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Introduction: More men than women start kidney replacement therapy (KRT) although the prevalence of chronic kidney disease (CKD) is higher in women than men. We therefore aimed at analyzing sex-specific differences in clinical outcomes among 8237 individuals with CKD in stages 3 to 5 from Brazil, France, Germany, and the United States participating in the Chronic Kidney Disease Outcomes and Practice Patterns Study (CKDopps). Methods: Fine and Gray models, evaluating the effect of sex on time to events, were adjusted for age, Black race (model A); plus diabetes, cardiovascular disease, albuminuria (model B); plus estimated glomerular filtration rate (eGFR) slope during the first 12 months after enrollment and first eGFR after enrollment (model C). Results: There were more men than women at baseline (58% vs. 42%), men were younger than women, and men had higher eGFR (28.9 ± 11.5 vs. 27.0 ± 10.8 ml/min per 1.73 m2). Over a median follow-up of 2.7 and 2.5 years for men and women, respectively, the crude dialysis initiation and pre-emptive transplantation rates were higher in men whereas that of pre-KRT death was more similar. The adjusted subdistribution hazard ratios (SHRs) between men versus women for dialysis were 1.51 (1.27–1.80) (model A), 1.32 (1.10–1.59) (model B), and 1.50 (1.25–1.80) (model C); for pre-KRT death, were 1.25 (1.02–1.54) (model A), 1.14 (0.92–1.40) (model B), and 1.15 (0.93–1.42) (model C); for transplantation, were 1.31 (0.73–2.36) (model A), 1.44 (0.76–2.74) (model B), and 1.53 (0.79–2.94) (model C). Conclusion: Men had a higher probability of commencing dialysis before death, unexplained by CKD progression alone. Although the causal mechanisms are uncertain, this finding helps interpret the preponderance of men in the dialysis population.

Rationale & Objective: Anemia management in patients treated with maintenance dialysis remains a challenge. We sought to update information in this area by evaluating the association between hemoglobin and various outcome and utilization measures using data-rich Medicare sources. Study Design: Observational cohort study using data from the Consolidated Renal Operations in a Web-enabled Network and Medicare claims. Setting & Participants: We studied 371,250 prevalent patients treated with hemodialysis, covering 3,326,072 patient-months in 2019. Exposure: Monthly patient hemoglobin concentrations. Outcomes: We examined several outcomes, including mortality, all-cause hospitalization, cause-specific hospitalization, and emergency department utilization in the month following the exposure measurement. Analytical Approach: For each monthly observation period, we calculated unadjusted and adjusted (for demographics and comorbid condition) hazard ratios using Cox regression. Results: The hemoglobin concentration was 11.5 g/dL. All-cause hospitalization, cause-specific hospitalization (including cardiovascular, infection, and several subcategories including coronavirus disease 2019 hospitalization), and emergency department utilization were inversely associated with hemoglobin concentration, with risk reduction stabilizing at hemoglobin levels of approximately 11.5-12 g/dL and higher. Limitations: As with prior observational studies, the observed associations are not necessarily causal. Conclusions: In a large US hemodialysis population, there were better clinical outcomes at higher hemoglobin concentrations over short exposure and follow-up periods, consistent with other observational studies that generally used longer exposure and follow-up times. Mortality risk increased at hemoglobin concentrations >11.5 g/dL, consistent with findings from erythropoiesis-stimulating agent clinical trials. The apparently beneficial short-term effects associated with higher hemoglobin concentrations suggest that hemoglobin measurements capture unmeasured elements of patient risk.

Mineral bone disorder (MBD) is a frequent consequence of chronic kidney disease, more so in patients with kidney failure treated by kidney replacement therapy. Despite the wide availability of interventions to control serum phosphate and parathyroid hormone levels, unmet gaps remain on optimal targets and best practices, leading to international practice pattern variations over time. In this Special Report, we describe international trends from the Dialysis Outcomes and Practice Patterns Study (DOPPS) for MBD biomarkers and treatments from 2002-2021, including data from a group of 7 European countries (Belgium, France, Germany, Italy, Spain, Sweden, United Kingdom), Japan, and the United States. From 2002-2012, mean phosphate levels declined in Japan (5.6 to 5.2 mg/dL), Europe (5.5 to 4.9 mg/dL), and the United States (5.7 to 5.0 mg/dL). Since then, levels rose in the United States (to mean 5.6 mg/dL, 2021), were stable in Japan (5.3 mg/dL), and declined in Europe (4.8 mg/dL). In 2021, 52% (United States), 27% (Europe), and 39% (Japan) had phosphate >5.5 mg/dL. In the United States, overall phosphate binder use was stable (80%-84% over 2015-2021), and parathyroid hormone levels rose only modestly. Although these results potentially stem from pervasive knowledge gaps in clinical practice, the noteworthy steady increase in serum phosphate in the United States over the past decades may be consequential to patient outcomes, an uncertainty that hopefully will soon be addressed by ongoing clinical trials. The DOPPS will continue to monitor international trends as new interventions and strategies ensue for MBD management in chronic kidney disease.

Abstract Background The Japanese Society for Dialysis Therapy (JSDT) published in 2013 inaugural hemodialysis (HD) guidelines. Specific targets include 1.4 for single-pool Kt/V (spKt/V) with a minimum dose of 1.2, minimum dialysis session length of 4 hours, minimum blood flow rate (BFR) of 200 mL/min, fluid removal rate no more than 15 mL/kg/hr, and hemodiafiltration (HDF) therapy for certain identified symptoms. We evaluated the effect of these guidelines on actual practice in the years spanning 2005 – 2018. Methods Analyses were carried out to describe trends in the above HD prescription practices from December 2005 to April 2013 (before guideline publication) to August 2018 based on prevalent patient cross-sections from approximately 60 randomly selected HD facilities participating in the Japan Dialysis Outcomes and Practice Patterns Study. Results From April 2006 to August 2017 continual rises occurred in mean spKt/V (from 1.35 to 1.49), and percent of patients having spKt/V>1.2 (71% to 85%). Mean BFR increased with time from 198.3 mL/min (April 2006) to 218.4 mL/min (August 2017) , along with percent of patients with BFR >200 ml/min (65% to 85%). HDF use increased slightly from 6% (April 2006 and August 2009) to 8% by April 2013, but increased greatly thereafter to 23% by August 2017. In contrast, mean HD treatment time showed little change from 2006-2017, whereas mean UFR declined from 11.3 in 2006 to 8.4 mL/Kg/hour in 2017. Conclusions From 2006 – 2018 Japanese HD patients experienced marked improvement in reaching the spKt/V target specified by the 2013 JSDT guidelines. This may have been due to moderate increase in mean BFR even though mean HD session length did not change much. In addition, HDF use increased dramatically in this time period. Other HD delivery changes during this time, such as increased use of super high flux dialyzers, also merit study. While we cannot definitively conclude a causal relationship between the publication of the guidelines and the subsequent practice changes in Japan, those changes moved practice closer to the recommendations of the guidelines.

Abstract Background Wasting is a common complication of kidney failure that leads to weight loss and poor outcomes. Recent experimental data identified parathyroid hormone (PTH) as a driver of adipose tissue browning and wasting, but little is known about the relations among secondary hyperparathyroidism, weight loss, and risk of mortality in dialysis patients. Methods We included 42,319 chronic in‐centre haemodialysis patients from the Dialysis Outcomes and Practice Patterns Study phases 2–6 (2002–2018). Linear mixed models were used to estimate the association between baseline PTH and percent weight change over 12 months, adjusting for country, demographics, comorbidities, and labs. Accelerated failure time models were used to assess 12 month weight loss as a mediator between baseline high PTH and mortality after 12 months. Results Baseline PTH was inversely associated with 12 month weight change: 12 month weight loss >5% was observed in 21%, 18%, 18%, 17%, 15%, and 14% of patients for PTH ≥600 pg/mL, 450–600, 300–450, 150–300, 50–150, and

As the worst global pandemic of the past century, coronavirus disease 2019 (COVID-19) has had a disproportionate effect on maintenance dialysis patients and their health care providers. At a virtual roundtable on June 12, 2020, Dialysis Outcomes and Practice Patterns Study (DOPPS) investigators from 15 countries in Asia, Europe, and the Americas described and compared the effects of COVID-19 on dialysis care, with recent updates added. Most striking is the huge difference in risk to dialysis patients and staff across the world. Per-population cases and deaths among dialysis patients vary more than 100-fold across participating countries, mirroring burden in the general population. International data indicate that the case-fatality ratio remains at 10% to 30% among dialysis patients, confirming the gravity of infection, and that cases are much more common among in-center than home dialysis patients. This latter finding merits urgent study because in-center patients often have greater community exposure, and in-center transmission may be uncommon under optimal protocols. Greater telemedicine use is a welcome change here to stay, and our community needs to improve emergency planning and protect dialysis staff from the next pandemic. Finally, the pandemic’s challenges have prompted widespread partnering and innovation in kidney care and research that must be sustained after this global health crisis.

Introduction: Dipeptidyl peptidase-4 (DPP-4) has been hypothesized to improve responsiveness to erythropoiesis-stimulating agent (ESA). We aimed to describe the trend in DPP-4 inhibitor prescription patterns and assess the association between DPP-4 inhibitor prescription and ESA hyporesponsiveness (eHypo) in Japanese hemodialysis (HD) patients with diabetes mellitus (DM). Methods: We analyzed data from the Japan Dialysis Outcomes and Practice Patterns Study phase 4–6 (2009–2017) on patients with DM who underwent HD thrice per week for at least 4 months. The primary exposure of interest was having a DPP-4 inhibitor prescription. The primary analysis outcomes were a binary indicator of eHypo (mean hemoglobin 6,000 units/week over 4 months) and the natural log-transformed ESA resistance index (ERI). We used conditional logistic regression to compare within-patient changes in eHypo before and after initial DPP-4 inhibitor prescription. We used linear generalized estimating equation models to compare continuous ERI outcomes while accounting for within-patient repeated measurements with an exchangeable correlation structure. Results: There was a monotonic increase in DPP-4 inhibitor prescription according to study year up to 20% in 2017. Moreover, 12.8% of patients with a DPP-4 inhibitor prescription were ESA hyporesponsive before the initial DPP-4 inhibitor prescription. After DPP-4 inhibitor prescription, the odds of eHypo and mean log-ERI remained unchanged in the whole cohort of our study. The interaction analysis of DPP-4 inhibitor and sideropenia showed that DPP-4 inhibitors attenuated eHypo in the patients without iron deficiency. Conclusion: Our findings indicate a recent increase in DPP-4 inhibitor prescription among Japanese HD patients with DM. DPP-4 inhibitors could improve ERI in patients undergoing HD without iron deficiency.

Introduction: The uptake of the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 chronic kidney disease (CKD) Guideline is not fully described in real-world nephrology practice across the world. Methods: We used baseline data from the CKD Outcomes and Practice Patterns Study (2013–2017), a 4-country cohort of patients with estimated glomerular filtration rate

Abstract The identification of malnutrition-inflammation-complex (MIC) and functional status (FS) is key to improving patient experience on hemodialysis (HD). We investigate the association of MIC and FS combinations with mortality in HD patients. We analyzed data from 5630 HD patients from 9 countries in DOPPS phases 4–5 (2009–2015) with a median follow-up of 23 [IQR 11, 31] months. MIC was defined as serum albumin 3 mg/L in Japan and > 10 mg/L elsewhere. FS score was defined as the sum of scores from the Katz Index of Independence in Activities of Daily Living and the Lawton-Brody Instrumental Activities of Daily Living Scale. We investigated the association between combinations of MIC (+/−) and FS (low [

Abstract Previously lacking in the literature, we describe longitudinal patterns of anemia prescriptions for non-dialysis-dependent chronic kidney disease (NDD-CKD) patients under nephrologist care. We analyzed data from 2818 Stage 3-5 NDD-CKD patients from Brazil, Germany, and the US, naïve to anemia medications (oral iron, intravenous [IV] iron, or erythropoiesis stimulating agent [ESA]) at enrollment in the CKDopps. We report the cumulative incidence function (CIF) of medication initiation stratified by baseline characteristics. Even in patients with hemoglobin (Hb)

Rationale & Objective: Some US hemodialysis (HD) facilities switched from oral cinacalcet to intravenous etelcalcetide as the primary calcimimetic therapy to control parathyroid hormone (PTH) levels after the introduction of etelcalcetide in 2017. Although clinical trials have demonstrated the superior efficacy of etelcalcetide versus cinacalcet, evidence comparing real-world effectiveness is lacking. Study Design: Prospective cohort. Setting & Participants: Patients receiving HD enrolled in US Dialysis Outcomes and Practice Patterns Study facilities. Exposure: We classified HD facilities on the basis of whether >75% of calcimimetic users were prescribed etelcalcetide (“etelcalcetide-first”) or cinacalcet (“cinacalcet-first”) from March-August 2019. Outcomes: PTH, calcium, and phosphorus levels among calcimimetic users, all averaged in the 6 months after the exposure assessment period. Analytical Approach: We used adjusted linear regression to compare outcomes using 2 approaches: (1) cross-sectional comparison of etelcalcetide-first and cinacalcet-first HD facilities; (2) pre-post comparison of HD facilities that switched from cinacalcet-first to etelcalcetide-first using facilities that remained cinacalcet-first as a comparison group. Results: We identified 45 etelcalcetide-first and 67 cinacalcet-first HD facilities; etelcalcetide-first (vs cinacalcet-first) facilities were more likely to be from small or independent dialysis organizations (86% vs 22%) and had higher total calcimimetic use (43% vs 29%) and lower active vitamin D use (66% vs 82%). In the cross-sectional analysis comparing etelcalcetide-first and cinacalcet-first HD facilities, the adjusted mean difference in PTH levels was −115 pg/mL (95% CI, −196 to −34) and the prevalence of a PTH level of >600 pg/mL was lower (prevalence difference, −11.4%; 95% CI, −19.3% to −3.5%). Among facilities that switched to etelcalcetide-first, the mean PTH level decreased from 671 to 484 pg/mL and the prevalence of a PTH level of >600 pg/mL decreased from 39% to 21%. Among facilities that remained cinacalcet-first, the mean PTH level increased from 632 to 698 pg/mL and the prevalence of a PTH level of >600 pg/mL increased from 37% to 43%. The adjusted difference-in-difference between the switch to etelcalcetide-first and the continuation of cinacalcet-first was −169 pg/mL (−249 to −90 pg/mL) for the mean PTH and −14.4% (−22.0% to −6.8%) for a PTH level of >600 pg/mL. We also observed slightly lower serum calcium levels and minimal differences in serum phosphorus levels between the etelcalcetide-first and the cinacalcet-first facilities. Limitations: Residual confounding. Conclusions: We observed better PTH control in HD facilities that switched from using cinacalcet to etelcalcetide as the primary calcimimetic therapy. Further research is needed to investigate how the greater real-world effectiveness of intravenous etelcalcetide (vs oral cinacalcet) may affect clinical outcomes.

Introduction: Prior cross-sectional studies suggest that health-related quality of life (HRQOL) worsens with more severe glomerular disease. This longitudinal analysis was conducted to assess changes in HRQOL with changing disease status. Methods: Cure Glomerulonephropathy (CureGN) is a cohort of patients with minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, IgA vasculitis, or IgA nephropathy. HRQOL was assessed at enrollment and follow-up visits 1 to 3 times annually for up to 5 years with the Patient-Reported Outcomes Measurement Information System (PROMIS). Global health, anxiety, and fatigue domains were measured in all; mobility was measured in children; and sleep-related impairment was measured in adults. Linear mixed effects models were used to evaluate HRQOL responsiveness to changes in disease status. Results: A total of 469 children and 1146 adults with PROMIS scores were included in the analysis. HRQOL improved over time in nearly all domains, though group-level changes were modest. Edema was most consistently associated with worse HRQOL across domains among children and adults. A greater number of symptoms also predicted worse HRQOL in all domains. Sex, age, obesity, and serum albumin were associated with some HRQOL domains. The estimated glomerular filtration rate (eGFR) was only associated with fatigue and adult physical health; proteinuria was not associated with any HRQOL domain in adjusted models. Conclusion: HRQOL measures were responsive to changes in disease activity, as indicated by edema. HRQOL over time was not predicted by laboratory-based markers of disease. Patient-reported edema and number of symptoms were the strongest predictors of HRQOL, highlighting the importance of the patient experience in glomerular disease. HRQOL outcomes inform understanding of the patient experience for children and adults with glomerular diseases.

Abstract Background The impact of anemia treatment with erythropoietin stimulating agents (ESA) on health-related quality of life (HRQOL) in chronic kidney disease (CKD) patients is controversial, particularly regarding optimal hemoglobin (Hb) target ranges. Methods We conducted a systematic review and meta-analysis of observational studies and randomized controlled trials (RCT) with ESA to estimate the effect of different achieved Hb values on physical HRQOL and functionality. We searched PubMed, EMBASE, CENTRAL, PEDro, PsycINFO and Web of Science databases, until May 2020. Two authors independently extracted data from studies. We included observational and RCTs that enrolled CKD patients undergoing anemia treatment with ESA with different achieved Hb levels among groups. We excluded studies with achieved Hb 11.5 g/dL. We analyzed the standardized mean difference (SMD) between groups for physical HRQOL. Results Among 8496 studies, fifteen RCTs and five observational studies were included for the systematic review. We performed the meta-analysis in a subset of eleven eligible RCTs. For physical role and physical function, SMDs were 0.0875 [95% CI: − 0.0025 – 0.178] and 0.08 [95% CI: − 0.03 – 0.19], respectively. For fatigue, SMD was 0.16 [95% CI: 0.09–0.24]. Subgroup analysis showed that trials with greater achieved Hb had greater pooled effects sizes — 0.21 [95% CI: 0.07–0.36] for Hb > 13 g/dL vs. 0.09 [95% CI: 0.02–0.16] for Hb 11.5–13 g/dL. Proportion of older and long-term diabetic patients across studies were associated with lower effect sizes. Conclusion Achieved hemoglobin higher than currently recommended targets may be associated with small but potentially clinically significant improvement in fatigue, but not in physical role or physical function. Younger and non-diabetic patients may experience more pronounced benefits of higher Hb levels after treatment with ESAs.

Rationale & Objective: Potential surrogate end points for kidney failure have been proposed in chronic kidney disease (CKD); however, they must be evaluated to ensure accurate, powerful, and harmonized research, particularly among patients with advanced CKD. The aim of the current study was to investigate the power and predictive ability of surrogate kidney failure end points in a population with moderate-to-advanced CKD. Study Design: Analysis of longitudinal data of a large multinational CKD observational study (Chronic Kidney Disease Outcomes and Practice Patterns Study). Setting & Participants: CKD stage 3-5 patients from Brazil, France, Germany, and the United States. Outcomes: Reaching an estimated glomerular filtration rate (eGFR) < 15 mL/min/1.73 m2 or eGFR decline of ≥40%, and composite end points of these individual end points. Analytical Approach: Each end point was used as a time-varying indicator in the Cox model to predict the time to kidney replacement therapy (KRT; dialysis or transplant) and was compared by the number of events and prediction accuracy. Results: 8,211 patients had a median baseline eGFR of 27 mL/min/1.73 m2 (interquartile range, 21-36 mL/min/1.73 m2) and 1,448 KRT events over a median follow-up of 2.7 years (interquartile range, 1.2-3.0 years). Among CKD stage 4 patients, the eGFR < 15 mL/min/1.73 m2 end point had higher prognostic ability than 40% eGFR decline, but the end points were similar for CKD stage 3 patients. The combination of eGFR < 15 mL/min/1.73 m2 and 40% eGFR decline had the highest prognostic ability for predicting KRT, regardless of the CKD stage. Including KRT in the composite can increase the number of events and, therefore, the power. Limitations: Variable visit frequency resulted in variable eGFR measurement frequency. Conclusions: The composite end point can be useful for CKD progression studies among patients with advanced CKD. Harmonized use of this approach has the potential to accelerate the translation of new discoveries to clinical practice by identifying risk factors and treatments for kidney failure.

Introduction: Cardiovascular (CV) morbidity and mortality are excessively high among hemodialysis (HD) patients. Anemia is a common complication of chronic kidney disease (CKD) and a known risk factor for CV events. To understand the impact of the recent regulatory and guideline changes in anemia management, we examined regional CV event rates in high-risk and erythropoiesis-stimulating agent (ESA)−hyporesponsive HD patients. Methods: A prospective cohort study including 16,560 HD patients, 8660 CV high-risk, and 884 hyporesponsive to ESAs, from the Dialysis Outcomes and Practice Patterns Study (DOPPS) phase 4 (2009−2011) and phase 5 (2012−2015) was conducted to quantify all-cause mortality, major adverse cardiovascular events (MACE), and MACE plus heart failure and thromboembolic events (MACE+). Results: The MACE+ rates (per 100 patient-years) were highest in North America (NA) (19.4; 95% CI = 18.2−20.7), followed by Europe (EU) (17.4; 95% CI = 16.6−18.1) and lowest in Japan (7.5; 95% CI = 6.9−8.1). When restricted to the high CV risk population, rates increased by 36% in NA, 45% in EU, and 72% in Japan. Mortality accounted for >74% of MACE+ events. MACE+ rates in ESA-hyporesponsive patients and high CV risk patients were similar in NA and EU cohorts. There were minimal differences in outcomes between the DOPPS phases 4 and 5. Conclusion: Cardiovascular event rates are high in the HD population, vary by geographic region, and are substantially higher in high CV risk patients and ESA-hyporesponsive patients; however, the rates appear not to be affected by anemia guideline changes. The findings from this study will be essential to contextualize the design of future CV anemia-related outcome studies and clinical trials. Keywords: cardiovascular events, cohort study, DOPPS, ESA hyporesponsivness, hemodialysis

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. Index Words: Hemodialysis, mineral bone disorders, DOPPS, international comparisons, mineral markers

Abstract Background Patient-reported measures are increasingly recognized as important predictors of clinical outcomes in peritoneal dialysis (PD). We sought to understand associations between patient-reported perceptions of the advantages and disadvantages of PD and clinical outcomes. Methods In this cohort study, 2760 PD patients in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) completed a questionnaire on their PD experience, between 2014 and 2017. In this questionnaire, PDOPPS patients rated 17 aspects of their PD experience on a 5-category ordinal scale, with responses scored from − 2 (major disadvantage) to + 2 (major advantage). An advantage/disadvantage score (ADS) was computed for each patient by averaging their response scores. The ADS, along with each of these 17 aspects, were used as exposures. Outcomes included mortality, transition to hemodialysis (HD), patient-reported quality of life (QOL), and depression. Cox regression was used to estimate associations between ADS and mortality, transition to HD, and a composite of the two. Logistic regression with generalized estimating equations was used to estimate cross-sectional associations of ADS with QOL and depression. Results While 7% of PD patients had an ADS

Abstract Background Insulin resistance contributes to the metabolic syndrome, which is associated with the development of kidney disease. However, it is unclear if insulin resistance independently contributes to an increased risk of chronic kidney disease (CKD) progression or CKD complications. Additionally, predisposing factors responsible for insulin resistance in the absence of diabetes in CKD are not well described. This study aimed to describe factors associated with insulin resistance and characterize the relationship of insulin resistance to CKD progression, cardiovascular events and death among a cohort of non-diabetics with CKD. Methods Data was utilized from Chronic Renal Insufficiency Cohort Study participants without diabetes (N = 1883). Linear regression was used to assess associations with insulin resistance, defined using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). The relationship of HOMA-IR, fasting glucose, hemoglobin A1c (HbA1c), and C-peptide with CKD progression, cardiovascular events, and all-cause mortality was examined with Cox proportional hazards models. Results Novel positive associations with HOMA-IR included serum albumin, uric acid, and hemoglobin A1c. After adjustment, HOMA-IR was not associated with CKD progression, cardiovascular events, or all-cause mortality. There was a notable positive association of one standard deviation increase in HbA1c with the cardiovascular endpoint (HR 1.16, 95% CI: 1.00–1.34). Conclusion We describe potential determinants of HOMA-IR among a cohort of non-diabetics with mild-moderate CKD. HOMA-IR was not associated with renal or cardiovascular events, or all-cause mortality, which adds to the growing literature describing an inconsistent relationship of insulin resistance with CKD-related outcomes.

Background: High data quality is of crucial importance to the integrity of research projects. In the conduct of multi-center observational cohort studies with increasing types and quantities of data, maintaining data quality is challenging, with few published guidelines. Methods: The Cure Glomerulonephropathy (CureGN) Network has established numerous quality control procedures to manage the 70 participating sites in the United States, Canada, and Europe. This effort is supported and guided by the activities of several committees, including Data Quality, Recruitment and Retention, and Central Review, that work in tandem with the Data Coordinating Center to monitor the study. We have implemented coordinator training and feedback channels, data queries of questionable or missing data, and developed performance metrics for recruitment, retention, visit completion, data entry, recording of patient-reported outcomes, collection, shipping and accessing of biological samples and pathology materials, and processing, cataloging and accessing genetic data and materials. Results: We describe the development of data queries and site Report Cards, and their use in monitoring and encouraging excellence in site performance. We demonstrate improvements in data quality and completeness over 4 years after implementing these activities. We describe quality initiatives addressing specific challenges in collecting and cataloging whole slide images and other kidney pathology data, and novel methods of data quality assessment. Conclusions: This paper reports the CureGN experience in optimizing data quality and underscores the importance of general and study-specific data quality initiatives to maintain excellence in the research measures of a multi-center observational study.

Rationale & Objective: Transitions between dialysis modalities can be disruptive to care. Our goals were to evaluate rates of transition from peritoneal dialysis (PD) to in-center hemodialysis (HD), mortality, and transplantation among incident PD patients in the US Renal Data System from 1996 to 2015 and identify factors associated with these outcomes. Study Design: Observational registry-based retrospective cohort study. Setting & Participants: Medicare patients incident to end-stage renal disease (ESRD) from January 1, 1996, through December 31, 2011 (for adjusted analyses; through December 31, 2014, for unadjusted analyses), and treated with PD 1 or more days within 180 days of ESRD incidence (n = 173,533 for adjusted analyses; n = 219,787 for unadjusted analyses). Exposure & Predictors: Exposure: 1 or more days of PD. Predictors: patient- and facility-level characteristics obtained from Centers for Medicare & Medicaid Services Form 2728 and other data sources. Outcomes: Patients were followed up for 3 years until transition to in-center HD, death, or transplantation. Analytical Approach: Multivariable Cox regression was used to estimate hazards over time and associations with predictors. Results: Compared with earlier cohorts, recent incident PD patient cohorts had lower rates of death (48% decline) and transition to in-center HD (13% decline). Among many other findings, we found that: (1) rates of transition to in-center HD and death were lowest in the 2008 to 2011 cohort, (2) longer time receiving PD was associated with higher mortality risk but lower risk for transition to in-center HD, and (3) larger PD programs (≥25 vs ≤6 patients) displayed lower risks for death and transition to in-center HD. Limitations: Data collected on Form 2728 are only at the time of ESRD incidence and do not provide information at the time of transition to in-center HD, death, or transplantation. Conclusions: Rates of transition from PD to in-center HD and death rates for PD patients decreased over time and were lowest in PD programs with 25 or more patients. Implications of the observed improved technique survival warrant further investigation, focusing on modifiable factors of center-level performance to create opportunities for improved patient outcomes.

Abstract Background Patients reaching end-stage renal disease must make a difficult decision regarding renal replacement therapy (RRT) options. Because the choice between dialysis modalities should include patient preferences, it is critical that patients are engaged in the dialysis modality decision. As part of the Empowering Patients on Choices for RRT (EPOCH-RRT) study, we assessed dialysis patients’ perceptions of their dialysis modality decision-making process and the impact of their chosen modality on their lives. Methods A 39-question survey was developed in collaboration with a multi-stakeholder advisory panel to assess perceptions of patients on either peritoneal dialysis (PD) or in-center hemodialysis (HD). The survey was disseminated to participants in the large US cohorts of the Dialysis Outcomes and Practice Patterns Study (DOPPS) and the Peritoneal DOPPS (PDOPPS). Survey responses were compared between PD and in-center HD patients using descriptive statistics, adjusted logistic generalized estimating equation models, and linear mixed regression models. Results Six hundred fourteen PD and 1346 in-center HD participants responded. Compared with in-center HD participants, PD participants more frequently reported that they were engaged in the decision-making process, were provided enough information, understood differences between dialysis modalities, and felt satisfied with their modality choice. PD participants also reported more frequently than in-center HD participants that partners or spouses (79% vs. 70%), physician assistants (80% vs. 66%), and nursing staff (78% vs. 60%) had at least some involvement in the dialysis modality decision. Over 35% of PD and in-center HD participants did not know another dialysis patient at the time of their modality decision and over 60% did not know the disadvantages of their modality type. Participants using either dialysis modality perceived a moderate to high impact of dialysis on their lives. Conclusions PD participants were more engaged in the modality decision process compared to in-center HD participants. For both modalities, there is room for improvement in patient education and other support for patients choosing a dialysis modality.

Abstract Background High-circulating level of parathyroid hormone (PTH) is associated with elevated mortality in dialysis patients. The Japanese Society for Dialysis Therapy guideline suggests a lower PTH target than other international guidelines; thus, PTH control may differ in Japan compared with other regions, and be associated with mortality. Methods We analyzed data from hemodialysis patients with ≥3 measurements of PTH during the first 9 months after enrollment in the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases 4–5 (2009–2015). PTH control was assessed by the mean, slope, and mean squared error (MSE) of all PTH measurements over the 9-month run-in period. Distribution of each PTH control was assessed by regions (Europe/Australia/New Zealand [Eur/ANZ], Japan and North America) and dialysis vintage. Mortality rates were compared across PTH control categories using Cox regression models. Results Mean PTH was lower in Japan than in other regions across dialysis vintage categories. In patients with dialysis vintage 5% per month in Japan (48% of patients) versus Eur/ANZ (35%) and North America (35%). In patients with dialysis vintage > 1 year, Japanese patients maintained steady PTH, while patients in Eur/ANZ and North America were more likely to experience a PTH increase. Mean PTH was associated with mortality in the overall samples (highest mortality rate for PTH > 600 pg/mL, hazard ratio, 1.35; 95% confidence interval, 1.20 to 1.52 vs PTH 200–399 pg/mL), and the association was obvious in the prevalent patients (hazard ratio, 1.44; 95% confidence interval, 1.26 to 1.65). PTH slope and MSE did not show significant association with mortality in the overall sample as well as in subjects stratified both by region and dialysis vintage. Conclusion PTH control in hemodialysis patients, as measured by keeping a stable PTH level over 9 months, was observed in Japan contrasted with other regions. High PTH mean, but not increased PTH slope and MSE, was associated with mortality especially in prevalent patients.

Introduction: In China, a quarter of patients are undergoing 2-times weekly hemodialysis. Using data from the China Dialysis Outcomes and Practice Patterns Study (DOPPS), we tested the hypothesis that whereas survival and hospitalizations would be similar in the presence of residual kidney function (RKF), patients without RKF would fare worse on 2-times weekly hemodialysis. Methods: In our cohort derived from 15 units randomly selected from each of 3 major cities (total N = 45), we generated a propensity score for the probability of dialysis frequency assignment, estimated a survival function by propensity score quintiles, and averaged stratum-specific survival functions to generate mean survival time. We used the proportional rates model to assess hospitalizations. We stratified all analyses by RKF, as reported by patients (urine output

Abstract Background Anemia management protocols in hemodialysis (HD) units differ conspicuously regarding optimal intravenous (IV) iron dosing; consequently, patients receive markedly different cumulative exposures to IV iron and erythropoiesis-stimulating agents (ESAs). Complementary to IV iron safety studies, our goal was to gain insight into optimal IV iron dosing by estimating the effects of IV iron doses on Hgb, TSAT, ferritin, and ESA dose in common clinical practice. Methods 9,471 HD patients (11 countries, 2009-2011) in the DOPPS, a prospective cohort study, were analyzed. Associations of IV iron dose (3-month average, categorized as 0,

Introduction: The chronic kidney disease outcomes and practice patterns study (CKDopps) is an international observational, prospective, cohort study involving patients with chronic kidney disease (CKD) stages 3-5 [estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2, with a major focus upon care during the advanced CKD period (eGFR < 30 ml/min/1.73 m2)]. During a 1-year enrollment period, each one of the 22 selected clinics will enroll up to 60 advanced CKD patients (eGFR < 30 ml/min/1.73 m2 and not dialysis-dependent) and 20 earlier stage CKD patients (eGFR between 30-59 ml/min/1.73 m2). Exclusion criteria: age < 18 years old, patients on chronic dialysis or prior kidney transplant. The study timeline include up to one year for enrollment of patients at each clinic starting in the end of 2013, followed by up to 2-3 years of patient follow-up with collection of detailed longitudinal patient-level data, annual clinic practice-level surveys, and patient surveys. Analyses will apply regression models to evaluate the contribution of patient-level and clinic practice-level factors to study outcomes, and utilize instrumental variable-type techniques when appropriate. Conclusion: Launching in 2013, CKDopps Brazil will study advanced CKD care in a random selection of nephrology clinics across Brazil to gain understanding of variation in care across the country, and as part of a multinational study to identify optimal treatment practices to slow kidney disease progression and improve outcomes during the transition period to end-stage kidney disease.