelcalcetida desde 8,8mg/dl, 5,4mg/dl y 1005 pg/ml hasta 8,1mg/dl (p=0,08), 4,9mg/dl (p=0,01) y 702 pg/mL (p<0,001) respectivamente. La dosis media de etelcalcetida se mantuvo en 5mg/HD. La concentración de esclerostina plasmática aumentó de 35,66pmol/L (rango intercuartílico 11,94-54,58) a 71,05pmol/L (rango intercuartílico 54,43-84,91; p <0,0001).
En este grupo de pacientes previamente en tratamiento con cinacalcet, la etelcalcetida mejoró el control de hiperparatiroidismo secundario y resultó en un aumento de la concentración plasmática de esclerostina. El efecto del tratamiento con etelcalcetida sobre los niveles de esclerostina es un hallazgo novedoso.
Renin-angiotensin-aldosterone system inhibitors (RAASi) are the cornerstone of treatment of heart failure with reduced ejection fraction (HFrEF). RAASi optimization in real-life care is challenged by ...hyperkalemia, a potentially fatal adverse event, which can necessitate downtitration or discontinuation of RAASi and negatively impact survival in HFrEF. The literature on this problem is sparse. We performed a systematic review of studies on HFrEF to investigate the prevalence, incidence, and risk factors of hyperkalemia, RAASi prescription rates, frequency of RAASi downtitration or discontinuation due to hyperkalemia, and the potential negative effect of the latter on prognosis.
We conducted a MEDLINE (PubMed) search including observational and interventional studies published between January 1987 and May 2018.
A total of 30 observational and 18 interventional studies were included in the review. The incidence of hyperkalemia reported was between 0% and 63% in observational studies and was between 0% and 30% in clinical trials. Risk factors for hyperkalemia included RAASi prescription, older age, diabetes, and chronic kidney disease. In real-life studies, RAASi were downtitrated or discontinued in 3-22% of HFrEF patients; hyperkalemia was the reported cause in 5% of cases. No reports were found on the impact on prognosis of RAASi downtitration or discontinuation due to hyperkalemia.
Hyperkalemia and RAASi downtitration or discontinuation are frequent, particularly in real-life HFrEF studies. Further research is needed to clarify the role of RAASi downtitration or discontinuation due to hyperkalemia and to assess its long-term prognostic impact in HFrEF patients.
Os inibidores do sistema renina-angiotensina-aldosterona (iSRAA) constituem pedras basilares para o tratamento da insuficiência cardíaca com fração de ejeção reduzida (IC-FER). A otimização dos iSRAA é dificultada pela ocorrência de hipercalemia, que obriga à redução/interrupção do iSRAA, podendo impactar negativamente na sobrevivência dos doentes com IC-FER. Esta questão é raramente abordada na literatura.
Realizámos uma revisão sistemática dos estudos sobre doentes com IC-FER para investigar a prevalência, incidência e fatores de risco para hipercaliemia, frequência de utilização de iSRAA, frequência de redução/interrupção dos iSRAA por hipercaliemia e o possível impacto negativo da redução/interrupção dos iSRAA no prognóstico. A pesquisa foi feita na Medline (PubMed) incluindo estudos observacionais e interventivos publicados entre janeiro de 1987 e maio de 2018.
Foram incluídos 30 estudos observacionais e 18 interventivos. A frequência relatada de hipercalemia variou entre 0% e 63% em estudos observacionais e entre 0% e 30% em ensaios clínicos. Fatores de risco para hipercalemia incluíram uso de iSRAA, idade avançada, diabetes e doença renal crónica. Em estudos de vida real, os iSRAA foram interrompidos em 3% a 22% dos doentes com IC-FER, sendo a hipercalemia a causa em 5% destes casos. Não foram encontrados relatos do impacto prognóstico da redução/interrupção dos iSRAA devida à hipercalemia.
A hipercaliemia e redução/interrupção dos iSRAA são frequentes, principalmente em estudos de vida real de IC-FER. Novos estudos serão necessários para esclarecer o papel da redução/interrupção dos iSRAA devida a hipercalemia e para avaliar o seu impacto prognóstico a longo prazo em doentes com IC-FER.
Renin–angiotensin–aldosterone system inhibitors (RAASi) reduce morbidity and mortality in heart failure (HF) with reduced ejection fraction in a dose-dependent manner. They also have a positive ...impact in other cardiovascular diseases (CVDs). However, RAASi may induce hyperkalemia, a potentially life-threatening disorder. This risk is further increased in those with concomitant chronic kidney disease, diabetes mellitus, and/or in patients with hypertension. Current treatment guidelines recommend maximal RAASi dosing to improve clinical outcomes; however, this is often limited by the development of hyperkalemia. When this occurs, current guidelines recommend RAASi down-titration/interruption, which, while improving short-term prognosis, is associated with a negative long-term prognostic impact. At present, the European Society of Cardiology suggests the consideration of novel potassium binders (patiromer and sodium zirconium cyclosilicate) for the management of RAASi-associated hyperkalemia. Both drugs can reduce serum potassium levels and prevent recurrent hyperkalemia. Additionally, patiromer showed enabling of RAASi optimization in high-risk patients. Nevertheless, precise recommendations on the use of these drugs are lacking. Building upon current HF guideline recommendations, a multidisciplinary expert panel convened to design an algorithm providing practical guidance on the use of novel potassium binders/patiromer in patients with HF and/or other CVD. As a result of that effort, we present an evidence-based treatment algorithm for the management of hyperkalemia with novel potassium binders/patiromer in patients with HF and/or other CVD receiving RAASi, including the necessary monitoring to avoid induction of hypokalemia. This algorithm aims to maintain or up-titrate RAASi to optimized doses, while maintaining normokalemia, improved clinical outcomes, and long-term prognosis.
Calcitriol and calcimimetics are used to treat hyperparathyroidism secondary to chronic kidney disease (CKD). Calcitriol administration and the subsequent increase in serum calcium concentration ...decrease parathyroid hormone (PTH) levels, which should reduce bone remodeling. We have previously reported that, when maintaining a given concentration of PTH, the addition of calcimimetics is associated with an increased bone cell activity. Whether calcitriol administration affects bone cell activity while PTH is maintained constant should be evaluated in an animal model of renal osteodystrophy. The aim of the present study was to compare in CKD PTH‐clamped rats the bone effects of calcitriol and calcimimetic administration. The results show that the administration of calcitriol and calcimimetic at doses that induced a similar reduction in PTH secretion produced dissimilar effects on osteoblast activity in 5/6 nephrectomized (Nx) rats with secondary hyperparathyroidism and in Nx rats with clamped PTH. Remarkably, in both rat models, the administration of calcitriol decreased osteoblastic activity, whereas calcimimetic increased bone cell activity. In vitro, calcitriol supplementation inhibited nuclear translocation of β‐catenin and reduced proliferation, osteogenesis, and mineralization in mesenchymal stem cells differentiated into osteoblasts. In conclusion, besides the action of calcitriol and calcimimetics at parathyroid level, these treatments have specific effects on bone cells that are independent of the PTH level.
In vivo studies used 5/6 nephrectomy with parathyroidectomy and replacement of exogenous PTH to eliminate the osteogenic effect of PTH comparing the bone effects of calcitriol vs calcimimetic. The osteogenesis of mesenchymal stem cells in presence of calcitriol was also evaluated. Results show calcimimetic increases bone formation, while calcitriol reduces it. In vitro, calcitriol presence reduces mineralization and osteogenesis of stem cells into osteoblasts. In this experimental study and independently of PTH, we demonstrate that calcitriol administration reduces bone formation.
Bone disease after kidney transplant (KT) results from multiple factors, including previous bone and mineral metabolism disturbances and effects of transplant-related medications. New biomolecules ...have been recently associated with the development and progression of the chronic kidney disease-associated bone and mineral disorder (CKD-MBD). These include sclerostin and the soluble receptor activator of nuclear factor-kB ligand (sRANKL).
To better understand the role of biomarkers in post-transplant bone disease, this study was designed to prospectively evaluate and correlate results from the histomorphometric analysis of bone biopsies after KT with emerging serum biomarkers of the CKD-MBD: sclerostin, Dickkopf-related protein 1 (Dkk-1), sRANKL and osteo-protegerin (OPG).
Our data shows a significant increase in plasma levels of bioactive sclerostin after KT accompanied by a significant reduction in plasma levels of Dkk-1, suggesting a promotion of the inhibition of bone formation by osteoblasts through the activation of these inhibitors of the Wnt signaling pathway. In addition, we found a significant increase in plasma levels of free sRANKL after KT accompanied by a significant reduction in plasma levels of its decoy receptor OPG, suggesting an enhanced bone resorption by osteoclasts mediated by this mechanism.
Taken together, these results suggest that the loss of bone volume observed after KT could be explain mainly by the inhibition of bone formation mediated by sclerostin accompanied by an enhanced bone resorption mediated by sRANKL.
Disturbances in mineral metabolism play a central role in the development of renal bone disease. In a 54-wk, randomized, open-label study, 119 hemodialysis patients were enrolled to compare the ...effects of sevelamer hydrochloride and calcium carbonate on bone. Biopsy-proven adynamic bone disease was the most frequent bone abnormality at baseline (59%). Serum phosphorus, calcium, and intact parathyroid hormone were well controlled in both groups, although calcium was consistently lower and intact parathyroid hormone higher among patients who were randomly assigned to sevelamer. Compared with baseline values, there were no changes in mineralization lag time or measures of bone turnover (e.g., activation frequency) after 1 yr in either group. Osteoid thickness significantly increased in both groups, but there was no significant difference between them. Bone formation rate per bone surface, however, significantly increased from baseline only in the sevelamer group (P = 0.019). In addition, of those with abnormal microarchitecture at baseline (i.e., trabecular separation), seven of 10 in the sevelamer group normalized after 1 yr compared with zero of three in the calcium group. In summary, sevelamer resulted in no statistically significant changes in bone turnover or mineralization compared with calcium carbonate, but bone formation increased and trabecular architecture improved with sevelamer. Further studies are required to assess whether these changes affect clinical outcomes, such as rates of fracture.
Introduction Adults with end-stage kidney disease (ESKD) treated with haemodialysis experience mortality of between 15% and 20% each year. Effective interventions that improve health outcomes for ...long-term dialysis patients remain unproven. Novel and testable determinants of health in dialysis are needed. Nutrition and dietary patterns are potential factors influencing health in other health settings that warrant exploration in multinational studies in men and women treated with dialysis. We report the protocol of the “DIETary intake, death and hospitalisation in adults with end-stage kidney disease treated with HaemoDialysis (DIET-HD) study,” a multinational prospective cohort study. DIET-HD will describe associations of nutrition and dietary patterns with major health outcomes for adults treated with dialysis in several countries. Methods and analysis DIET-HD will recruit approximately 10 000 adults who have ESKD treated by clinics administered by a single dialysis provider in Argentina, France, Germany, Hungary, Italy, Poland, Portugal, Romania, Spain, Sweden and Turkey. Recruitment will take place between March 2014 and June 2015. The study has currently recruited 8000 participants who have completed baseline data. Nutritional intake and dietary patterns will be measured using the Global Allergy and Asthma European Network (GA2LEN) food frequency questionnaire. The primary dietary exposures will be n-3 and n-6 polyunsaturated fatty acid consumption. The primary outcome will be cardiovascular mortality and secondary outcomes will be all-cause mortality, infection-related mortality and hospitalisation. Ethics and dissemination The study is approved by the relevant Ethics Committees in participating countries. All participants will provide written informed consent and be free to withdraw their data at any time. The findings of the study will be disseminated through peer-reviewed journals, conference presentations and to participants via regular newsletters. We expect that the DIET-HD study will inform large pragmatic trials of nutrition or dietary interventions in the setting of advanced kidney disease.
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