KDIGO 2017 Clinical Practice Guideline Update for the Diagnosis, Evaluation, Prevention, and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD)

Advance care planning to patients with chronic kidney disease and their families: An intervention development study

AIM

To develop an advance care planning intervention based on the needs of patients with chronic kidney disease, families and healthcare professionals.

BACKGROUND

Patients with chronic kidney disease and their families request early advance care planning that continues throughout their illness trajectory. Healthcare professionals experience barriers to initiating advance care planning. Involvement of stakeholders in development of health interventions is important, to identify priorities, understand the problem and find solutions.

METHOD

The development was inspired by the Medical Research Council's framework, and codesign was applied. One future workshop and one design workshop were conducted with the consumers. The process was iterative, and data were analysed using the action research spiral. The Guidance for reporting intervention development studies in healthcare (GUIDED) was used.

RESULTS

Five areas were considered significant to an advance care planning intervention; a biopsychosocial approach, early palliative care, a family-focused approach, early and continuous advance care planning and a consumer-centred approach. Based on these, a conversation process with healthcare professionals was designed to give patients and families the opportunity to share values, preferences and wishes for treatment and their family and everyday life.

CONCLUSION

Codesign facilitated a collaborative process that allowed the consumers to have a significant impact on the design of an advance care planning intervention. A conversation process concerning everyday life, illness and treatment was designed for patients and families. The intervention included an advance care planning tool to guide the healthcare professionals.

PRACTICE IMPLICATIONS

The intervention has the intention to improve the communication between healthcare professionals, patients and families. The study provides important knowledge about the significance of giving the patients and their families support in sharing their values, preferences and wishes for treatment and everyday life, thus, to improve care and treatment in their illness trajectory.

IMPACT

What problem did the study address Patients with chronic kidney disease and their families strongly request early initiation of advance care planning that continues throughout the illness trajectory. Healthcare professionals experience barriers to the initiation of the advance care planning and request a more systematic approach. What were the main findings Development of a conversation process about everyday life, illness and treatment for patients diagnosed with chronic kidney disease and families, including an advance care planning tool to guide the healthcare professionals. Where and on whom will the research have an impact The study contributes an advance care planning intervention to patients in the early stages of chronic kidney disease and their families. We believe that the intervention could be included during consultations with healthcare professionals in other stages of chronic kidney disease as well as other chronic disease.

REPORTING METHOD

To strengthen the reporting of the development of the advance care planning intervention, we used the Guidance for reporting intervention development studies in healthcare (GUIDED).

PATIENT OR PUBLIC CONTRIBUTION

The development of the intervention in this study was a collaborative process between patients, families, healthcare professionals and representatives from the Danish Kidney Association, the department's user council and the research team.

Effect of Antidiabetic Drugs on Bone Health in Patients with Normal Renal Function and in Chronic Kidney Disease (CKD): Insight into Clinical Challenges in the Treatment of Type 2 Diabetes

Among the metabolic changes occurring during the course of type 2 diabetes (T2DM) and diabetic kidney disease (DKD), impaired bone health with consequent increased fracture risk is one of the most complex and multifactorial complications. In subjects with diabetic kidney disease, skeletal abnormalities may develop as a consequence of both conditions. In the attempt to define a holistic approach to diabetes, potential effects of various classes of antidiabetic drugs on the skeleton should be considered in the setting of normal kidney function and in DKD. We reviewed the main evidence on these specific topics. Experimental studies reported potential beneficial and harmful effects on bone by different antidiabetics, with few data available in DKD. Clinical studies specifically designed to evaluate skeletal effects of antidiabetics have not been performed; notwithstanding, data gleaned from randomized controlled trials and intervention studies did not completely confirm observations made by basic research. In the aggregate, evidence from meta-analyses of these studies suggests potential positive effects on fracture risk by metformin and glucagon-like peptide-1 receptor agonists, neutral effects by dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter-2 inhibitors, and sulfonylureas, and negative effects by insulin and thiazolidinediones. As no clinical recommendations on the management of antidiabetic drugs currently include fracture risk assessment among the main goal of therapy, we propose an integrated approach with the aim of defining a patient-centered management of diabetes in chronic kidney disease (CKD) and non-CKD patients. Future clinical evidence on the skeletal effects of antidiabetics will help in optimizing the approach to a personalized and more effective therapy of diabetes.

Advantages of total parathyroidectomy in patients with secondary hyperparathyroidism induced by end stage renal disease

Introduction

Secondary hyperparathyroidism, as a result of chronic kidney disease could be treated medically or surgically. When pharmacotherapy fails, patients undergo surgery - parathyroidectomy, the curative treatment of secondary hyperparathyroidism (SHPT). There are currently 3 accepted surgical techniques, each with supporters or opponents - total parathyroidectomy, subtotal parathyroidectomy and parathyroidectomy with immediate autotransplantation.

Methods

In this paper we described our experience on a series of 160 consecutive patients diagnosed with secondary hyperparathyroidism who underwent surgery, in 27 cases it was totalization of the intervention (patients with previously performed subtotal parathyroidectomy or with supernumerary glands and SHPT recurrence). We routinely perform total parathyroidectomy, the method that we believe offers the best results.

Results

The group of patients was studied according to demographic criteria, paraclinical balance, clinical symptomatology, pre- and postoperative iPTH (intact parathormone) values, SHPT recurrence, number of reinterventions. In 31 cases we found gland ectopy and in 15 cases we discovered supernumerary parathyroids. A percentage of 96.24% of patients with total parathyroidectomy did not show recurrence.

Discussions

After analyzing the obtained results, our conclusion was that total parathyroidectomy is the intervention of choice for patients suffering from secondary hyperparathyroidism when pharmacotherapy fails in order to prevent recurrence of the disease and to correct the metabolic parameters.

Renal complications in chronic hypoparathyroidism - a systematic cross-sectional assessment

Context

Although renal long-term complications are acknowledged in chronic hypoparathyroidism (HPT), standardized investigations are scarce.

Objective

To systematically investigate renal complications and their predictors in hypoparathyroid patients compared to matched individuals.

Design

Prospective observational study in 161 patients with chronic HPT.

Methods

Patients received renal ultrasound, clinical and laboratory assessments. An individual 1:3 matching with participants from the German population-based Study of Health in Pomerania was performed.

Results

Of 161 patients (92% postoperative HPT), prevalence of eGFR <60ml/min/1.73m2 was 21%, hypercalciuria 41%. Compared to healthy individuals, HPT patients had a significantly lower eGFR (74.2 vs. 95.7 ml/min/1.73m², p<0.01). Renal ultrasound revealed calcifications in 10% (nephrocalcinosis in 7% and calculi in 3%). Patients with renal calcifications had higher levels of 24-hour urine calcium excretion (8.34 vs. 5.08 mmol/d, p=0.02), spot urine calcium excretion (4.57 vs. 2.01 mmol/L, p=0.01) and urine calcium-to-creatinine ratio (0.25 vs. 0.16, p<0.01) than patients without calcifications. Albumin-corrected calcium, phosphate, calcium-phosphate product, 25-hydroxyvitamin D in serum, eGFR, daily calcium intake or disease duration were not significantly different between these two groups. Including patients receiving rhPTH therapy, a lower serum phosphate concentration (odds ratio 1.364 [95% confidence interval (CI) 1.049-1.776], p<0.05) and a longer disease duration of HPT (odds ratio 1.063 [95% CI 1.021-1.106], p<0.01) were significant predictors for renal calcifications. Excluding patients receiving rhPTH therapy, a higher 24-hour urine calcium excretion (odds ratio 1.215 [95% CI 1.058-1.396], p<0.01) was a significant predictor for renal calcifications but not serum magnesium or disease duration.

Conclusions

Prevalence of impaired renal function among patients with chronic HPT is increased and independent from visible renal calcifications. Depending on exclusion of patients with rhPTH therapy, regression analysis revealed disease duration and serum phosphate or disease duration and 24-hour urinary calcium excretion as predictors for renal calcifications.

Clin Trials Identifier

NCT05585593.

Bone Disorders in Pediatric Chronic Kidney Disease: A Literature Review

Intense changes in mineral and bone metabolism are frequent in chronic kidney disease (CKD) and represent an important cause of morbidity and reduced quality of life. These disorders have conventionally been defined as renal osteodystrophy and classified based on bone biopsy, but due to a lack of bone biopsy data and validated radiological methods to evaluate bone morphology in children, it has been challenging to effectively assess renal osteodystrophy in pediatric CKD; the consequence has been the suboptimal management of bone disorders in children. CKD-mineral and bone disorder (CKD-MBD) is a new expression used to describe a systemic disorder of mineral and bone metabolism as a result of CKD. CKD-MBD is a triad of biochemical imbalances in calcium, phosphate, parathyroid hormone, and vitamin D; bone deformities and soft tissue calcification. This literature review aims to explore the pathogenesis, diagnostic approach, and treatment of CKD-MBD in children and the effects of renal osteodystrophy on growing skeleton, with a specific focus on the biological basis of this peculiar condition.

The Relationship Between C-Reactive Protein (CRP) Concentrations and Erythropoietin Resistance, Hospital Admission Rate, Control of Mineral Metabolism, and Comorbidity in Hemodialysis Patients

Background End-stage kidney disease patients undergoing hemodialysis are prone to develop inflammation detected by high serum C-reactive protein (CRP) levels. This study highlights the association between CRP and the erythropoietin resistance index, hospital admission rate, control of mineral metabolism, and comorbidities in a tertiary hospital and two dialysis centers in Saudi Arabia. Objectives The objective of the study is to assess the relationship between CRP levels and hemoglobin level, hospital admission rate, mineral metabolism, and comorbidity in hemodialysis patients. Materials and methods This was a cross-sectional study conducted at King Abdulaziz Medical City Dialysis Center and the South and North Dialysis Centers of King Abdullah Dialysis Program in Riyadh. All hemodialysis adult patients who have been on dialysis for over six months were included. Patients with acute illnesses and pediatric patients were excluded. The association between CRP and other variables was reported using the Pearson correlation test. The calculated sample size was 218 by using the Raosoft website; however, the final number we analyzed was 209 after exclusion. Results The prevalence of a high level of CRP was more common among patients with diabetes mellitus (p=0.008) and those who were using antihypertensives (p=0.044) while the prevalence of a high level of CRP was less common among underweight patients (p=0.031) and hepatitis C virus (HCV)-positive patients (p=<0.001). The mean value of Kt/V was significantly lower among patients with a high level of CRP (p=0.009). HCV negative was the only independent significant risk factor associated with high CRP concentration (p=0.006). Conclusions In conclusion, there was an association between CRP levels with BMI, diabetics, the use of antihypertensive medications, and negative or undetectable HCV test results with the latter being the only independent significant factor. These data suggest that patients meeting these characteristics are in an inflammatory state and more prone to develop complications; thus, implementing CPR testing in this population might be useful. Other reviews showing causations are needed to further elucidate.

Trabecular Bone Score in Assessing Bone Mineralization Status in Children with End- Stage Renal Disease: A Promising Tool

Areal-bone mineral density (aBMD) of lumbar-spine dual energy X-ray absorptiometry (DXA) scan is the most frequently used tool in evaluating BMD in pediatric patients, however its size dependency have significant impact on measurements accuracy in children with chronic kidney disease (CKD). This study aimed to evaluate the usefulness of trabecular bone score (TBS) computed during lumbar-spine DXA scan in assessing bone status in children on maintenance hemodialysis (HD). Ninety-three children on HD (aged 9-18 years) were subjected to lumbar-spine DXA-scan to obtain aBMD (g/cm2) and TBS.Z-scores of aBMD for chronological-age (aBMDZ-CA), height-age (aBMDZ-HA), and TBSZ-score were calculated using mean and SD values of 442 healthy controls. aBMD and TBS were significantly lower in short-for-age and normal height-for-age patients compared to the corresponding values of controls (p < 0.05 for all). Degraded vertebral microarchitecture (TBSZ-score < -2) was detected in 48% and 44% of male and female patients respectively. There were no significant differences in median TBSZ-score between short-for-age and normal height-for-age HD patients in male (p = 0.425) and in female (p = 0.316) patients. TBSZ-score correlated significantly with aBMDZ-CA (r = 0.234; p = 0.024) but not with aBMDZ-HA (r = 0.077; p = 0.462). Patients with history of fractures (5 patients only) had significantly lower TBS scores compared to those without fracture history (p = 0.016).

CONCLUSION

TBS is significantly reduced in children on maintenance HD and is associated with increased fracture incidence. TBS has shown to be a promising tool in assessing bone quality (trabecular microarchitecture) in children with CKD being not size-dependent as is a-BMD, for further evaluation of its potential role in therapeutic and follow-up decisions.

WHAT IS KNOWN

• In children with CKD, bone demineralization starts as early as CKD stage 2, so assessment of bone health is mandatory for follow up and therapeutic decisions. • aBMD of lumbar-spine DXA scan is the most used tool in evaluating BMD in pediatric patients, however its size dependency have significant impact on measurements made in children with CKD.

WHAT IS NEW

• TBS is significantly reduced in children on maintenance HD and associated with increased fracture incidence. • TBS has shown to be a promising tool in assessing bone quality (trabecular microarchitecture) in children with CKD being not size-dependent as is a-BMD.

Clinical Implication of Consistently Strict Phosphate Control for Coronary and Valvular Calcification in Incident Patients Undergoing Hemodialysis

AIMS

Serum phosphate control is crucial for the progression of vascular and valvular calcifications. Strict phosphate control is recently suggested; however, there is a lack of convincing evidence. Therefore, we explored the effects of strict phosphate control on vascular and valvular calcifications in incident patients undergoing hemodialysis.

METHODS

A total of 64 patients undergoing hemodialysis from our previous randomized controlled trial were included in this study. Coronary artery calcification score (CACS) and cardiac valvular calcification score (CVCS) were evaluated using computed tomography and ultrasound cardiography at baseline and 18 months after the initiation of hemodialysis. The absolute changes in CACS (ΔCACS) and CVCS (ΔCVCS) and the percent change in CACS (%ΔCACS) and CVCS (%ΔCVCS) were calculated. Serum phosphate level was measured at 6, 12, and 18 months after the initiation of hemodialysis. Moreover, phosphate control status was evaluated using the area under the curve (AUC) by the amount of time spent with a serum phosphate level of ≥ 4.5 mg/dL and the extent to which this threshold exceeded over the observation period.

RESULTS

ΔCACS, %ΔCACS, ΔCVCS, and %ΔCVCS were significantly lower in the low AUC group than in the high AUC group. ΔCACS and %ΔCACS were also significantly lower. ΔCVCS and %ΔCVCS tended to be lower in patients whose serum phosphate level never exceeded 4.5 mg/dL than in those whose serum phosphate level continuously exceeded 4.5 mg/dL. AUC significantly correlated with ΔCACS and ΔCVCS.

CONCLUSION

Consistently strict phosphate control may slow the progression of coronary and valvular calcifications in incident patients undergoing hemodialysis.

Real-World Experience of Using Etelcalcetide for Secondary Hyperparathyroidism in Community-Based Hemodialysis Centers in Singapore

Introduction Chronic kidney disease-related mineral and bone disorder (CKD-MBD), characterized by abnormalities in calcium, phosphate, and parathyroid hormone metabolism, with impaired bone turnover and extravascular calcification is a known complication of advanced chronic kidney disease (CKD). Secondary hyperparathyroidism (SHPT) develops early in the disease and its prevalence gradually increases with the disease progression, becoming almost universal in patients with end-stage renal disease (ESRD). The treatment for SHPT includes synthetic vitamin D analogs, calcitriol or calcimimetics. Recently, intravenous etelcalcetide was introduced as a second-generation calcimimetic. This article provides the real-world experience of using etelcalcetide in multiethnic Asian patients receiving hemodialysis at community-based hemodialysis centers in Singapore. Methods This study was real-world evidence, generated by a retrospective clinical audit of routine clinical care of hemodialysis patients in community-based centers in Singapore who received etelcalcetide for treating SHPT. The information on the starting and maximum dose of etelcalcetide, duration of treatment on hemodialysis, parathyroid hormone (PTH) levels, dialysate calcium, concomitant medications, and reasons for discontinuation were collected from the medical records. PTH levels were collected at four-, eight-, and twelve-month intervals. Results A total of 148 patients received etelcalcetide during the study period. Ten patients died and twenty discontinued their treatment, with 118 patients remaining on treatment. Demographically, the patients included Chinese, Malay, Indians, and those belonging to other racial groups. The starting dose of etelcalcetide ranged from 2.5 mg once per week to 7.5 mg three times a week. There was a 16.8% reduction (p=<0.001) in intact-PTH after four months of therapy. Target intact-PTH level of less than 60 pmol/L, was reported as 1.4% at baseline, with 22.3% at four months (p<0.001) and 25.9% at eight months (p=0.028). Calcium and phosphate levels were also tracked as part of the safety and efficacy measures of using etelcalcetide. No symptomatic hypocalcemia was noted and phosphate levels were noted to decline significantly. Overall, the calcium-phosphate product reduced at four months (13.2%, p=<0.001) and eight months (12.7%, p<0.05). An analysis of concomitant medication usage, dialysate calcium utilized, and the side effects of etelcalcetide were also recorded. Finally, a brief descriptive analysis of the patient's subjective feedback regarding etelcalcetide was also reported, especially regarding the reduction in pill burden and overall compliance to medications. Conclusion Etelcalcetide is safe and effective for treating SHPT in multi-ethnic Asian hemodialysis patients and can be considered an alternative to oral cinacalcet. Our study showed no side effects, which was one of the key reasons for non-compliance to traditional calcimimetics. A favorable compliance profile with reduced pill burden was noted by using this intravenous calcimimetic.

Frequency and determinants of serum calcium monitoring during eldecalcitol therapy in patients with osteoporosis

INTRODUCTION

Eldecalcitol (ELD) is an active vitamin D3 analog (AVD) commonly used to treat osteoporosis in Japan. Although routine monitoring of serum calcium levels during ELD therapy is recommended, little is known about the actual frequency and determinants of monitoring.

MATERIALS AND METHODS

This was a descriptive cohort study using a Japanese electronic medical records database. We identified osteoporosis patients who initiated treatment with ELD or other AVDs (alfacalcidol and calcitriol) between April 1, 2011 and September 10, 2021. The index date for cohort entry was the first prescription date of ELD or other AVDs. The frequency of serum calcium monitoring was evaluated every 6 months. Determinants of serum calcium monitoring were identified using multivariable logistic regression models. We also calculated the incidence of hypercalcemia and the frequency of serum calcium monitoring within 6 months before hypercalcemia.

RESULTS

We identified 12,671 ELD users and 7867 other AVD users. Within 6 months after cohort entry, 45.9% of ELD users and 58.7% of other AVD users underwent serum calcium monitoring. Female sex, no use of systemic corticosteroids, moderate-to-good renal function, treatment in smaller hospitals, and treatment in orthopedic surgery departments were associated with a lower likelihood of receiving serum calcium monitoring during ELD therapy. The incidence of hypercalcemia among ELD users was 6.36 per 100 person-years, with 20.6% of cases not receiving serum calcium monitoring before hypercalcemia.

CONCLUSION

Our findings suggest that serum calcium monitoring is not given adequate attention during ELD therapy in routine clinical practice.

Tenapanor Improves Long-Term Control of Hyperphosphatemia in Patients Receiving Maintenance Dialysis: the NORMALIZE Study

Key Points

Tenapanor is a first-in-class, minimally systemic sodium–hydrogen exchanger 3 inhibitor with a mechanism of action distinct from phosphate binders. Tenapanor alone or with phosphate binders led to 35%–49% of patients achieving serum phosphate ≤4.5 mg/dl over an 18-month period versus 22% at baseline. Tenapanor alone or with phosphate binders may help adults with CKD on maintenance dialysis achieve normal serum phosphate concentrations.

Background

Most patients with ESKD and hyperphosphatemia have difficulty controlling serum phosphate (sP) concentrations despite maintenance dialysis, dietary restriction, and phosphate binder treatment. NORMALIZE evaluated the efficacy and safety of tenapanor 30 mg twice daily alone or in combination with phosphate binders to achieve sP within the adult population reference range (2.5–4.5 mg/dl).

Methods

Patients who completed the Phase 3 PHREEDOM study could enroll in NORMALIZE. Patients enrolled in NORMALIZE who had received tenapanor during the PHREEDOM study (n =111) added sevelamer carbonate if sP was >4.5 mg/dl. Patients who had received sevelamer carbonate during the PHREEDOM study (n =61) added tenapanor and decreased sevelamer carbonate if sP was ≤4.5 mg/dl, per protocol titration schedule. Patients were followed in NORMALIZE for up to 18 months. We assessed efficacy in the full analysis set, defined as patients who received ≥1 dose of study drug and had ≥1 post-treatment sP measurement (n =171). We assessed safety in all patients who received ≥1 dose of study drug (n =172).

Results

At the end point visit, 57 of 171 patients (33%) in the full analysis set achieved sP between 2.5 and 4.5 mg/dl. Eight of 23 patients (35%) who were on tenapanor alone at the end point visit achieved sP between 2.5 and 4.5 mg/dl. The mean reduction from PHREEDOM baseline to end of NORMALIZE in sP was 2.0 mg/dl. Serum intact fibroblast growth factor-23 was significantly reduced; serum intact parathyroid hormone was significantly reduced among patients with intact parathyroid hormone ≥300 pg/ml at PHREEDOM baseline. The most commonly reported treatment-emergent adverse event was diarrhea in 38 of 172 patients (22%), which led to tenapanor discontinuation in four patients (2%).

Conclusions

Tenapanor alone or in combination with phosphate binders helped adult patients on maintenance dialysis achieve normal sP concentrations. Safety was consistent with previous studies of tenapanor.

Clinical trial registry name and registration number

A Long-Term Study to Evaluate the Ability of Tenapanor Alone or in Combination With Sevelamer to Treat to Goal Serum Phosphorus in Patients With ESKD on Dialysis (NORMALIZE), NCT03988920 .

Managing Phosphate Burden in Patients Receiving Dialysis: Beyond Phosphate Binders and Diet

Most patients receiving dialysis rely on dietary restriction and phosphate binders to minimize the risk of hyperphosphatemia, which is associated with increased mortality. However, dietary restriction is difficult because of hidden phosphate additives in processed foods and medications. Restriction of dietary phosphate sources such as protein may increase the risk of malnutrition. Phosphate binders, the only pharmacologic option for phosphate management since aluminum salts were introduced several decades ago, are often insufficient for binding the 1400-2500 mg of phosphate potentially consumed daily. Over the last decade, serum phosphate levels in the United States have risen, and >69% of patients receiving dialysis exhibited a most recent phosphate level >4.5 mg/dl (above the normal range), indicating an urgent need for new, more effective therapies to manage phosphate burden. Novel, nonbinder therapies such as transcellular and paracellular phosphate absorption inhibitors may be used for phosphate management, and future studies should examine whether they allow fewer dietary restrictions for patients receiving dialysis, potentially improving patient quality of life and nutritional status. It is imperative that we collaborate to move beyond the restrictive approaches available today and provide patients and clinicians with an array of strategies so that they may choose the most appropriate patient-centered therapy.

Comparison of the Oral Calcimimetics Evocalcet and Cinacalcet in East Asian Patients on Hemodialysis with Secondary Hyperparathyroidism

Introduction

Evocalcet is an oral calcimimetic agent with proven efficacy and safety in treating secondary hyperparathyroidism (SHPT) in Japanese patients on dialysis.

Methods

This randomized, double-blind, intrapatient dose-adjustment, parallel-group, international multicenter study compared the efficacy and safety of evocalcet versus cinacalcet for 52 weeks in East Asian hemodialysis patients with SHPT.

Results

In total, 203 and 200 patients were randomized to receive evocalcet or cinacalcet, respectively (overall, 70.1% had baseline intact parathyroid hormone (PTH) levels ≥500 pg/ml, with no between-group difference). Mean percentage changes in intact PTH levels from baseline were -34.7% and -30.2% in the evocalcet and cinacalcet groups at 52 weeks (between-group difference -4.4%, 95% confidence interval [CI] -13.1%, 4.3%, below the predefined 15% noninferiority margin). Overall, 67.3% and 58.7% of patients in the evocalcet and cinacalcet groups, respectively, achieved ≥30% decrease in intact PTH levels from baseline (between-group difference 8.6%; 95% CI -1.8%, 19.1%). No major safety concerns were observed. Gastrointestinal adverse events (AEs) were significantly less frequent with evocalcet compared with cinacalcet (33.5% vs. 50.5%, P = 0.001), whereas the incidence of hypocalcemia did not differ.

Conclusion

Evocalcet might be a better alternative to cinacalcet for East Asian patients on hemodialysis with SHPT.

Treatment of Secondary Hyperparathyroidism and Posttransplant Tertiary Hyperparathyroidism

INTRODUCTION

Secondary hyperparathyroidism (sHPT) is prevalent in dialysis patients and can lead to tertiary hyperparathyroidism (tHPT) after kidney transplantation. We aimed to assess the association of pretransplant sHPT treatment on posttransplant outcomes.

METHODS

We reviewed kidney transplant patients treated with parathyroidectomy or cinacalcet for sHPT. We compared patients biochemical and clinical parameters, and outcomes based on sHPT treatment.

RESULTS

A total of 41 patients were included: 18 patients underwent parathyroidectomy and 23 patients received cinacalcet prior to transplantation. There were no significant differences between demographics, comorbidities, allograft characteristics or pre-sHPT intervention parathyroid hormone (PTH) and calcium levels. Patients that underwent parathyroidectomy were on dialysis for longer, although not significantly (71.9 versus 42.3 mo, P = 0.051). At time of transplantation, patients treated by parathyroidectomy had increased rates of controlled sHPT (88.9%; 16/18 versus 47.8%; 11/23, P = 0.008). Patients treated by parathyroidectomy had decreased development of tHPT (5.9%; 1/17; versus 42.1%; 8/19, P = 0.020) as well as decreased rates of posttransplant treatment with cinacalcet (11.1%; 2/18 versus 52.2%; 12/23, P = 0.008). Three patients treated with cinacalcet underwent parathyroidectomy after transplantation. Median PTH after transplant remained lower in patients treated by parathyroidectomy prior to transplant compared to those treated with cinacalcet (60.7 [interquartile range 39.7-133.4] versus 170.0 [interquartile range 128.4-292.7], P = 0.001). Allograft function and survival were similar for parathyroidectomy and cinacalcet, with median follow-up after transplantation of 56.7 and 34.2 mo, respectively.

CONCLUSIONS

sHPT treated by parathyroidectomy is associated with controlled PTH levels at transplantation and decreased rates of tHPT. Long-term outcomes should be studied on a larger scale.

Health effects of the New Nordic Renal Diet in patients with stage 3 and 4 chronic kidney disease, compared with habitual diet: a randomized trial

BACKGROUND

Chronic kidney disease (CKD) leads to an accumulation of waste products and causes adverse cardiometabolic effects.

OBJECTIVES

We investigated the health effects of the New Nordic Renal Diet (NNRD), a novel meal pattern reduced in phosphorus, protein, and sodium.

METHODS

A 26-wk randomized trial compared the NNRD with a habitual diet. The NNRD group received weekly home deliveries of food and recipes. Monthly study visits included fasting blood samples, 24-h urine samples, blood pressure, and anthropometric measurements. Intention-to-treat analysis used linear mixed-effects models.

RESULTS

Sixty patients, mean estimated glomerular filtration rate (eGFR) 34 mL/min/1.73 m2 and body mass index of 25-27 kg/m2, were included and 58 completed. Metabolic syndrome was present in 53% (NNRD group) and 57% (control group). The NNRD group (n = 30) reduced their 24-h urine phosphorus excretion by 19% (-153 mg; 95% confidence interval [CI]: -210, -95), control group (n = 30) (no change), between-group difference -171 mg (95% CI: -233, -109; P < 0.001). Proteinuria was reduced by 39% in the NNRD group (-0.33 g/d; 95% CI: -0.47, -0.18), control group (no change), between-group difference -0.34 g/d (95% CI: -0.52, -0.17; P < 0.001). Plasma urea was reduced by -1.5 mmol/L in the NNRD group (95% CI: -2.1, -0.9), control group (no change), between-group difference -1.4 mmol/L (95% CI: -2.0, -0.7; P < 0.001). Systolic blood pressure fell by -5.2 mmHg in the NNRD group (95% CI: -8.4, -2.1), control group (no change), between-group difference -3.9 mmHg (95% CI; -7.6, -0.2; P = 0.04). The NNRD group lost -1.7 kg (95% CI: -2.6, -0.8), control group (no change), between-group difference -2.0 kg (95% CI: -3.0, -1.0; P < 0.001). There were no effects on eGFR during the 26-wk intervention.

CONCLUSION

NNRD in moderate CKD reduces phosphorus excretion, proteinuria, systolic blood pressure, and weight, mainly by reducing abdominal fat. This trial was registered at clinicaltrials.gov as NCT04579315.

Mortality After Hip and Spine Fractures in Patients With End-Stage Kidney Disease: A Systematic Review and Meta-Analysis

Fractures represent a major cause of disability in the elderly, and patients with fractures exhibit a higher mortality rate than those without. Fractures are also an important health problem among patients with end-stage kidney disease (ESKD) requiring hemodialysis, peritoneal dialysis, or kidney transplantation. To the best of our knowledge, no study in the literature has yet quantitatively summarized the mortality rates, and a summary of evidence on post-hip and spine fracture mortality in patients with ESKD is lacking. The purpose of this study is to quantitatively evaluate the mortality rate, one-year mortality rate, and five-year mortality rate after hip and spine fractures in patients with ESKD receiving kidney replacement therapy. The MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and ClinicalTrials.gov databases were comprehensively searched for reports on mortality rate and time-period mortality in patients with ESKD after hip or spine fractures up to June 2022. Prospective and retrospective cohort studies, as well as case series involving four or more patients, were included. Pooled mortality rate, one-year rate, and five-year mortality rate with 95% confidence intervals (CIs) were examined using a random-effects model. The risk of bias was assessed using the Joanna Briggs Institute (JBI) Prevalence Critical Appraisal Tool. Additionally, heterogeneity between studies was evaluated. A total of 26 studies were included in this meta-analysis. The one-year and five-year mortality rates after hip and spine fractures were 215.35-774.0 per 1,000 person-year and 148-194.1 per 1,000 person-year, respectively. After hip fractures, the one-year mortality rate was 27% (95% CI: 18-38%, I2 = 98%), whereas the five-year mortality rate was 56% (95% CI: 41-71%, I2 = 99%). After spine fractures, the one-year mortality rate was 10% (95% CI: 4-17%, I2 = 70%), whereas the five-year mortality rate was 48.3%. The post-fracture mortality rate was high in patients with ESKD, particularly within one year after the occurrence of fractures. Additionally, the five-year mortality rate after hip femoral or spine fractures was high at approximately 50%.

Association between CKD-MBD and mortality in older patients with advanced CKD-results from the EQUAL study

BACKGROUND

Chronic kidney disease-mineral and bone disorder (CKD-MBD) is a common complication of CKD; it is associated with higher mortality in dialysis patients, while its impact in non-dialysis patients remains mostly unknown. We investigated the associations between parathyroid hormone (PTH), phosphate and calcium (and their interactions), and all-cause, cardiovascular (CV) and non-CV mortality in older non-dialysis patients with advanced CKD.

METHODS

We used data from the European Quality study, which includes patients aged ≥65 years with estimated glomerular filtration rate ≤20 mL/min/1.73 m2 from six European countries. Sequentially adjusted Cox models were used to assess the association between baseline and time-dependent CKD-MBD biomarkers and all-cause, CV and non-CV mortality. Effect modification between biomarkers was also assessed.

RESULTS

In 1294 patients, the prevalence of CKD-MBD at baseline was 94%. Both PTH [adjusted hazard ratio (aHR) 1.12, 95% confidence interval (CI) 1.03-1.23, P = .01] and phosphate (aHR 1.35, 95% CI 1.00-1.84, P = .05), but not calcium (aHR 1.11, 95% CI 0.57-2.17, P = .76), were associated with all-cause mortality. Calcium was not independently associated with mortality, but modified the effect of phosphate, with the highest mortality risk found in patients with both hypercalcemia and hyperphosphatemia. PTH level was associated with CV mortality, but not with non-CV mortality, whereas phosphate was associated with both CV and non-CV mortality in most models.

CONCLUSIONS

CKD-MBD is very common in older non-dialysis patients with advanced CKD. PTH and phosphate are independently associated with all-cause mortality in this population. While PTH level is only associated with CV mortality, phosphate seems to be associated with both CV and non-CV mortality.

The risk factors and predictive model for cardiac valve calcification in patients on maintenance peritoneal dialysis: a single-center retrospective study

BACKGROUND

Cardiovascular calcification includes cardiac valve calcification (CVC) and vascular calcification. We aimed to analyze risk factors for CVC, and construct a predictive model in maintenance peritoneal dialysis (MPD) patients.

METHODS

We retrospectively analyzed MPD patients who began peritoneal dialysis between January 2014 and September 2021. Patients were randomly assigned to the derivation cohort and validation cohort in a 7:3 ratio. The patients in the derivation cohort were divided into the CVC group and non-CVC group. Logistic regression was used to analyze risk factors, then the rms package in R language was used to construct a nomogram model to predict CVC.

RESULTS

1,035 MPD patients were included, with the age of 50.0 ± 14.2 years and 632 males (61.1%). Their median follow-up time was 25 (12, 46) months. The new-onset CVC occurred in 128 patients (12.4%). In the derivation cohort, multivariate logistic regression indicated old age, female, high systolic blood pressure (SBP), high calcium-phosphorus product (Ca × P), high Charlson comorbidity index (CCI) and long dialysis time were independent risk factors for CVC (p < 0.05). We constructed a nomogram model for predicting CVC in the derivation cohort, with a C index of 0.845 (95% CI 0.803-0.886). This model was validated with a C index of 0.845 (95%CI 0.781-0.909) in the validation cohort.

CONCLUSION

We constructed a nomogram model for CVC in MPD patients, using independent risk factors including age, sex, SBP, Ca × P, CCI and dialysis time. This model achieved high efficiency in CVC prediction.

Paricalcitol and Extended-Release Calcifediol for Treatment of Secondary Hyperparathyroidism in Non-Dialysis Chronic Kidney Disease: Results From a Network Meta-Analysis

CONTEXT

Secondary hyperparathyroidism (SHPT) is a complication of chronic kidney disease (CKD) affecting mineral and bone metabolism and characterized by excessive parathyroid hormone (PTH) production and parathyroid hyperplasia.

OBJECTIVE

The objective of this analysis was to compare the efficacy and adverse effects of extended-release calcifediol (ERC) and paricalcitol (PCT) by assessing their effect on the biomarkers PTH, calcium, and phosphate in patients with non-dialysis CKD (ND-CKD).

METHODS

A systematic literature research was performed in PubMed to identify randomized control trials (RCTs). Quality assessment was done with the GRADE method. The effects of ERC vs PCT were compared using random effects in a frequentist setting.

RESULTS

Nine RCTs comprising 1426 patients were included in the analyses. The analyses were performed on 2 overlapping networks, due to nonreporting of outcomes in some of the included studies. No head-to-head trials were identified. No statistically significant differences in PTH reduction were found between PCT and ERC. Treatment with PCT showed statistically significant increases in calcium compared with ERC (0.2 mg/dL increase; 95% CI, -0.37 to -0.05 mg/dL). No differences in effects on phosphate were observed.

CONCLUSION

This network meta-analysis showed that ERC is comparable in lowering PTH levels vs PCT. ERC displayed avoidance of potentially clinically relevant increases in serum calcium, offering an effective and well-tolerated treatment option for the management of SHPT in patients with ND-CKD.

Novel Approaches in Chronic Renal Failure without Renal Replacement Therapy: A Review

Chronic kidney disease (CKD) is characterized by renal parenchymal damage leading to a reduction in the glomerular filtration rate. The inflammatory response plays a pivotal role in the tissue damage contributing to renal failure. Current therapeutic options encompass dietary control, mineral salt regulation, and management of blood pressure, blood glucose, and fatty acid levels. However, they do not effectively halt the progression of renal damage. This review critically examines novel therapeutic avenues aimed at ameliorating inflammation, mitigating extracellular matrix accumulation, and fostering renal tissue regeneration in the context of CKD. Understanding the mechanisms sustaining a proinflammatory and profibrotic state may offer the potential for targeted pharmacological interventions. This, in turn, could pave the way for combination therapies capable of reversing renal damage in CKD. The non-replacement phase of CKD currently faces a dearth of efficacious therapeutic options. Future directions encompass exploring vaptans as diuretics to inhibit water absorption, investigating antifibrotic agents, antioxidants, and exploring regenerative treatment modalities, such as stem cell therapy and novel probiotics. Moreover, this review identifies pharmaceutical agents capable of mitigating renal parenchymal damage attributed to CKD, targeting molecular-level signaling pathways (TGF-β, Smad, and Nrf2) that predominate in the inflammatory processes of renal fibrogenic cells.

A New Predictive Equation for Estimating Serum Ionized Calcium Levels in Patients on Chronic Hemodialysis

BACKGROUND Circulating calcium mainly carries out its physiologic function in its ionized form (iCa). Clinically, iCa is usually estimated by multiplying the total calcium (TCa) level by 0.5 in the general population, but this method is not accurate when applied to patients on long-term hemodialysis (CHD). Accordingly, this study aimed to develop a predictive function for iCa in patients on CHD by incorporating TCa and other additional variables. MATERIAL AND METHODS This was a retrospective cross-sectional study consisting of 2 cross-sectional datasets: a derivation set including 469 CHD patients in June 2019, and a validation set including 446 CHD patients in September 2019. The derivation set's data were analyzed using the stepwise model selection of machine learning with 10-fold cross-validation to develop a predictive function for iCa. This predictive function was then applied to the validation set's data, and the predictive function's estimated iCa was compared with the actual laboratory iCa by using the paired-samples t test and intraclass correlation coefficient. RESULTS After analyzing the routine laboratory data parameters of patients in the derivation set, the following 5 variables were included in the predictive function of iCa: blood urea nitrogen, creatinine, phosphate, TCa, and albumin. This predictive function was applied to the validation set to yield an estimated iCa level that was not significantly different from the laboratory-measured iCa level of the validation dataset (P=0.676) with an excellent ICC of 0.905. CONCLUSIONS We developed a new predictive function that accurately measures the iCa in patients on CHD by using routine laboratory data.

Automatic Segmentation and Quantification of Abdominal Aortic Calcification in Lateral Lumbar Radiographs Based on Deep-Learning-Based Algorithms

To investigate the performance of deep-learning-based algorithms for the automatic segmentation and quantification of abdominal aortic calcification (AAC) in lateral lumbar radiographs, we retrospectively collected 1359 consecutive lateral lumbar radiographs. The data were randomly divided into model development and hold-out test datasets. The model development dataset was used to develop U-shaped fully convolutional network (U-Net) models to segment the landmarks of vertebrae T12-L5, the aorta, and anterior and posterior aortic calcifications. The AAC lengths were calculated, resulting in an automatic Kauppila score output. The vertebral levels, AAC scores, and AAC severity were obtained from clinical reports and analyzed by an experienced expert (reference standard) and the model. Compared with the reference standard, the U-Net model demonstrated a good performance in predicting the total AAC score in the hold-out test dataset, with a correlation coefficient of 0.97 (p <0.001). The overall accuracy for the AAC severity was 0.77 for the model and 0.74 for the clinical report. Additionally, the Kendall coefficient of concordance of the total AAC score prediction was 0.89 between the model-predicted score and the reference standard, and 0.88 between the structured clinical report and the reference standard. In conclusion, the U-Net-based deep learning approach demonstrated a relatively high model performance in automatically segmenting and quantifying ACC.

THE EFFECT OF PARICALCITOL AND CALCITRIOL WITH OR WITHOUT CALCIMIMETICS ON PULSE WAVE VELOCITY AND SERUM LEVELS FOR PARATHYROID HORMONE, CALCIUM AND PHOSPHORUS IN MAINTENANCE HEMODIALYSIS PATIENTS

Context

Different vitamin D analogs might have advantages over calcitriol.

Objective

To evaluate the effects of paricalcitol vs. calcitriol based vitamin D receptor activators on calcium-phosphate metabolism and pulse wave velocity in hemodialysis patients.

Design

Observational, cross-sectional and 1 year follow-up study.

Subjects and Methods

181 hemodialysis patients were enrolled in this study as divided in to 5 groups based on vitamin D therapy. Baseline and 12th month data on blood biochemistry, pulse wave velocity and cumulative dose of treatments were compared in each study group as well as in overall paricalcitol vs. calcitriol-based treatment groups.

Results

From baseline to 12th month, significant improvement in pulse wave velocity and parathyroid hormone was shown in paricalcitol-based treatment group without a significant change in calcium, phosphate, alkaline phosphatase. A significant increase in pulse wave velocity, serum phosphate levels, calcium x phosphate product and serum alkaline phosphatase levels were noted in calcitriol-based treatment group with no significant change in serum calcium and parathyroid hormone levels.

Conclusion

Our findings revealed superiority of paricalcitol than calcitriol based vitamin D receptor activator therapy in terms of serum phosphate levels, CaxP product, dose requirement for vitamin D and the control of pulse wave velocity.

Efficacy and safety of tenapanor in hemodialysis patients with hyperphosphatemia: A systematic review and meta-analysis of randomized placebo-controlled trials

BACKGROUND

The effects of tenapanor in reducing serum phosphorus in hemodialysis patients with hyperphosphatemia are uncertain and no relevant meta-analysis has been conducted. We performed a meta-analysis of randomized placebo-controlled trials to evaluate the efficacy and safety of tenapanor.

METHODS

All randomized controlled trials of tenapanor were searched up to 1 August 2022. The primary endpoint was the change in serum phosphorus level from baseline with tenapanor and placebo. Data on drug-related adverse events (AEs), gastrointestinal AEs and diarrhea were collected to determine the safety of tenapanor.

RESULTS

There were 533 patients throughout five trials that were eligible. Tenapanor significantly lowered blood phosphorus level by 1.79 mg/dl in the mean difference than the placebo. Diarrhea, gastrointestinal AEs, and drug-related AEs were more severe than placebo.

CONCLUSIONS

This meta-analysis showed that although drug side effects were common, tenapanor significantly reduced serum phosphorus level in hemodialysis patients.

Efficacy and safety of medications for osteoporosis in kidney transplant recipients or patients with chronic kidney disease: A meta-analysis

This study conducted a meta-analysis to analyze the efficacy and safety of osteoporosis medications in kidney transplant recipients and patients with chronic kidney disease (CKD). PubMed, Embase, the Cochrane Central Register of Controlled Trials were searched from the date of their inception through October 21, 2022. We performed a meta-analysis of the efficacy and safety of osteoporosis medications in adult patients with stage 3-5 CKD or kidney transplant recipients enrolled in randomized clinical trials (RCTs). We calculated the standard mean deviations with 95% confidence intervals (CI) for bone mineral density (BMD) and T scores after 6 and 12 months treatment, pooled odds ratio and 95% CI for fracture risk, and summarized adverse events. The inclusion criteria were met by 27 studies. Out of this, 19 studies were included for the meta-analysis. In stage 3-4 CKD patients, alendronate increased lumbar spine BMD. In patients at stage 5 CKD and undergoing hemodialysis, alendronate and raloxifene increased lumbar spine BMD. After 6 months, the BMD of kidney transplant recipients was seen to be significantly increased; however, there was no difference after 12 months, and the risk of fracture did not reduce. Thus, there is no evidence that these medications reduce the risk of fracture, and their effect on BMD and fracture remains unproven. These medications may increase the incidence of adverse events and their safety needs to be further evaluated. Therefore, we cannot draw a definitive conclusion about the efficacy and safety of osteoporosis medications in the above group of patients.

The open system of FGF-23 at the crossroad between additional P-lowering therapy, anemia and inflammation: how to deal with the intact and the C-terminal assays?

Fibroblast growth factor 23 (FGF-23) has been associated with increased cardiovascular risk and poor survival in dialysis patients. It is well established that FGF-23 synthesis is directly induced by positive phosphate (P) balance. On the other hand, P-lowering treatments such as nutritional P restriction, P binders and dialysis are capable of reducing FGF-23 levels. However, there are many uncertainties regarding the possibility of adopting FGF-23 to guide the clinical decision-making process in the context of chronic kidney disease-mineral bone disorder (CKD-MBD). Furthermore, the best assay to adopt for measurement of FGF-23 levels (namely the intact vs the C-terminal one) remains to be determined, especially in conditions capable of altering the synthesis as well as the cleavage of the intact and biologically active molecule, as occurs in the presence of CKD and its complications. This Editorial discusses the main insights provided by the post hoc analysis of the NOPHOS trial, with particular attention given to evidence-based peculiarities of the intact and the C-terminal assays available for measuring FGF-23 levels, especially in patients receiving additive P-lowering therapy in the presence of inflammation, anemia and iron deficiency.

High-resolution peripheral quantitative computed tomography: research or clinical practice?

High-resolution peripheral quantitative CT (HR-pQCT) is a low-dose three-dimensional imaging technique, originally developed for in vivo assessment of bone microarchitecture at the distal radius and tibia in osteoporosis. HR-pQCT has the ability to discriminate trabecular and cortical bone compartments, providing densitometric and structural parameters. At present, HR-pQCT is mostly used in research settings, despite evidence showing that it may be a valuable tool in osteoporosis and other diseases. This review summarizes the main applications of HR-pQCT and addresses the limitations that currently prevent its integration into routine clinical practice. In particular, the focus is on the use of HR-pQCT in primary and secondary osteoporosis, chronic kidney disease (CKD), endocrine disorders affecting bone, and rare diseases. A section on novel potential applications of HR-pQCT is also present, including assessment of rheumatic diseases, knee osteoarthritis, distal radius/scaphoid fractures, vascular calcifications, effect of medications, and skeletal muscle. The reviewed literature seems to suggest that a more widespread implementation of HR-pQCT in clinical practice would offer notable opportunities. For instance, HR-pQCT can improve the prediction of incident fractures beyond areal bone mineral density provided by dual-energy X-ray absorptiometry. In addition, HR-pQCT may be used for the monitoring of anti-osteoporotic therapy or for the assessment of mineral and bone disorder associated with CKD. Nevertheless, several obstacles currently prevent a broader use of HR-pQCT and would need to be targeted, such as the small number of installed machines worldwide, the uncertain cost-effectiveness, the need for improved reproducibility, and the limited availability of reference normative data sets.

Trends in mortality and comorbidities in hemodialysis patients between 2012 and 2017 in an East-European Country: a retrospective study

PURPOSE

The aim of this study was to evidence trends and changes in mortality, comorbid conditions, prognosis, and causes of death after 5 years of continuous evolution of hemodialysis (HD) patients in Romania.

METHODS

We included two cohorts of stable HD patients (901 from 2012 and 1396 from 2017). Both cohorts were followed up for 1 year. The 5-year survivors of the 2012 cohort were identified in 2017 and their data changes were assessed.

RESULTS

The 2017 patients were older, with longer time on dialysis, higher serum creatinine and urea levels, and required higher ultrafiltration volume per dialysis. They also had lower hemoglobin, lower C-reactive protein, higher albumin, higher calcium bicarbonate, and higher parathyroidectomy prevalence. The 2017 cohort presented with lower average dialysis flow, less administration of iron sucrose, had more catheters, lower hepatitis C prevalence, higher diabetes mellitus prevalence, higher heart valve calcifications, higher heart rate disorders, higher prevalence of left ventricular hypertrophy, and lower ejection fraction. Cardiovascular disease was the main cause of death in both years (50% in 2012 and 45.6% in 2017), followed by sepsis and cancer. The mortality was higher in 2017 compared to 2012 (14.1 vs 6.6%). The 5-year mortality was 37.2% with an average of 7.44%/year. The risk of death increased with age, higher C-reactive protein, higher phosphate, lower hemoglobin, and lower albumin.

CONCLUSION

Cardiovascular disease remains the main causes of death in HD-treated patients but with decreasing trend. Developing regional therapeutic strategies for quality care with early intervention will most likely improve mortality.

[Diagnosis and treatment of osteoporosis in patients with chronic kidney disease : Joint guidelines of the Austrian Society for Bone and Mineral Research (ÖGKM), the Austrian Society of Physical and Rehabilitation Medicine (ÖGPMR) and the Austrian Society of Nephrology (ÖGN)]

DEFINITION AND EPIDEMIOLOGY

Chronic kidney disease (CKD): abnormalities of kidney structure or function, present for over 3 months. Staging of CKD is based on GFR and albuminuria (not graded). Osteoporosis: compromised bone strength (low bone mass, disturbance of microarchitecture) predisposing to fracture. By definition, osteoporosis is diagnosed if the bone mineral density T‑score is ≤ -2.5. Furthermore, osteoporosis is diagnosed if a low-trauma (inadequate trauma) fracture occurs, irrespective of the measured T‑score (not graded). The prevalence of osteoporosis, osteoporotic fractures and CKD is increasing worldwide (not graded). PATHOPHYSIOLOGY, DIAGNOSIS AND TREATMENT OF CHRONIC KIDNEY DISEASE-MINERAL AND BONE DISORDER (CKD-MBD): Definition of CKD-MBD: a systemic disorder of mineral and bone metabolism due to CKD manifested by either one or a combination of the following: abnormalities of calcium, phosphorus, PTH, or vitamin D metabolism; renal osteodystrophy; vascular calcification (not graded). Increased, normal or decreased bone turnover can be found in renal osteodystrophy (not graded). Depending on CKD stage, routine monitoring of calcium, phosphorus, alkaline phosphatase, PTH and 25-OH-vitamin D is recommended (2C). Recommendations for treatment of CKD-MBD: Avoid hypercalcemia (1C). In cases of hyperphosphatemia, lower phosphorus towards normal range (2C). Keep PTH within or slightly above normal range (2D). Vitamin D deficiency should be avoided and treated when diagnosed (1C).

DIAGNOSIS AND RISK STRATIFICATION OF OSTEOPOROSIS IN CKD

Densitometry (using dual X‑ray absorptiometry, DXA): low T‑score correlates with increased fracture risk across all stages of CKD (not graded). A decrease of the T‑score by 1 unit approximately doubles the risk for osteoporotic fracture (not graded). A T-score ≥ -2.5 does not exclude osteoporosis (not graded). Bone mineral density of the lumbar spine measured by DXA can be increased and therefore should not be used for the diagnosis or monitoring of osteoporosis in the presence of aortic calcification, osteophytes or vertebral fracture (not graded). FRAX can be used to aid fracture risk estimation in all stages of CKD (1C). Bone turnover markers can be measured in individual cases to monitor treatment (2D). Bone biopsy may be considered in individual cases, especially in patients with CKD G5 (eGFR < 15 ml/min/1.73 m2) or CKD 5D (dialysis).

SPECIFIC TREATMENT OF OSTEOPOROSIS IN PATIENTS WITH CKD

Hypocalcemia should be treated and serum calcium normalized before initiating osteoporosis therapy (1C). CKD G1-G2 (eGFR ≥ 60 ml/min/1.73 m2): treat osteoporosis as recommended for the general population (1A). CKD G3-G5D (eGFR < 60 ml/min/1.73 m2 to dialysis): treat CKD-MBD first before initiating osteoporosis treatment (2C). CKD G3 (eGFR 30-59 ml/min/1.73 m2) with PTH within normal limits and osteoporotic fracture and/or high fracture risk according to FRAX: treat osteoporosis as recommended for the general population (2B). CKD G4-5 (eGFR < 30 ml/min/1.73 m2) with osteoporotic fracture (secondary prevention): Individualized treatment of osteoporosis is recommended (2C). CKD G4-5 (eGFR < 30 ml/min/1.73 m2) and high fracture risk (e.g. FRAX score > 20% for a major osteoporotic fracture or > 5% for hip fracture) but without prevalent osteoporotic fracture (primary prevention): treatment of osteoporosis may be considered and initiated individually (2D). CKD G4-5D (eGFR < 30 ml/min/1.73 m2 to dialysis): Calcium should be measured 1-2 weeks after initiation of antiresorptive therapy (1C).

PHYSICAL MEDICINE AND REHABILITATION

Resistance training prioritizing major muscle groups thrice weekly (1B). Aerobic exercise training for 40 min four times per week (1B). Coordination and balance exercises thrice weekly (1B). Flexibility exercise 3-7 times per week (1B).

Current and Emerging Markers and Tools Used in the Diagnosis and Management of Chronic Kidney Disease-Mineral and Bone Disorder in Non-Dialysis Adult Patients

Chronic kidney disease (CKD) is a significant public health concern associated with significant morbidity and has become one of the foremost global causes of death in recent years. A frequent comorbidity of CKD is secondary hyperparathyroidism (SHPT), exemplified by high serum parathyroid hormone (PTH) levels. The mineral metabolism disturbances resulting from CKD and progression to SHPT are currently considered part of the definition of chronic kidney disease-mineral and bone disorder (CKD-MBD). However, CKD-MBD does not only include abnormalities in laboratory-measured parameters; it is a complex condition characterized by dysregulation of bone turnover, mineralization, growth and strength, accompanied by vascular or another soft-tissue calcification. Together, this increases the risk of bone fractures, cardiovascular disease, and overall mortality in CKD-MBD patients. Monitoring serum markers is essential in diagnosing SHPT and CKD-MBD, and there are several recognized indicators for prognosis, optimal clinical management and treatment response in late-stage kidney disease patients receiving dialysis. However, far fewer markers have been established for patients with non-dialysis CKD. This review provides an overview of current and emerging markers and tools used in the diagnosis and management of CKD-MBD in non-dialysis adult patients.

Pathophysiological concepts and screening of cardiovascular disease in dialysis patients

Dialysis patients experience 10-20 times higher cardiovascular mortality than the general population. The high burden of both conventional and nontraditional risk factors attributable to loss of renal function can explain higher rates of cardiovascular disease (CVD) morbidity and death among dialysis patients. As renal function declines, uremic toxins accumulate in the blood and disrupt cell function, causing cardiovascular damage. Hemodialysis patients have many cardiovascular complications, including sudden cardiac death. Peritoneal dialysis puts dialysis patients with end-stage renal disease at increased risk of CVD complications and emergency hospitalization. The current standard of care in this population is based on observational data, which has a high potential for bias due to the paucity of dedicated randomized clinical trials. Furthermore, guidelines lack specific guidelines for these patients, often inferring them from non-dialysis patient trials. A crucial step in the prevention and treatment of CVD would be to gain better knowledge of the influence of these predisposing risk factors. This review highlights the current evidence regarding the influence of advanced chronic disease on the cardiovascular system in patients undergoing renal dialysis.

Effects of iron-based phosphate binders on mortality and cardiovascular events in patients receiving maintenance dialysis

Phosphate binders are the main treatment for hyperphosphatemia in patients with chronic kidney disease, and iron-based phosphate binders have been used with increasing frequency in recent years. This study examined the association of the use of iron-based, rather than non-iron-based, phosphate binders with the incidence of cardiovascular events, in a real-world setting. We used data from a cohort comprising representative adult patients on maintenance hemodialysis in Japan. The exposure of interest was the time-varying use of phosphate binders, classified into "iron-based", "only non-iron-based", and "no use". The primary outcome was a composite of cardiovascular events and all-cause deaths. A marginal structural Cox regression model was used to deal with possible time-dependent confounding. Of the 2247 patients from 58 hemodialysis facilities, iron-based and only non-iron-based phosphate binders were used in 328 (15%) and 1360 (61%), respectively, at baseline. Hazard ratios (95% confidence intervals) for iron-based and non-iron-based phosphate binders versus no use of phosphate binders were 0.35 (0.24, 0.52) and 0.44 (0.33, 0.58), respectively. The hazard ratio for iron-based relative to non-iron-based phosphate binders was 0.81 (0.58, 1.13), which was not statistically significant. Further studies are warranted to elucidate whether the use of iron-based phosphate binders reduces the event rate.

Misdiagnosis of chronic kidney disease and parathyroid hormone testing during the past 16 years

Chronic kidney disease (CKD) is a prevalent pathological condition worldwide. Parathyroid hormone (PTH) is an important index related to bone metabolism in CKD patients and has not received enough attention. This study was performed to investigate the incidence and diagnostic rate of CKDin hospital as well as PTH testing and treatment for secondary hyperparathyroidism (SHPT) in patients with stage 3 to 5 CKD. The data of patients who visited Zhejiang Provincial People's Hospital from February 2006 to April 2022 were retrieved from the hospital database. All data were divided into three subgroups using PTH testing and SHPT treatment as major comparative indicators for analysis. The data were then analyzed for overall PTH testing, CKD incidence, and diagnostic rate. Among 5,301,391 patients, the incidence of CKD was 13.14%. The missed diagnosis rate for CKD was 65.76%. The total PTH testing rate was 1.22%, of which 15.37% of PTH testing was performed in patients with stage 3 to 5 CKD. The overall diagnosis rate of SHPT in patients with stage 3 to 5 CKD was 31.0%. The prophylactic medication rate was 7.4%, and the rate of post-diagnostic drug therapy was 22.2% in patients who underwent SHPT treatment. The high misdiagnosis rate and low PTH testing rate of CKD requires prompt attention from clinicians. SHPT treatment should be considered especially in patients with stage 3 to 5 CKD.

The relationship between serum pro-B type natriuretic peptide level and bone mineral density in peritoneal dialysis patients

We aimed to evaluate the relationship between serum N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and lumbar bone mineral density (BMD) in peritoneal dialysis (PD) patients. Fasting blood samples were obtained from 46 PD patients. BMD was measured by dual-energy X-ray absorptiometry of the lumbar vertebrae (L1-L4). Circulating serum NT-pro-BNP levels were measured using commercial kits compatible with the Roche Cobas e 601 immunoassay device. Forty-six patients were included in our study. Increased age, low body mass index (BMI), and high-serum NT-pro-BNP are significantly associated with decreased BMD. The results show a statistically positive correlation between lumbar T-score values and BMI (r = 0.456; P = .001), while lumbar T-score values and PTH (rho = -0.336; P = .022) and log-NT-pro-BNP. There is a statistically negative correlation between BNP (rho = -0.355; P = .015). The lumbar T-score value decreases by 0.800 units when log-NT-pro-BNP increases by 1 unit and increases by 0.323 units when BMI increases by 1 unit. The established model is statistically significant (F = 6.190; P < .001). Our study in PD patients showed that serum NT-pro-BNP level was negatively correlated and BMI was positively correlated with lumbar BMD.

The effect of intradialytic exercise on calcium, phosphorus and parathyroid hormone: a randomized controlled trial

BACKGROUND

Patients with kidney failure experience derangements of circulating markers of mineral metabolism and dysregulation of skeletal and cardiovascular physiology which results in high mortality rate in these patients. This study aimed to evaluate the effect of intradialytic exercise on regulation of these abnormalities in patients receiving chronic hemodialysis (HD).

METHODS

In this randomized controlled trial conducted in an HD center in Iran, adult patients receiving chronic HD were randomized to intradialytic exercise (60 min) in the second hour of thrice weekly dialysis for 6 months (intervention) or no intradialytic exercise (control). The primary outcomes were serum calcium, serum phosphorous and parathyroid hormone levels. Secondary outcomes were serum alkaline phosphatase and calcium-phosphorous product.

RESULTS

The study included 44 participants randomized to intervention (n = 22) or control (n = 22). During the 6-month intervention period, significant between-group changes were observed in all primary and secondary outcomes between the intervention and control groups. Statistical analyses reveal a significant increase in serum calcium (P < 0.05) as well as a significant decrease in serum phosphorous, parathyroid hormone, alkaline phosphatase and calcium-phosphorous product (P < 0.05).

CONCLUSION

Intradialytic exercise performed for at least 60 min during thrice weekly dialysis sessions improves bone mineral metabolism in adult patients receiving HD. Further studies should focus on observing and comparing the effect of different types of exercise on bone mineral disorders and all-cause mortality in HD patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04916743, Registered on 08/06/2021. Registered trial name: The Effect of Intradialytic Exercise on Calcium, Phosphorous and Parathyroid Hormone: A Randomized Controlled Trial.

Application of real time shear wave elastography to the differential diagnosis of secondary parathyroid hyperplasia and adenoma

We aimed to explore the value of ultrasonic elastic imaging in the diagnosis of parathyroid hyperplasia and adenoma in patients with secondary hyperparathyroidism and provide more evidence for clinical treatment. Forty patients who were on dialysis and underwent parathyroid surgery were selected All patients underwent routine ultrasound, ultrasound elasticity examination and blood biochemical examination before surgery, including calcium, phosphorus, parathyroid hormone (PTH), etc. According to postoperative results, adenoma group and hyperplasia group were divided into 2 groups. Receiver operating characteristic curve was drawn to evaluate the diagnostic efficacy and combined diagnostic efficacy of each index. The PTH levels significantly differed between the adenoma and hyperplasia groups (P < .001). The volume and blood flow grades significantly differed between the adenoma and hyperplasia groups (P < .001) The minimum of the adenoma group was 14.62 ± 6.79 kPa, mean was 19.42 ± 6.29 kPa, and maximum was 24.25 ± 6.35 kPa which were significantly different from those in the hyperplasia group (P < .05). The combinations of more than 6 indicators in the diagnosis of parathyroid adenoma resulted in an area under the curve of 0.892 (P < .001), and the sensitivity and specificity were 78.9% and 97.4%, respectively. Shear wave elastography can be used as an effective tool to distinguish secondary parathyroid hyperplasia from adenoma. When combined with PTH, conventional ultrasound blood flow grading and volume measurement, it has higher diagnostic efficacy.

Denosumab Use in Chronic Kidney Disease Associated Osteoporosis: A Narrative Review

Chronic kidney disease (CKD) and hemodialysis (HD) patients have a high incidence of bone disease and increased fracture risk, making effective management of their bone health a clinical challenge. Denosumab, a human monoclonal antibody, has been investigated as a therapeutic option in this patient population. In this review, we summarize the current evidence on the efficacy and safety of denosumab in CKD and HD patients. A comprehensive search of the relevant literature was conducted, including randomized controlled trials, observational studies, and meta-analyses. The findings suggest that denosumab reduces the risk of fractures and improves bone mineral density in all stages of CKD. The results of this review support the use of denosumab as a promising option for managing bone disease in CKD and HD patients.

Preptin: A New Bone Metabolic Parameter?

Preptin is a 34-aminoacid peptide derived from the E-peptide of pro-insulin-like growth factor 2 (pro-IGF2) that is co-secreted with insulin and upregulates glucose-mediated insulin secretion. High serum preptin levels were described in conditions associated with insulin resistance, such as polycystic ovary syndrome and type 2 diabetes mellitus (T2M). Insulin and also IGF2 are known to be anabolic bone hormones. The "sweet bone" in T2M usually associates increased density, but altered microarchitecture. Therefore, preptin was proposed to be one of the energy regulatory hormones that positively impacts bone health. Experimental data demonstrate a beneficial impact of preptin upon the osteoblasts. Preptin also appears to regulate osteocalcin secretion, which in turn regulates insulin sensitivity. Preptin is greatly influenced by the glucose tolerance status and the level of physical exercise, both influencing the bone mass. Clinical studies describe low serum preptin concentrations in osteoporosis in both men and women, therefore opening the way towards considering preptin a potential bone anabolic therapy. The current review addresses the relationship between preptin and bone mass and metabolism in the experimental and clinical setting, also considering the effects of preptin on carbohydrate metabolism and the pancreatic-bone loop.

Evaluation of the efficacy and tolerability of alendronate versus denosumab in kidney transplant patients with reduced bone mineral density

PURPOSE

To compare the effect of denosumab and alendronate on bone mineral density (BMD) in renal transplant recipients (RTRs) with low bone mass.

METHODS

Patients were randomized to receive either denosumab subcutaneously (60 mg/6 months), oral alendronate (70 mg/week), or no treatment for 1 year. The three groups were prescribed daily calcium and vitamin D. Primary outcome was BMD assessed at lumbar spine, hip, and radius and measured by dual-energy X-ray absorptiometry (DEXA) at baseline and after 6 and 12 months. Adverse events and laboratory assessments (calcium, phosphate, vitamin D, renal functions, and intact parathyroid hormone) were monitored for all patients. Quality of life was assessed at baseline and after 6 and 12 months for all patients.

RESULTS

Ninety RTRs were included in the study (30 in each group). Baseline clinical characteristics and BMD values were comparable in the three groups. After 12 months, lumbar spine T-score of patients treated with denosumab and alendronate showed a median increase of 0.5 [95% confidence interval (CI): 0.4-0.6] and 0.5 (95% CI: 0.4-0.8), respectively, and patients in the control group showed a decrease of -0.2 (95% CI: -0.3 to -0.1), p < 0.001. Denosumab and alendronate showed a significant comparable gain in T-scores at hip and radius versus a significant decrease in the control group. Adverse events and laboratory values were similar in the three groups. Both treatments resulted in comparable significant improvement in physical functioning, physical role limitations, vitality, and pain scores.

CONCLUSION

Denosumab and alendronate showed comparable efficacy in improving BMD at all measured skeletal sites and were safe and well-tolerated, with no serious adverse effects reported in RTRs with low bone mass. The study was registered on ClinicalTrials.gov, number NCT04169698.

Discrepancies between Cystatin C-Based and Creatinine-Based eGFR

BACKGROUND

Recent guidance suggests clinicians increase use of cystatin C for the estimation of GFR. Discrepant levels of creatinine- versus cystatin C-based eGFR (eGFRcr versus eGFRcys) can occur and might signify inaccurate estimation of GFR using creatinine alone. This study sought to enhance the knowledge of the risk factors and clinical implications of having a large eGFR discrepancy.

METHODS

Participants in the Atherosclerosis Risk in Communities Study, a prospective cohort study of US adults, were followed over 25 years. eGFR discrepancy was measured at five clinical visits and defined as eGFRcys either 30% lower or higher than eGFRcr, the current clinical standard of care. The associations between eGFR discrepancies and kidney-related laboratory parameters were assessed using linear and logistic regression and long-term adverse outcomes, including kidney failure, AKI, heart failure, and death, using Cox proportional hazards models.

RESULTS

Among 13,197 individuals (mean age 57 [SD 6] years, 56% women, 25% Black race), 7% had eGFRcys 30% lower than eGFRcr at visit 2 (1990-1992), and this proportion increased over time to 23% by visit 6 (2016-2017). By contrast, the percent with eGFRcys 30% higher than eGFRcr was relatively stable (3%-1%). Independent risk factors for having eGFRcys 30% lower than eGFRcr included older age, female sex, non-Black race, higher eGFRcr, higher body mass index, weight loss, and current smoking. Those with eGFRcys 30% lower than eGFRcr had more anemia and higher uric acid, fibroblast growth factor 23, and phosphate levels as well as higher risk of subsequent mortality, kidney failure, AKI, and heart failure compared with those with similar eGFRcr and eGFRcys values.

CONCLUSIONS

Having eGFRcys lower than eGFRcr was associated with worse kidney-related laboratory derangements and a higher risk of adverse health outcomes.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_09_08_CJN0000000000000217.mp3.

Randomized Controlled Clinical Trial of the Effect of Treatment with Vitamin K2 on Vascular Calcification in Hemodialysis Patients (Trevasc-HDK)

Introduction

Vitamin K deficiency among patients on hemodialysis (HD) affects the function of matrix GLA protein (MGP), a potent vitamin K-dependent inhibitor of vascular calcification (VC).

Methods

We conducted a single-center randomized controlled trial (RCT) on maintenance HD patients to examine if vitamin K2 supplementation can reduce progression of coronary artery calcification (CAC) over an 18-month study period. Patients were randomized to vitamin K2 group receiving menaquinone-7360 μg 3 times/wk or control group. The primary outcome was CAC scores at the end of the study period. The secondary outcomes were aortic valve calcification (AVC), carotid-femoral pulse wave velocity (cfPWV), aortic augmentation index (AIx), dephosphorylated undercarboxylated MGP (dp-ucMGP) levels, major adverse cardiac events (MACE), and vascular access events.

Results

Of the 178 patients randomized, follow-up was completed for 138 patients. The CAC scores between the 2 groups were not statistically different at the end of 18 months (relative mean difference [RMD] 0.85, 95% CI 0.55-1.31). The secondary outcomes did not differ significantly in AVC (RMD 0.82, 95% CI 0.34-1.98), cfPWV (absolute mean difference [AMD] 0.55, 95% CI -0.50 to 1.60), and AIx (AMD 0.13, 95% CI -3.55 to 3.80). Supplementation with vitamin K2 did reduce dp-ucMGP levels (AMD -86, 95% CI -854 to -117). The composite outcome of MACE and mortality was not statistically different between the 2 groups (Hazard ratio = 0.98, 95% CI 0.50-1.94).

Conclusion

Our study did not demonstrate a beneficial effect of vitamin K2 in reducing progression of VC in this population at the studied dose and duration.

Resolution of Secondary Hyperparathyroidism After Kidney Transplantation and the Effect on Graft Survival

OBJECTIVE

Hyperparathyroidism (HPT) is nearly universal in patients with end-stage kidney disease. Kidney transplantation (KT) reverses HPT in many patients, but most studies have only focused on following calcium and not parathyroid hormone (PTH) levels. We sought to study the prevalence of persistent HPT post-KT at our center and its effect on graft survival.

METHODS

Patients who underwent KT from January 2015 to August 2021 were included and characterized by post-KT HPT status at the most recent follow-up: resolved (achieving normal PTH post-KT) versus persistent HPT. Those with persistent HPT were further stratified by the occurrence of hypercalcemia (normocalcemic versus hypercalcemic HPT). Patient demographics, donor kidney quality, PTH and calcium levels, and allograft function were compared between groups. Multivariable logistic regression and Cox regression with propensity score matching were conducted.

RESULTS

Of 1554 patients, only 390 (25.1%) patients had resolution of renal HPT post-KT with a mean (±SD) follow-up length of 40±23 months. The median (IQR) length of HPT resolution was 5 (0-16) months. Of the remaining 1164 patients with persistent HPT post-KT, 806 (69.2%) patients had high PTH and normal calcium levels, while 358 (30.8%) patients had high calcium and high PTH levels. Patients with persistent HPT had higher parathyroid hormone (PTH) at the time of KT [403 (243-659) versus 277 (163-454) pg/mL, P <0.001] and were more likely to have received cinacalcet treatment before KT (34.9% vs. 12.3%, P <0.001). Only 6.3% of patients with persistent HPT received parathyroidectomy. Multivariable logistic regression showed race, cinacalcet use pre-KT, dialysis before KT, receiving an organ from a deceased donor, high PTH, and calcium levels at KT were associated with persistent HPT post-KT. After adjusting for patient demographics and donor kidney quality by propensity score matching, persistent HPT (HR 2.5, 95% CI 1.1-5.7, P =0.033) was associated with a higher risk of allograft failure. Sub-analysis showed that both hypercalcemic HPT (HR 2.6, 95% CI 1.1-6.5, P =0.045) and normocalcemic HPT (HR 2.5, 95% CI 1.3-5.5, P =0.021) were associated with increased risk of allograft failure when compared with patients with resolved HPT.

CONCLUSION

Persistent HPT is common (75%) after KT and is associated with a higher risk of allograft failure. PTH levels should be closely monitored after kidney transplantation so that patients with persistent HPT can be treated appropriately.

Advance care planning in chronic kidney disease: A national Danish survey of knowledge and attitudes among clinicians

INTRODUCTION

Patients with chronic kidney disease and their families strongly request advance care planning. They want it to start early-before treatment decisions are made-and to be an ongoing process during their illness trajectory. Previous international studies show that health care professionals find there to be significant barriers that impact the extent of involvement in advance care planning.

AIM

To identify Danish nephrology health care professionals' knowledge and attitudes to advance care planning and the status of current advance care planning practice in Denmark.

METHOD

An anonymous, cross-sectional survey was administrated online. The questionnaire was developed in Australia and translated and culturally adapted into Danish. Health care professionals were recruited via email lists. In descriptive statistics and multiple ordinal regression, the influence of the respondents' attributes on the extent of involvement in advance care planning was explored, along with the involvement of family, and skills, comfort, barriers and facilitators in relation to advance care planning.

RESULTS

The 207 respondents comprised nephrologists (23%), other physicians (8%), nurses (62%) and other HCPs (7%), of whom 27% had participated in advance care planning training. In total, 66% indicated that they lacked access to material about advance care planning for patients with chronic kidney disease and 46% indicated that the conversations were performed ad hoc. A total of 47% reported that advance care planning was performed well at their workplace. Reported barriers were time, lack of experience and procedure. Training in advance care planning could facilitate the involvement. Nurses were less likely to feel skilled and comfortable in engaging advance care planning, while those with more than 10 years of experience were more likely to feel skilled and comfortable.

CONCLUSION

Training in advance care planning with patients with chronic kidney disease and their families on both a theoretical and clinical level is important to ensure comfort among health care professionals and to facilitate the extent of involvement. A systematic chronic kidney disease-specific approach is significant, in order to guide the conversations and ensure that advance care planning is conducted to a set standard.

Association between sclerostin levels and vascular outcomes in kidney transplantation patients

BACKGROUND

The impact of circulating sclerostin levels on vascular calcification has shown conflicting results depending on the target population and vascular anatomy. This study investigated the associations of sclerostin levels with vascular outcomes in kidney transplant patients.

METHODS

In a prospective observational study of the Korean Cohort Study for Outcome in Patients with Kidney Transplantation, 591 patients with serum sclerostin level data prior to transplantation were analyzed. The main predictor was the pre-transplant sclerostin level. Vascular outcomes were the abdominal aortic calcification score and brachial-ankle pulse wave velocity measured at pre-transplant screening and three and five years after kidney transplantation.

RESULTS

In linear regression analysis, sclerostin level positively correlated with changes in abdominal aortic calcification score between baseline and five years after kidney transplantation (coefficient of 0.73 [95% CI, 0.11-1.35] and 0.74 [95% CI, 0.06-1.42] for second and third tertiles, respectively, vs the first tertile). In a longitudinal analysis over five years, using generalized estimating equations, the coefficient of the interaction (sclerostin × time) was significant with a positive value, indicating that higher sclerostin levels were associated with faster increase in post-transplant abdominal aortic calcification score. Linear regression analysis revealed a positive association between pre-transplant sclerostin levels and changes in brachial-ankle pulse wave velocity (coefficient of 126.7 [95% CI, 35.6-217.8], third vs first tertile). Moreover, a significant interaction was identified between sclerostin levels and brachial-ankle pulse wave velocity at five years.

CONCLUSIONS

Elevated pre-transplant sclerostin levels are associated with the progression of post-transplant aortic calcifications and arterial stiffness.

Sex differences in the association between vitamin D and early-stage chronic kidney disease: A population-based study

Vitamin D deficiency (VDD) is commonly observed in people with late-stage chronic kidney disease (CKD) and end-stage renal disease; it has also been associated with the progression of kidney disease. We hypothesized that VDD played a role in early-stage chronic kidney disease as well. Thus, this cross-sectional study aimed to evaluate the association between serum 25-hydroxyvitamin D concentration and CKD stages 1 through 3 (early-stage CKD) in a relatively healthy population in China. A total of 3142 Chinese individuals were included in this cross-sectional study. VDD was observed in 108 (5.6%) males and 307 (25.33%) females. We found a significant inverse association between serum 25(OH)D concentration with CKD stages in both sexes. Furthermore, VDD was associated with CKD stages 1 through 3 in males (adjusted odds ratio, 15.84; 95% confidence interval, 7.85-31.98; P < .001), but not in females. Vitamin D status should be evaluated in people who are newly diagnosed with CKD stages 1 through 3 or decreased estimated glomerular filtration rate, especially in males.