The DOPPS Practice Monitor for US Dialysis Care: PTH Levels and Management of Mineral and Bone Disorder in US Hemodialysis Patients

Comparative Effectiveness of Alternative Treatment Approaches to Secondary Hyperparathyroidism in Patients Receiving Maintenance Hemodialysis: An Observational Trial Emulation

RATIONALE & OBJECTIVE

Optimal approaches to treat secondary hyperparathyroidism (SHPT) in patients on maintenance hemodialysis (HD) have yet to be established in randomized controlled trials (RCTs).

STUDY DESIGN

Two observational clinical trial emulations.

SETTING & PARTICIPANTS

Both emulations included adults receiving in-center HD from a national dialysis organization. The patients who had SHPT in the period between 2009 and 2014, were insured for≥180 days by Medicare as primary payer, and did not have contraindications or poor health status limiting theoretical trial participation.

EXPOSURE

The parathyroid hormone (PTH) Target Trial emulation included patients with new-onset SHPT (first PTH 300-600pg/mL), with 2 arms defined as up-titration of either vitamin D sterols or cinacalcet within 30 days (lower target) or no up-titration (higher target). The Agent Trial emulation included patients with a PTH≥300 pg/mL while on≥6μg weekly of vitamin D sterol (paricalcitol equivalent dose) and no prior history of cinacalcet. The 2 arms were defined by the first dose or agent change within 30 days (vitamin D-favoring [vitamin-D was up-titrated] vs cinacalcet-favoring [cinacalcet was added] vs nondefined [neither applies]). Multiple trials per patient were allowed in trial 2.

OUTCOME

The primary outcome was all-cause death over 24 months; secondary outcomes included cardiovascular (CV) hospitalization or the composite of CV hospitalization or death.

ANALYTICAL APPROACH

Pooled logistic regression.

RESULTS

There were 1,152 patients in the PTH Target Trial (635 lower target and 517 higher target). There were 2,726 unique patients with 6,727 patient trials in the Agent Trial (6,268 vitamin D-favoring trials and 459 cinacalcet-favoring trials). The lower PTH target approach was associated with reduced adjusted hazard of death (HR, 0.71 [95% CI, 0.52-0.93]), CV hospitalization (HR, 0.78 [95% CI, 0.63-0.98]), and their composite (HR, 0.74 [95% CI, 0.61-0.89]). The cinacalcet-favoring approach demonstrated lower adjusted hazard of death compared to the vitamin D-favoring approach (HR, 0.79 [95% CI, 0.62-0.99]), but not of CV hospitalization or the composite outcome.

LIMITATIONS

Potential for residual confounding; low use of cinacalcet with low power.

CONCLUSIONS

SHPT management that is focused on lower PTH targets may lower mortality and CV disease in patients receiving HD. These findings should be confirmed in a pragmatic randomized trial.

PLAIN-LANGUAGE SUMMARY

Optimal approaches to treat secondary hyperparathyroidism (SHPT) have not been established in randomized controlled trials. Data from a national dialysis organization was used to identify patients with SHPT in whom escalated treatment may be indicated. The approach to treatment was defined based on observed upward titration of SHPT-controlling medications: earlier titration (lower target) versus delayed titration (higher target); and the choice of medication (cinacalcet vs vitamin D sterols). In the first trial emulation, we estimated a 29% lower rate of death and 26% lower rate of cardiovascular disease or death for patients managed with a lower versus higher target approach. Cinacalcet versus vitamin D-favoring approaches were not consistently associated with outcomes in the second trial emulation. This observational study suggests the need for additional clinical trials of SHPT treatment intensity.

[Evolution of the incidence and results at 12 months of parathyroidectomy: 40 years of experience in a dialysis center with two successive surgical departments]

INTRODUCTION

Secondary hyperparathyroidism remains the main complication of mineral and bone metabolism in patients with chronic kidney disease. In case of resistance to medical treatment (native and active vitamin D, calcium and calcimimetics), surgical parathyroidectomy is indicated. The aim of this retrospective study is to show the evolution of the incidence and results of surgical parathyroidectomy in our center between 1980 and 2020 as patient characteristics, diagnostic and therapeutic strategies have changed.

PATIENTS AND METHODS

We collected data from dialysis patients who had a first surgical parathyroidectomy between 2000 and 2020 (period 2) in the same surgical department and compared them with historical data between 1980 and 1999 (period 1) operated in one other center.

RESULTS

In period 1, 53 surgical parathyroidectomy were performed (2.78/year, 0 to 5, 8.5/1000 patients-year) vs.56 surgical parathyroidectomy in period 2 (2.8/year, 0 to 9, 8/1000 patients-year). The patients of the 2 periods were comparable except for the higher dialysis vintage in period 1 (149±170 vs.89±94 months; P=0.02). In comparison with dialysis patients not requiring surgical parathyroidectomy during the same period, patients who had surgical parathyroidectomy were younger, had higher dialysis vintage and lower diabetes prevalence, but more frequently carriers of glomerulopathy or polycystosis. Systematically performed in period 2, cervical ultrasound identified at least one visible gland in 78.6% of cases while the scintigraphy, performed only in 66% of cases, found at least one gland in 81% of cases. Twelve months after surgery, PTH > 300 pg/mL (marker of secondary hyperparathyroidism recurrence or surgery failure) was present in 30% of patients in period 1 vs. 5.3% in period 2. Hypoparathyroidism was also more frequently observed in period 2 (35.7 vs. 18.8%). Surgical complications were also higher in period 1.

CONCLUSION

Despite therapeutic and strategic advances, severe secondary hyperparathyroidism is still as common as ever. It is favored by excessively high PTH targets, by suboptimal prevention before dialysis and poor tolerance of calcimimetics. The surgical parathyroidectomy is effective and safe in the hands of a specialized team with an ultrasound and scintigraphic preoperative assessment.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Secondary and Tertiary Renal Hyperparathyroidism

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate treatment of secondary (SHPT) and tertiary (THPT) renal hyperparathyroidism.

BACKGROUND

Hyperparathyroidism is common among patients with chronic kidney disease, end-stage kidney disease, and kidney transplant. The surgical management of SHPT and THPT is nuanced and requires a multidisciplinary approach. There are currently no clinical practice guidelines that address the surgical treatment of SHPT and THPT.

METHODS

Medical literature was reviewed from January 1, 1985 to present January 1, 2021 by a panel of 10 experts in SHPT and THPT. Recommendations using the best available evidence was constructed. The American College of Physicians grading system was used to determine levels of evidence. Recommendations were discussed to consensus. The American Association of Endocrine Surgeons membership reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines present the epidemiology and pathophysiology of SHPT and THPT and provide recommendations for work-up and management of SHPT and THPT for all involved clinicians. It outlines the preoperative, intraoperative, and postoperative management of SHPT and THPT, as well as related definitions, operative techniques, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Preoperative and Perioperative Care, Surgical Planning and Parathyroidectomy, Adjuncts and Approaches, Outcomes, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal management of secondary and tertiary renal hyperparathyroidism.

Effect of High Dose Active Vitamin D Therapy on the Development of Hypocalcemia After Subtotal Parathyroidectomy in Patients on Chronic Dialysis

Background

The period after parathyroidectomy (PTx) in dialysis patients is characterized by periods of severe hypocalcemia. This study aims to investigate the effect of high doses of active vitamin D immediately after PTx on the development of hypocalcemia.

Materials and Methods

We retrospectively reviewed 111 patients with secondary hyperparathyroidism receiving subtotal PTx between 2010 and 2019. A high dose group “HDG” (n = 67) receiving 12 µg alfacalcidol in combination with 8.550 mg calcium acetate per day, which was then adapted according to lab values, was compared with a low dose group “LDG” (n = 44) receiving up to 4 µg alfacalcidol per day. The laboratory values were recorded up to ten weeks postoperatively.

Results

The assumed drops in parathyroid hormone (PTH) and calcium were observed in both groups after PTx. We observed significantly lower calcium values in the LDG between days 4 and 18 postoperatively than in the HDG (p < 0.001). The proportion of severe hypocalcemia after PTx (total calcium <1.5 mmol/l) in the HDG was 8.5% on day 1 and 47% on day 4 in the LDG. Intravenous calcium requirements were significantly lower in the HDG (7.6%) than in the LDG (45.7%; p = 0.001).

Conclusion

The period after PTx in dialysis patients is characterized by an expected drop in PTH and calcium within the first days. Ongoing high turnover is observed in the 2nd and 3rd week after PTx. Administering high doses of alfacalcidol combined with calcium acetate diminishes the episodes of severe hypocalcemia and the need for intravenous calcium.

Outcomes following parathyroidectomy for secondary hyperparathyroidism in patients with chronic kidney disease - a single-centre study

BACKGROUND

Surgical parathyroidectomy may be required for severe and refractory secondary hyperparathyroidism (SHPT) in patients with chronic kidney disease (CKD). Parathyroidectomy is associated with long-term survival benefit despite an increase in short-term morbidity and mortality. Global variation in practice exists, with limited Australian data on outcomes following parathyroidectomy.

METHODS

We conducted a retrospective study of patients who underwent parathyroidectomy for SHPT between January 2010 and December 2019 at a single tertiary referral centre in Melbourne, Australia. Biochemical markers and medications were assessed 12 months pre- and post-surgery. Clinical outcomes, including hospital readmission, cardiovascular events and mortality were assessed following surgery.

RESULTS

During the 10-year study period, 129 patients underwent parathyroidectomy for SHPT (mean age 50.7 ± 15 years, 109 (85%) on dialysis). Significant immediate post-operative complications were seen in eight patients (6%), requiring admission to the intensive care unit (n = 6) or return to theatre (n = 2). Within the first 6 months, 24 patients (19%) required hospital readmission. Within 12 months post-parathyroidectomy, 100 (78%) and 103 patients (80%) experienced at least one episode of hypercalcaemia (corrected calcium >2.6 mmol/L) or hypocalcaemia (corrected calcium <2.1 mmol/L) respectively. Over a 12-month period there were six deaths (5%), and eight patients (6%) experienced a major cardiovascular event.

CONCLUSION

Significant fluctuations in serum calcium levels are common post-parathyroidectomy, however long-term morbidity and mortality in our cohort were lower than previously reported, highlighting that parathyroidectomy in a carefully selected cohort is safe for severe SHPT refractory to medical treatment. This article is protected by copyright. All rights reserved.

Longitudinal Bone Loss Occurs at the Radius in CKD

Introduction

Chronic kidney disease (CKD) exposes to an increased incidence of fragility fractures. International guidelines recommend performing bone mineral density (BMD) if the results will impact treatment decisions. It remains unknown where bone loss occurs and what would preclude the longitudinal loss in patients with CKD. Here, we aimed to investigate factors influencing BMD and to analyze the longitudinal BMD changes.

Methods

In the NephroTest cohort, we measured BMD at the femoral neck, total hip, lumbar spine, and proximal radius, together with circulating biomarkers and standardized measured glomerular filtration rate (mGFR) by ⁵¹Cr-EDTA in a subset of patients with CKD stage 1 to 5 followed during 4.3 ± 2.0 years. A linear mixed model explored the longitudinal bone loss and the relationship of associated factors with BMD changes. A total of 858 patients (mean age 58.9 ± 15.2 years) had at least 1 and 477 had at least 2 BMD measures.

Results

At baseline, cross-sectional analysis showed a significantly lower BMD at femoral neck and total hip and a significant higher serum parathyroid hormone (PTH) along with CKD stages. Baseline age, gender, tobacco, low body mass index (BMI), and high PTH levels were significantly associated with low BMD. Longitudinal analysis during the mean 4.3 years revealed a significant bone loss at the radius only. BMD changes at the femoral neck were associated with BMI, but not CKD stages or basal PTH levels.

Conclusions

CKD is associated with low BMD and high PTH in the cross-sectional analysis. Longitudinal bone loss occurred at the proximal radius after 4.3 years.

Parathyroid Hormone Serum Levels and Mortality among Hemodialysis Patients in the Gulf Cooperation Council Countries: Results from the DOPPS (2012-2018)

BACKGROUND

The prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) has collected data since 2012 in all six Gulf Cooperation Council (GCC) countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and United Arab Emirates). We report the relationship of PTH with mortality in this largest GCC cohort of patients on hemodialysis studied to date.

METHODS

Data were from randomly selected national samples of hemodialysis facilities in GCC-DOPPS phases 5 and 6 (2012-2018). PTH descriptive findings and case mix-adjusted PTH/mortality Cox regression analyses were based on 1825 and 1422 randomly selected patients on hemodialysis, respectively.

RESULTS

Mean patient age was 55 years (median dialysis vintage, 2.1 years). Median PTH ranged from 259 pg/ml (UAE) to 437 pg/ml (Kuwait), with 22% having PTH <150 pg/ml, 24% with PTH of 150-300 pg/ml, 34% with PTH 301-700 pg/ml, and 20% with PTH >700 pg/ml. Patients with PTH >700 pg/ml were younger; on dialysis longer; less likely to be diabetic; have urine >200 ml/d; be prescribed 3.5 mEq/L dialysate calcium; had higher mean serum creatinine and phosphate levels; lower white blood cell counts; and more likely to be prescribed cinacalcet, phosphate binders, or IV vitamin D. A U-shaped PTH/mortality relationship was observed with more than two- and 1.5-fold higher adjusted HR of death at PTH >700 pg/ml and <300 pg/ml, respectively, compared with PTH of 301-450 pg/ml.

CONCLUSIONS

Secondary hyperparathyroidism is highly prevalent among GCC patients on hemodialysis, with a strong U-shaped PTH/mortality relationship seen at PTH <300 and >450 pg/ml. Future studies are encouraged for further understanding this PTH/mortality pattern in relationship to unique aspects of the GCC hemodialysis population.

Parathyroid Hormone Serum Levels and Mortality among Hemodialysis Patients in the Gulf Cooperation Council Countries: Results from the DOPPS (2012–2018)

Background

The prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) has collected data since 2012 in all six Gulf Cooperation Council (GCC) countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and United Arab Emirates). We report the relationship of PTH with mortality in this largest GCC cohort of patients on hemodialysis studied to date.

Methods

Data were from randomly selected national samples of hemodialysis facilities in GCC-DOPPS phases 5 and 6 (2012–2018). PTH descriptive findings and case mix–adjusted PTH/mortality Cox regression analyses were based on 1825 and 1422 randomly selected patients on hemodialysis, respectively.

Results

Mean patient age was 55 years (median dialysis vintage, 2.1 years). Median PTH ranged from 259 pg/ml (UAE) to 437 pg/ml (Kuwait), with 22% having PTH <150 pg/ml, 24% with PTH of 150–300 pg/ml, 34% with PTH 301–700 pg/ml, and 20% with PTH >700 pg/ml. Patients with PTH >700 pg/ml were younger; on dialysis longer; less likely to be diabetic; have urine >200 ml/d; be prescribed 3.5 mEq/L dialysate calcium; had higher mean serum creatinine and phosphate levels; lower white blood cell counts; and more likely to be prescribed cinacalcet, phosphate binders, or IV vitamin D. A U-shaped PTH/mortality relationship was observed with more than two- and 1.5-fold higher adjusted HR of death at PTH >700 pg/ml and <300 pg/ml, respectively, compared with PTH of 301–450 pg/ml.

Conclusions

Secondary hyperparathyroidism is highly prevalent among GCC patients on hemodialysis, with a strong U-shaped PTH/mortality relationship seen at PTH <300 and >450 pg/ml. Future studies are encouraged for further understanding this PTH/mortality pattern in relationship to unique aspects of the GCC hemodialysis population.

Bundled Payment Reform and Dialysis Facility Closures in ESKD

BACKGROUND

In 2011, inclusion of injectable medications into an expanded ESKD payment bundle prompted concerns that dialysis facilities facing higher costs might close, disrupting care delivery and access to care. Whether this policy change influenced dialysis facility closures is unknown.

METHODS

To examine whether facility closures increased after 2011 and whether factors influencing closures changed, we analyzed US Renal Data System registry data to identify all patients receiving in-center hemodialysis from 2006 through 2015 and to track dialysis facility closures. We used interrupted time series logistic regression models and estimated marginal effects to examine immediate and longer-term changes in the likelihood of being affected by facility closures following payment reform. We also examined whether associations between selected predictors of closures indicating populations at "high risk" of closure (patient characteristics, facility characteristics, and geography-related characteristics) and closures changed after payment reform.

RESULTS

Dialysis facility closures were uncommon over the study period. In adjusted models, the relative odds of experiencing a closure declined by 37% (odds ratio [OR], 0.63; 95% confidence interval [95% CI], 0.59 to 0.67) immediately after payment reform and declined by an additional 6% (OR, 0.94; 95% CI, 0.91 to 0.97) annually thereafter, corresponding to a 0.3% lower absolute probability of closure in 2015 in association with payment reform. Patients who were black and who dialyzed at small, hospital-based facilities experienced slight increases in closures following payment reform, whereas Hispanic and Medicare/Medicaid dual-eligible patients experienced slight decreases in closures.

CONCLUSIONS

Expansion of the ESKD payment bundle was not associated with increased closure of dialysis facilities, although the likelihood of closures changed slightly for some higher-risk populations.

New scenarios in secondary hyperparathyroidism: etelcalcetide. Position paper of working group on CKD-MBD of the Italian Society of Nephrology

Bone mineral abnormalities (defined as Chronic Kidney Disease Mineral Bone Disorder; CKD-MBD) are prevalent and associated with a substantial risk burden and poor prognosis in CKD population. Several lines of evidence support the notion that a large proportion of patients receiving maintenance dialysis experience a suboptimal biochemical control of CKD-MBD. Although no study has ever demonstrated conclusively that CKD-MBD control is associated with improved survival, an expanding therapeutic armamentarium is available to correct bone mineral abnormalities. In this position paper of Lombardy Nephrologists, a summary of the state of art of CKD-MBD as well as a summary of the unmet clinical needs will be provided. Furthermore, this position paper will focus on the potential and drawbacks of a new injectable calcimimetic, etelcalcetide, a drug available in Italy since few months ago.

International and Racial Differences in Mineral and Bone Disorder Markers and Treatments Over the First 5 Years of Hemodialysis in the Dialysis Outcomes and Practice Patterns Study

RATIONALE & OBJECTIVE

Normalization of parathyroid hormone (PTH), serum calcium, and phosphorus levels may prevent coronary and bone disease in hemodialysis (HD) patients. We describe the trajectory of these mineral bone disorder parameters and treatments during the first 5 years of HD by international region and race.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

33,517 US black/African American, US non-black/African American, European, and Japanese HD patients from the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases 4 to 5 (2009-2015).

PREDICTOR

Time since HD initiation.

OUTCOMES

Monthly cross-sections of mineral bone disorder parameters (PTH, serum calcium, and phosphorus) and medications (cinacalcet, active vitamin D, and phosphate binders).

RESULTS

Mean PTH levels declined precipitously during the first 4 months of HD in all 4 groups, then steadily increased during the next 4.5 years in the United States/Europe but not in Japan. 3 years after HD initiation (month 36), mean PTH level was highest in US black/African Americans (496 pg/mL), despite greater prescription of cinacalcet (23%) and active vitamin D (85%), and lowest in Japan (151 pg/mL). Mean serum calcium and phosphorus levels increased during the first 4 months of HD. By month 36, the mean calcium level was lower in Japan (8.8 mg/dL) than United States/Europe (9.0-9.1 mg/dL), while the mean phosphorus level was lower in Europe (4.8 mg/dL) than United States/Japan (5.1-5.3 mg/dL).

LIMITATIONS

Lack of data for medication dosages; most patients were not followed from HD onset.

CONCLUSIONS

Large differences exist in the levels, trajectories, and therapies for PTH, calcium, and phosphorus by country and race in the first 5 years of HD. Higher PTH levels were observed in the United States, especially among black/African American patients, despite greater use of cinacalcet and active vitamin D than in Japan or Europe. Potential contributors to differences in PTH levels should be explored to study their impact on PTH management strategies and consequent bone and cardiovascular complications.

Active Vitamin D in Chronic Kidney Disease: Getting Right Back Where We Started from?

Background

The vitamin D system is essential for optimal health in humans. Circulating calcitriol, a key metabolite in maintaining calcium and phosphorus homeostasis, is produced in the kidney. In kidney failure, calcitriol levels progressively decrease, contributing to the development of renal secondary hyperparathyroidism (SHPT).

Summary

For years, SHPT had a central role in the disturbed mineral metabolism of renal patients. As calcitriol deficiency contributes to SHPT development, treatment with calcitriol or other compounds able to activate the vitamin D receptor (VDR) was one of the mainstays of therapy for renal patients in the last 40 years. In this review, we discuss how the treatment with VDR activators (VDRA) evolved during this time in the United States, as well as the main factors responsible for these changes.

Key Messages

Management of SHPT with VDRA in renal patients has undergone a few paradigm shifts over the last 40 years. When treating SHPT, the newly developed therapies as well as VDRA need to be carefully considered and used appropriately. Nephrologists need to use an integrated approach that avoids excessive use of VDRA, ensures replenishment of vitamin D stores, and avoids hypercalcemia and hyperphosphatemia.

Variations and characteristics of quality indicators for maintenance hemodialysis patients: A systematic review

AIMS

Several quality indicators (QIs) to improve the quality of practice for hemodialysis patients have been implemented. However, the variations and characteristics of these indicators in terms of their use and feasibility have not been investigated. We conducted a systematic review to evaluate the variations and characteristics of existing QIs for maintenance hemodialysis patients.

METHODS

We conducted a systematic literature search of MEDLINE via PubMed, Scopus, the Cochrane Library, and CINAHL, without date limits, on February 26, 2016. We selected the English-written articles regarding QIs for patients aged ≥18 years who were on maintenance hemodialysis therapy ≥3 months, and extracted the definition and development process of the reported QIs. We categorized each indicator into one of four types, namely, structure, process, surrogate outcome, and outcome, and assessed the data sources that were necessary to measure it.

RESULTS

We included 70 articles and identified 101 indicators, and found that most of the consensus processes for selecting indicators were unclear. We also found that most indicators were not process indicators and that the measurement of some indicators required a chart review, which limits their use and feasibility.

CONCLUSIONS

Development of QIs for hemodialysis patients in the future should use a definitive consensus process and consider process-centered indicators that can be measured automatically using claims data and test results contained in electronic medical records, to improve usability and feasibility.

The Role of Big Data in the Development and Evaluation of US Dialysis Care

Rapid growth in electronic communications and digitalization, combined with advances in data management, analysis, and storage, have led to an era of "Big Data." The Social Security Amendments of 1972 turned end-stage renal disease (ESRD) care into a single-payer system for most patients requiring dialysis in the United States. As a result, there are few areas of medicine that have been as influenced by Big Data as dialysis care, for which Medicare's large administrative data sets have had a central role in the evaluation and development of public policy for several decades. In the 1970/1980s, Medicare data helped identify concerning trends in costs, access to dialysis care, and quality of care delivered. As the research community and policymakers made Medicare's administrative data increasingly accessible for investigation, analyses of Medicare claims have had a large role in facilitating policy synthesis and refinement. Efforts to address the skyrocketing cost of injectable drugs in the 1990s and 2000s exemplify this expanded role of Big Data. Although there are opportunities for large government and nongovernmental administrative data sets to continue serving a critical role in the evaluation and development of ESRD policies, it is important to understand challenges and limitations associated with their use.

Association of Medicare's Bundled Payment Reform With Changes in Use of Vitamin D Among Patients Receiving Maintenance Hemodialysis: An Interrupted Time-Series Analysis

BACKGROUND & RATIONALE

Medicare's 2011 prospective payment system (PPS) was introduced to curb overuse of separately billable injectable drugs. After epoietin, intravenous (IV) vitamin D analogues are the biggest drug cost drivers in hemodialysis (HD) patients, but the association between PPS introduction and vitamin D therapy has been scarcely investigated.

STUDY DESIGN

Interrupted time-series analyses.

SETTING & PARTICIPANTS

Adult US HD patients represented in the US Renal Data System between 2008 and 2013.

EXPOSURES

PPS implementation.

OUTCOMES

The cumulative dose of IV vitamin D analogues (paricalcitol equivalents) per patient per calendar quarter in prevalent HD patients. The average starting dose of IV vitamin D analogues and quarterly rates of new vitamin D use (initiations/100 person-months) in incident HD patients within 90 days of beginning HD therapy.

ANALYTICAL APPROACH

Segmented linear regression models of the immediate change and slope change over time of vitamin D use after PPS implementation.

RESULTS

Among 359,600 prevalent HD patients, IV vitamin D analogues accounted for 99% of the total use, and this trend was unchanged over time. PPS resulted in an immediate 7% decline in the average dose of IV vitamin D analogues (average baseline dose = 186.5 μg per quarter; immediate change = -13.5 μg [P < 0.001]; slope change = 0.43 per quarter [P = 0.3]) and in the starting dose of IV vitamin D analogues in incident HD patients (average baseline starting dose = 5.22 μg; immediate change = -0.40 μg [P < 0.001]; slope change = -0.03 per quarter [P = 0.03]). The baseline rate of vitamin D therapy initiation among 99,970 incident HD patients was 44.9/100 person-months and decreased over time, even before PPS implementation (pre-PPS β = -0.46/100 person-months [P < 0.001]; slope change = -0.19/100 person-months [P = 0.2]). PPS implementation was associated with an immediate change in initiation levels (by -4.5/100 person-months; P < 0.001).

LIMITATIONS

Incident HD patients were restricted to those 65 years or older.

CONCLUSION

PPS implementation was associated with a 7% reduction in the average dose and starting dose of IV vitamin D analogues and a 10% reduction in the rate of vitamin D therapy initiation.

Strengthening Renal Registries and ESRD Research in Africa

In Africa, the combination of noncommunicable diseases, infectious diseases, exposure to environmental toxins, and acute kidney injury related to trauma and childbirth are driving an epidemic of chronic kidney disease and end-stage renal disease (ESRD). Good registry data can inform the planning of renal services and can be used to argue for better resource allocation, audit the delivery and quality of care, and monitor the impact of interventions. Few African countries have established renal registries and most have failed owing to resource constraints. In this article we briefly review the burden of chronic kidney disease and ESRD in Africa, and then consider the research questions that could be addressed by renal registries. We describe examples of the impact of registry data and summarize the sparse primary literature on country-wide renal replacement therapy in African countries over the past 20 years. Finally, we highlight some initiatives and opportunities for strengthening research on ESRD and renal replacement therapy in Africa. These include the establishment of the African Renal Registry and the availability of new areas for research. We also discuss capacity building, collaboration, open-access publication, and the strengthening of local journals, all measures that may improve the quantity, visibility, and impact of African research outputs.

Evidence basis for integrated management of mineral metabolism in patients with end-stage renal disease

PURPOSE OF REVIEW

Treatment of mineral metabolism is a mainstay of dialysis care including some of its most widely used and costly pharmaceuticals. Although many mineral metabolites are associated with increased risk of mortality, cardiovascular disease, and other morbidities, few clinical trials are available to guide therapy and most focus on single drug approaches. In practice, providers manage many aspects of mineral metabolism simultaneously in integrated treatment approaches that incorporate multiple agents and changes in the dialysis prescription. The present review discusses the rationale and existing evidence for evaluating integrated, as opposed to single drug, approaches in mineral metabolism.

RECENT FINDINGS

Drugs used to treat mineral metabolism have numerous, and sometimes, opposing effects on biochemical risk factors, such as fibroblast growth factor 23 (FGF23), calcium, and phosphorus. Although vitamin D sterols raise these risk markers when lowering parathyroid hormone (PTH), calcimimetics lower them. Trials demonstrate that combined approaches best 'normalize' the mineral metabolism axis in end-stage renal disease (ESRD). Observations embedded within major trials of calcimimetics reveal that adjustment of calcium-based binders and dialysate calcium is a common approach to adverse effects of these drugs with some initial, but inconclusive, evidence that these co-interventions may impact outcomes.

SUMMARY

The multiple, and often opposing, biochemical effects of many mineral metabolism drugs provides a strong rationale for studying integrated management strategies that consider combinations of drugs and co-interventions as a whole. This remains a current gap in the field with opportunities for clinical trials.

Attainment of guideline targets in EURODOPPS haemodialysis patients: are differences related to a country's healthcare expenditure and nephrologist workforce?

Background

In the field of chronic kidney disease, global clinical practice guidelines have been developed and implemented with a view to improving patient care and outcomes. The attainment of international and European guideline targets for haemodialysis patients in European countries has not been audited recently. Hence, we sought to establish whether the attainment of the targets set out in guidelines and inappropriate care are similar across European countries and whether inter-country differences are related to disparities in national healthcare expenditures (as a percentage of gross domestic product) and/or the nephrologist workforce per capita.

Methods

EURODOPPS is the European part of an international, prospective study of a cohort of adult, in-centre, haemodialysed patients. For the current project, 6317 patients from seven European countries were included between 2009 and 2011. Data on laboratory test results and medication prescriptions were extracted from patient records, in order to determine the overall percentage of patients treated according to the international guidelines on anaemia, dyslipidaemia, metabolic acidosis and mineral bone disease. Data related to macroeconomic indices were collected from World Health Organization database and World Bank stats.

Results

Attainment of the targets set in international guidelines was far from complete; only 34.1% of patients attained their target blood pressure and 31.2% attained their target haemoglobin level. Overall, only 5% of the patients attained all of the studied guideline targets. We observed marked inter-country differences in levels of guideline uptake/application and the use of pharmacological agents. The levels of national healthcare expenditures and nephrologist workforce were not correlated with the percentage of patients on-target for ≥50% of the studied variables or with inappropriate care (except for anaemia).

Conclusions

Our analysis of EURODOPPS data highlighted a low overall level of guideline target attainment in Europe and substantial differences between European countries. These inter-country differences did not appear to be linked to macroeconomic determinants.

CKD-MBD management: what is the role of parathyroidectomy? Results from a nationwide survey in Italy

We herein report on a nationwide survey conducted in Italy to investigate the use of parathyroidectomy (PTX). In spite of the availability of newer and more effective drugs to control chronic kidney disease mineral bone disorder (CKD-MBD) biochemical abnormalities, PTX still remains a resource for nephrologists to use. However, observational analyses suggest that in recent years there has been a constant decline in the number of patients undergoing PTX. The reasons are not clear, though the increasing age and number of comorbidities of dialysis patients may partly explain this trend. Poor adherence to guidelines and/or geographical as well as logistic factors may also contribute to the lower use of PTX. The working group on CKD-MBD of the Italian Society of Nephrology launched a nationwide survey to investigate clinical practice patterns for PTX in Italy and identify modifiable factors that may limit accessibility to surgery.

Coronary artery calcification in Korean patients with incident dialysis

INTRODUCTION

Patients with chronic kidney disease have an extremely high risk of developing cardiovascular disease (CVD). In patients with end-stage renal disease (ESRD), coronary artery calcification (CAC) is associated with increased mortality from CVD.

METHODS

The present study aimed to investigate the risk factors for CAC in Korean patients with incident dialysis. Data on 423 patients with ESRD who started dialysis therapy between December 2012 and March 2014 were obtained from 10 university-affiliated hospitals. CAC was identified by using noncontrast-enhanced cardiac multidetector computed tomography. The CAC score was calculated according to the Agatston score, with CAC-positive subjects defined by an Agatston score >0.

FINDINGS

Patients' mean age was 55.6 ± 14.6 years, and 64.1% were men. The CAC-positive rate was 63.8% (270 of 423). Results of univariate analyses showed significant differences in age, sex, etiology of ESRD and comorbid conditions according to the CAC score. However, results of multiple regression analysis showed that only a higher age was significantly associated with the CAC score. Receiver operating characteristic curves showed that the sensitivity and specificity of L-spine radiography for diagnosing CAC were 56% and 91%, respectively, for diagnosing CAC (area under the curve, 0.735).

DISCUSSION

CAC was frequent in patients with incident dialysis, and multiple regression analysis showed that only age was significantly associated with the CAC score. In addition, L-spine radiography could be a helpful modality for diagnosing CAC in patients with incident dialysis.

We Use Too Much Vitamin D in Hemodialysis Patients

Current Kidney Disease Improving Global Outcomes guidelines for chronic kidney disease-mineral and bone disorder recommend maintaining the PTH level between 2 and 9 times the upper limit of normal. PTH levels function as a surrogate for bone turnover to differentiate forms of renal osteodystrophy. Vitamin D receptor agonists are primarily used to treat osteitis fibrosa in hemodialysis patients. However, there is concern that overtreatment may put HD patients at risk for adynamic bone disease, which has been associated with fracture and vascular calcification. This raises the issue as to whether "we use too much vitamin D in hemodialysis patients."