Regional Variation in Hemoglobin Distribution Among Individuals With CKD: the ISN International Network of CKD Cohorts.

Introduction: Despite recognized geographic and sex-based differences in hemoglobin in the general population, these factors are typically ignored in patients with chronic kidney disease (CKD) in whom a single therapeutic range for hemoglobin is recommended. We sought to compare the distribution of hemoglobin across international nondialysis CKD populations and evaluate predictors of hemoglobin. Methods: In this cross-sectional study, hemoglobin distribution was evaluated in each cohort overall and stratified by sex and estimated glomerular filtration rate (eGFR). Relationships between candidate predictors and hemoglobin were assessed from linear regression models in each cohort. Estimates were subsequently pooled in a random effects model. Results: A total of 58,613 participants from 21 adult cohorts (median eGFR range of 17-49 ml/min) and 3 pediatric cohorts (median eGFR range of 26-45 ml/min) were included with broad geographic representation. Hemoglobin values varied substantially among the cohorts, overall and within eGFR categories, with particularly low mean hemoglobin observed in women from Asian and African cohorts. Across the eGFR range, women had a lower hemoglobin compared to men, even at an eGFR of 15 ml/min (mean difference 5.3 g/l, 95% confidence interval [CI] 3.7-6.9). Lower eGFR, female sex, older age, lower body mass index, and diabetic kidney disease were all independent predictors of a lower hemoglobin value; however, this only explained a minority of variance (R2 7%-44% across cohorts). Conclusion: There are substantial regional differences in hemoglobin distribution among individuals with CKD, and the majority of variance is unexplained by demographics, eGFR, or comorbidities. These findings call for a renewed interest in improving our understanding of hemoglobin determinants in specific CKD populations.

International practice patterns of dyslipidemia management in patients with chronic kidney disease under nephrology care: is it time to review guideline recommendations?

BACKGROUND: In contrast to guidelines related to lipid therapy in other areas, 2012 Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommend conducting a lipid profile upon diagnosis of chronic kidney disease (CKD) and treating all patients older than 50 years without defining a target for lipid levels. We evaluated multinational practice patterns for lipid management in patients with advanced CKD under nephrology care. METHODS: We analyzed lipid-lowering therapy (LLT), LDL- cholesterol (LDL-C) levels, and nephrologist-specified LDL-C goal upper limits in adult patients with eGFR < 60 ml/min from nephrology clinics in Brazil, France, Germany, and the United States (2014-2019). Models were adjusted for CKD stage, country, cardiovascular risk indicators, sex, and age. RESULTS: LLT treatment differed significantly by country, from 51% in Germany to 61% in the US and France (p = 0.002) for statin monotherapy. For ezetimibe with or without statins, the prevalence was 0.3% in Brazil to 9% in France (< 0.001). Compared with patients not taking lipid-lowering therapy, LDL-C was lower among treated patients (p < 0.0001) and differed significantly by country (p < 0.0001). At the patient level, the LDL-C levels and statin prescription did not vary significantly by CKD stage (p = 0.09 LDL-C and p = 0.24 statin use). Between 7-23% of untreated patients in each country had LDL-C ≥ 160 mg/dL. Only 7-17% of nephrologists believed that LDL-C should be < 70 mg/dL. CONCLUSION: There is substantial variation in practice patterns regarding LLT across countries but not across CKD stages. Treated patients appear to benefit from LDL-C lowering, yet a significant proportion of hyperlipidemia patients under nephrologist care are not receiving treatment.

Patiromer utilization in patients with advanced chronic kidney disease under nephrology care in Germany.

Background: Hyperkalemia (HK) is a frequent condition in patients with chronic kidney disease (CKD) that is associated with high morbidity and mortality. Patiromer has recently been introduced as a potassium binder. Data on patiromer use in patients with CKD in the real-world setting in Europe are lacking. We describe time to discontinuation and changes in serum potassium levels among German CKD stage 3-5 patients starting patiromer. Methods: Duration of patiromer use was estimated by Kaplan-Meier curve, starting at patiromer initiation and censoring for death, dialysis, transplant or loss to follow-up. Serum potassium levels and renin-angiotensin-aldosterone system inhibitor (RAASi) use are described at baseline and during follow-up, restricted to patients remaining on patiromer. Results: We identified 140 patiromer users within our analysis sample [81% CKD stage 4/5, 83% receiving RAASi, and median K+ 5.7 (5.4, 6.3) mmol/L]. Thirty percent of patiromer users had prior history of polystyrene sulfonate use. Overall, 95% of patiromer users stayed on treatment past 1 month, with 53% continuing for over a year. Mean serum potassium levels decreased after patiromer initiation and remained stable under treatment during follow-up (up to 180 days). Among these patients, 73%-82% used RAASis during the time periods before and after patiromer initiation, with no obvious trend indicating discontinuation. Conclusion: Real-world evidence of patiromer use in Germany shows that, in line with what has been observed in clinical trials, patients on patiromer have a reduction in serum potassium when used long-term. Moreover, most patients on patiromer do not discontinue treatment prior to 1 year after initiation.

Economic burden of secondary hyperparathyroidism in Germany: a matched comparison.

PURPOSE: Secondary hyperparathyroidism (SHPT) of renal origin is a progressive complication in chronic kidney disease (CKD) and is associated with serious osseous and non-osseous complications, CKD progression, and economic burden for healthcare systems worldwide. We aimed at assessing characteristics, healthcare resource utilization, and costs of incident SHPT patients in CKD stage 3 (CKD3) and 4 (CKD4), using administrative claims data. METHODS: German claims data were used to identify CKD3 and CKD4 patients, who were stratified by the occurrence of incident SHPT. Patients with SHPT were matched 1:1 to non-SHPT patients with the same CKD stage using propensity scores. Matched groups were compared during a 2-year follow-up period. RESULTS: Overall, 1156 CKD3 and 517 CKD4 incident SHPT patients and their respective matches were identified. Mean number of all-cause hospitalizations were significantly higher among SHPT patients (2.7 vs. 2.0 in CKD3, 2.8 vs. 1.5 in CKD4) during follow-up. Similarly, the mean number of outpatient encounters was significantly higher among the SHPT cohorts (95.0 vs. 64.3 in CKD3, 101.4 vs. 49.8 in CKD4). SHPT patients progressed to CKD5 more often (6.1% vs. 1.2% from CKD3, 26.7% vs. 2.9% from CKD4, both P < 0.01) resulting in a higher proportion of dialysis (6.1% vs. 1.3% in CKD3, 22.1% vs. 3.7% in CKD4, both P < 0.01). Consequently, average all-cause healthcare costs significantly increased per patient (€19,477 vs. €15,115 in CKD3, €25,921 vs. €12,265 in CKD4). CONCLUSIONS: Patients with CKD3&4 and incident SHPT of renal origin presented with significantly higher healthcare resource utilization and costs, as well as increased disease progression compared to non-SHPT patients.

Understanding International Variations in Kidney Failure Incidence and Initiation of Replacement Therapy.

Introduction: Incidence of kidney replacement therapy (KRT) varies widely across countries. Its relations to individual characteristics, nephrology practices for slowing chronic kidney disease (CKD) progression, and KRT access remain unclear. Methods: We investigated intercountry differences in kidney failure (KF) rate, defined by a sustained estimated glomerular filtration rate (eGFR) <15 ml/min per 1.73 m2, and separately in KRT incidence, before and after adjusting for risk factors and blood pressure (BP) control or renin-angiotensin-aldosterone system inhibitor (RAASi) prescription practices in the CKD Outcomes and Practice Patterns Study (CKDopps) cohort study. Results: Among 7381 patients with CKD stage 3 to 4 at enrollment, 1297 progressed to KF and 947 initiated KRT over a 3-year follow-up period. Compared to the United States, demographic-adjusted and eGFR-adjusted hazard ratios (HRs) (HRs, 95% confidence intervals [CI]) for a sustained low eGFR were 0.77 (95% CI, 0.57-1.02) in Brazil, 0.90 (95% CI, 0.75-1.08) in France, and 1.03 (95% CI, 0.86-1.03) in Germany. Further adjustment for comorbidities, albuminuria, systolic BP, and RAASi prescription did not substantially change these HRs. In contrast, compared with the United States, the fully-adjusted HR for KRT remained significantly lower in Brazil (0.55, 95% CI 0.39-0.79), higher in Germany (95% CI, 1.36, 1.09-1.69), and similar in France (95% CI, 1.07, 0.81-1.39). Conclusion: Individual risk factors for CKD progression in nephrology patients appeared to explain most intercountry variations in KF but not KRT incidence. This suggests a prominent role for differences in practices related to KRT initiation or access, but not those for slowing disease progression. This study also shows that using KRT as a KF surrogate may bias estimates of associations with CKD progression risk factors.

Sex-Specific Differences in Mortality and Incident Dialysis in the Chronic Kidney Disease Outcomes and Practice Patterns Study.

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.

Serum Biomarkers of Iron Stores Are Associated with Increased Risk of All-Cause Mortality and Cardiovascular Events in Nondialysis CKD Patients, with or without Anemia.

BACKGROUND: Approximately 30%-45% of patients with nondialysis CKD have iron deficiency. Iron therapy in CKD has focused primarily on supporting erythropoiesis. In patients with or without anemia, there has not been a comprehensive approach to estimating the association between serum biomarkers of iron stores, and mortality and cardiovascular event risks. METHODS: The study included 5145 patients from Brazil, France, the United States, and Germany enrolled in the Chronic Kidney Disease Outcomes and Practice Patterns Study, with first available transferrin saturation (TSAT) and ferritin levels as exposure variables. We used Cox models to estimate hazard ratios (HRs) for all-cause mortality and major adverse cardiovascular events (MACE), with progressive adjustment for potentially confounding variables. We also used linear spline models to further evaluate functional forms of the exposure-outcome associations. RESULTS: Compared with patients with a TSAT of 26%-35%, those with a TSAT ≤15% had the highest adjusted risks for all-cause mortality and MACE. Spline analysis found the lowest risk at TSAT 40% for all-cause mortality and MACE. Risk of all-cause mortality, but not MACE, was also elevated at TSAT ≥46%. Effect estimates were similar after adjustment for hemoglobin. For ferritin, no directional associations were apparent, except for elevated all-cause mortality at ferritin ≥300 ng/ml. CONCLUSIONS: Iron deficiency, as captured by TSAT, is associated with higher risk of all-cause mortality and MACE in patients with nondialysis CKD, with or without anemia. Interventional studies evaluating the effect on clinical outcomes of iron supplementation and therapies for alternative targets are needed to better inform strategies for administering exogenous iron.

Adherence to the Kidney Disease: Improving Global Outcomes CKD Guideline in Nephrology Practice Across Countries.

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 <60 ml/min per 1.73 m2 recruited from national samples of nephrology clinics, to describe adherence to measures for monitoring and delaying CKD progression. Data were collected as in clinical practice, except laboratory measures per protocol in France. RESULTS: The mean age ranged from 65 years in Brazil to 72 years in Germany. Albuminuria (mostly proteinuria) was measured routinely in 36% to 43% of patients in Brazil, Germany, and the United States. Blood pressure control (≤140/90 mm Hg) ranged from 49% in France to 76% in Brazil; <40% of patients had blood pressure ≤130/80 mm Hg everywhere but Brazil (52%). More than 40% of nephrologists in Brazil reported a systolic blood pressure target ≤130 mm Hg for nondiabetic patients without proteinuria, but only 19% to 24% elsewhere. Prescription of renin-angiotensin aldosterone system inhibitors ranged from 52% in the United States to 81% in Germany. Dietary advice was more frequent for salt than protein intake; dietitian visits were uncommon. In nondiabetic patients, achievement of all 3 targets including blood pressure ≤130/80 mm Hg, renin-angiotensin aldosterone system inhibition, and dietary advice, ranged from 10% in the United States to 32% in Brazil; in treated diabetic patients, this ranged from 6% to 11% after including hemoglobin A1c target. CONCLUSION: Adherence to recommendations to slow CKD progression is low in typical practice settings, and substantial variation among countries for some indicates opportunities for improvement.

A real-world longitudinal study of anemia management in non-dialysis-dependent chronic kidney disease patients: a multinational analysis of CKDopps.

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) < 10 g/dL, the CIF at 12 months for any anemia medication was 40%, and 28% for ESAs. Patients with TSAT < 20% had a CIF of 26% and 6% for oral and IV iron, respectively. Heart failure was associated with earlier initiation of anemia medications. IV iron was prescribed to < 10% of patients with iron deficiency. Only 40% of patients with Hb < 10 g/dL received any anemia medication within a year. Discontinuation of anemia treatment was very common. Anemia treatment is initiated in a limited number of NDD-CKD patients, even in those with guideline-based indications to treat. Hemoglobin trajectory and a history of heart failure appear to guide treatment start. These results support the concept that anemia is sub-optimally managed among NDD-CKD patients in the real-world setting.

Anemia and iron deficiency among chronic kidney disease Stages 3-5ND patients in the Chronic Kidney Disease Outcomes and Practice Patterns Study: often unmeasured, variably treated.

BACKGROUND: International variation in anemia assessment and management practices in chronic kidney disease (CKD) is poorly understood. METHODS: We performed a cross-sectional analysis of anemia laboratory monitoring, prevalence and management in the prospective Chronic Kidney Disease Outcomes and Practice Patterns Study (CKDopps). A total of 6766 participants with CKD Stages 3a-5ND from nephrology clinics in Brazil, France, Germany and the USA were included. RESULTS: Among patients with anemia (hemoglobin <12 g/dL), 36-58% in Brazil, the USA and Germany had repeat hemoglobin measured and 40-61% had iron indices measured within 3 months of the index hemoglobin measurement. Anemia was more common in the USA and Brazil than in France and Germany across CKD stages. Higher ferritin and lower iron saturation (TSAT) levels were observed with lower hemoglobin levels, and higher ferritin with more advanced CKD. The proportion of anemic patients with ferritin <100 ng/mL or TSAT <20% ranged from 42% in Brazil to 53% in France and Germany, and of these patients, over 40% in Brazil, Germany and the USA, compared with 27% in France, were treated with oral or intravenous iron within 3 months after hemoglobin measurement. The proportion of patients with hemoglobin <10 g/dL treated with erythropoiesis-stimulating agents ranged from 28% in the USA to 57% in Germany. CONCLUSIONS: Hemoglobin and iron stores are measured less frequently than per guidelines. Among all regions, there was a substantial proportion of anemic patients with iron deficiency who were not treated with iron, highlighting an area for practice improvement in CKD care.

Chronic kidney disease progression and mortality risk profiles in Germany: results from the Chronic Kidney Disease Outcomes and Practice Patterns Study.

BACKGROUND: Chronic kidney disease (CKD) progression among German patients in a representative setting has not been described previously. The Verband Deutsche Nierenzentren and Chronic Kidney Disease Outcomes and Practice Patterns Study established a longitudinal observational cohort among German CKD patients to research variations in patient care and outcomes in real-world nephrology practices. METHODS: A cohort of CKD Stages 3 (25%) and 4 (75%) patients was established from German nephrologist-run CKD clinics in 2013-16. Linear models were used to determine the estimated glomerular filtration rate (eGFR) slope during follow-up and Cox models were used to assess outcomes of end-stage kidney disease (ESKD) and death. RESULTS: A total of 1834 patients (median age 75 years, 58% male, 42% diabetics, median baseline eGFR 25 mL/min/1.73 m2) were followed for a median of 29 months. More than 50% had slow or no decline and 17% declined ≥5 mL/min/1.73 m2/year. After 4.5 years, the incidence of ESKD was 8% and of deaths without ESKD 16% among patients with eGFR ≥30 mL/min/1.73 m2 and 37% and 19% for eGFR <30 mL/min/1.73 m2. Adjusted models showed higher risks of ESKD or death for patients with worse kidney function at baseline, male sex, diabetes and higher blood pressure; a higher risk of ESKD with higher albuminuria; and a higher risk of death with older age or cardiovascular comorbidity. CONCLUSIONS: Routine nephrology care of patients in Germany comprises mostly elderly patients, many with slow CKD progression. Identification of risk factors for CKD progression and mortality may help guide resources by closer follow-up of high-risk patients.

International variation in the management of mineral bone disorder in patients with chronic kidney disease: Results from CKDopps.

BACKGROUND AND OBJECTIVES: Chronic kidney disease (CKD) is commonly associated with mineral and bone metabolism disorders, but these are less frequently studied in non-dialysis CKD patients than in dialysis patients. We examined and described international variation in mineral and bone disease (MBD) markers and their treatment and target levels in Stage 3-5 CKD patients. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Prospective cohort study of 7658 adult patients with eGFR <60mL/min/1.73m2, excluding dialysis or transplant patients, participating in the Chronic Kidney Disease Outcomes and Practice Patterns Study (CKDopps) in Brazil, France, Germany, and the US. CKD-MBD laboratory markers included serum levels of phosphorus (P), calcium (Ca), intact parathyroid hormone (iPTH), and 25-hydroxyvitamin D (25-D). MBD treatment data included phosphate binders and vitamin D (nutritional and active). Nephrologist survey data were collected on target MBD marker levels. RESULTS: Over two-thirds of the patients had MBD markers measured at time intervals in line with practice guidelines. P and iPTH increased and Ca decreased gradually from eGFR 60-20mL/min/1.73m2 and more sharply for eGFR<20. 25-D showed no relation to eGFR. Nephrologist survey data indicated marked variation in upper target P and iPTH levels. Among patients with P>5.5mg/dL, phosphate binder use was 14% to 43% across the four countries. Among patients with PTH >300pg/mL, use of active (calcitriol and related analogs) vitamin D was 12%-51%, and use of any (active or nutritional) vitamin D was 60%-87%. CONCLUSIONS: Although monitoring of CKD-MBD laboratory markers by nephrologists in CKDopps countries is consistent with guidelines, target levels vary notably and prescription of medications to treat abnormalities in these laboratory markers is generally low in these cross-sectional analyses. While there are opportunities to increase treatment of hyperphosphatemia, hyperparathyroidism, and vitamin D deficiency in advanced CKD, the effect on longer-term complications of these conditions requires study.

Considerable international variation exists in blood pressure control and antihypertensive prescription patterns in chronic kidney disease.

Although blood pressure control is a major goal in chronic kidney disease, no worldwide overview of either its achievement or antihypertensive prescriptions is currently available. To evaluate this we compared crude prevalence of uncontrolled blood pressure among 17 cohort studies, including 34 602 individuals with estimated glomerular filtration rate under 60 ml/min/1.73 m2 and treated hypertension across four continents, and estimated observed to expected prevalence ratios, adjusted for potential confounders. Crude prevalence of blood pressure of 140/90 mm Hg or more varied from 28% to 61% and of blood pressure of 130/80 or more from 54% to 84%. Adjusted prevalence ratios indicated poorer hypertension control than expected in cohorts from European countries, India, and Uruguay, and better control in patients from North American and high-income Asian countries. Four antihypertensive drug classes or more were prescribed to more than 30% of participants in North American and some European cohorts, but this practice was less common elsewhere. Renin angiotensin-aldosterone system inhibitors were the most common antihypertensive drugs, prescribed for 54% to 91% of cohort participants. Differences for other drug classes were much stronger, ranging from 11% to 79% for diuretics, 22% to 70% for beta-blockers, and 27% to 75% for calcium-channel blockers. The confounders studied explain only a part of the international variation in blood pressure control among individuals with chronic kidney disease. Thus, considerable heterogeneity in prescription patterns worldwide calls for further investigation into the impact of different approaches on patient outcomes.

Prescription of renin-angiotensin-aldosterone system inhibitors (RAASi) and its determinants in patients with advanced CKD under nephrologist care.

Renin-angiotensin-aldosterone system inhibitors (RAASi) are recommended for chronic kidney disease (CKD) patients. In this study, we describe RAASi prescription patterns in the Chronic Kidney Disease Outcomes and Practice Patterns Study (CKDopps) in Brazil, Germany, France, and the United States (US). 5870 patients (mean age 66-72 years; congestive heart failure [CHF] in 11%-19%; diabetes in 43%-54%; serum potassium ≥5 in 20%-35%) were included. RAASi prescription was more common in Germany (80%) and France (77%) than Brazil (66%) and the United States (52%), where the prevalence of prescription decreases particularly in patients with CKD stage 5. In the multivariable regression model, RAASi prescription was least common in the United States and more common in patients who were younger, had diabetes, hypertension, or less advanced CKD. In conclusion, RAASi prescription patterns vary by country, and by demographic and clinical characteristics. RAASi appear to be underused, even among patients with strong class-specific recommendations. Although the reasons for this variation could not be fully identified in this cross-sectional observation, our data indicate that the risk of hyperkalemia may contribute to the underuse of this class of agents in moderate to advanced CKD.

Timely Referral to Outpatient Nephrology Care Slows Progression and Reduces Treatment Costs of Chronic Kidney Diseases.

INTRODUCTION: We present a new approach to evaluate the importance of ambulatory nephrology care in patients with chronic kidney disease (CKD). METHODS: An anonymized health claims database of German insurance companies was searched in a retrospective analysis for patients with CKD using the codes of the International Classification of Diseases, 10th German modification. A total of 105,219 patients with CKD were identified. Patients were assigned to the group "timely referral," when nephrology care was present in the starting year 2009, or initiated during the following 3 years in CKD1-4. Using frequency matching for age and gender, 21,024 of the late referral group were matched with the equal number of patients in the timely referral group. Hospital admission rates, total treatment costs, and kidney function (change in CKD stages, start of dialysis, mortality) were documented each year during the 4-year follow-up. RESULTS: Hospital admission rates (110%-186%) and total treatment costs (119%-160%) were significantly higher (P < 0.03) in late referral compared with timely referral. In the timely referral group, significantly more patients did not change their CKD stage (65%-72.9% vs. 52%-64.6%, P < 0.05) compared with late referral. Starting in CKD3 more patients tended to start dialysis in 1 year in timely referral (1.9 ± 0.6 vs. 1.0 ± 0.4, P = 0.1). In contrast, death rates were significantly higher in the late referral group (18.8 ± 1.8% vs. 6.7 ± 0.4%, P = 0.0001). DISCUSSION: Timely referral to outpatient nephrology care is associated with slowed disease progression, less hospital admissions, reduced total treatment costs, and improved survival in patients with CKD.

The CKD Outcomes and Practice Patterns Study (CKDopps): Rationale and Methods.

BACKGROUND: Minimizing clinical complications in patients with advanced chronic kidney disease (CKD) and improving the transition to dialysis therapy and transplantation represents a challenge, requiring reliable evidence regarding the effects of CKD care on outcomes. STUDY DESIGN: The CKD Outcomes and Practice Patterns Study (CKDopps) is a new international prospective cohort study designed to describe and evaluate variation in nephrologist-led CKD practices. SETTING & PARTICIPANTS: CKDopps is underway in Brazil, France, Germany, Japan, and the United States. Diverse national samples of nephrology clinics are being recruited based on random selection stratified by geographic region and clinic characteristics. CKDopps aims to enroll 12,200 non-dialysis-dependent patients with CKD (75% and 25% with estimated glomerular filtration rates < 30 and 30-<60mL/min/1.73m(2), respectively) to be followed up for 3 to 5 years. PREDICTORS: Demographic, comorbid condition, laboratory, and treatment-related variables are collected at 6-month intervals; patient-reported data are collected annually and more frequently near the transition to end-stage kidney disease; nephrologist practice surveys are collected annually. OUTCOMES: Outcomes include mortality, end-stage kidney disease, other clinical events (eg, acute kidney injury, hospitalizations, infections, cardiovascular events, and transplant wait-listing), and patient-reported outcomes. RESULTS: For the targeted sample size of 12,200 patients and 160 clinics, CKDopps has 80% power to detect HRs of 1.31 for mortality and 1.19 for mortality or transition to end-stage kidney disease. LIMITATIONS: CKDopps does not capture care provided in settings outside nephrology clinics (eg, primary care) or patients with CKD not receiving medical care. CONCLUSIONS: CKDopps is designed to characterize nephrology clinic practice variation and identify practices associated with better outcomes, with particular focus on advanced CKD, transition to end-stage kidney disease, and the patient experience. Because data will be collected during routine clinical care in real-world practice, analyses may yield practical readily implementable findings. CKDopps aims to establish a multinational infrastructure for research, collaboration, and ancillary investigation. Additional countries are encouraged to join.

Changes in dialysis treatment modalities during institution of flat rate reimbursement and quality assurance programs.

Dialysis procedure rates in Germany were changed in 2002 from per-session to weekly flat rate payments, and quality assurance was introduced in 2009 with defined treatment targets for spKt/V, dialysis frequency, treatment time, and hemoglobin. In order to understand trends in treatment parameters before and after the introduction of these changes, we analyzed data from 407 to 618 prevalent patients each year (hemodialysis over 90 days) in 14-21 centers in cross-sections of the Dialysis Outcomes and Practice Patterns Study (phases 1-4, 1998-2011). Descriptive statistics were used to report differences over time in the four quality assurance parameters along with erythropoietin-stimulating agent (ESA) and intravenous iron doses. Time trends were analyzed using linear mixed models adjusted for patient demographics and comorbidities. The proportion of patients with short treatment times (less than 4 h) and low spKt/V (below 1.2) improved throughout the study and was lowest after implementation of quality assurance. Hemoglobin levels have increased since 1998 and remained consistent since 2005, with only 8-10% of patients below 10 g/dl. About 90% of patients were prescribed ESAs, with the dose declining since peaking in 2006. Intravenous iron use was highest in 2011. Hence, trends to improve quality metrics for hemodialysis have been established in Germany even after introduction of flat rate reimbursement. Thus, analysis of facility practice patterns is needed to maintain quality of care in a cost-containment environment.

Implementation and first results of a German chronic kidney disease registry.

Advanced chronic kidney disease (CKD) is gaining increasing medical and economical importance, but little information exists about treatment variation and the impact of routine clinical treatments on survival, quality of life, and cost. We demonstrate the first results of a national electronic registry of nephrology clinic data that will serve as a resource for the prospective observation of CKD patients in Germany. A large network of German nephrologist practices is currently joining the project. Routinely obtained clinical data for non-dialysis dependent CKD patients are documented in health records electronically, and elements from these data are extracted using QuaNT (Qualitätssicherung Nephrologie und Transplantation) to create a centralized database. Here, we report cross-sectional data from 59 participating nephrology clinics and 6,187 patients with CKD Stage 3 - 5 in 2011. Mean age ± standard deviation (SD) was 72 ± 12 years. The distribution of CKD 3, 4, and 5 (non-dialysis) was 60%, 33%, and 8%, respectively. The major renal diseases were hypertension/vascular nephropathy (47%) and diabetic nephropathy (26%). Reninangiotensin-system inhibitor prescription was 78%. Vitamin D prescription was 50%, phosphate binders 6%, iron (oral or i.v.) 19%, and erythropoietin-stimulating agents 14%. This electronic registry follows clinical nephrology care and outcomes for CKD patients in Germany, and increased participation is anticipated. As a component of the initiative, variation in patient care will be studied to identify best treatment practices in analyses integrated into the international CKD Outcomes and Practice Patterns Study (CKDopps).

Efficacy and safety of lanthanum carbonate in German patients on dialysis.

AIMS: To assess the treatment efficacy and tolerability of lanthanum carbonate (LC) in patients with end-stage renal disease (ESRD) and hyperphosphatemia under daily-practice conditions. PATIENTS AND METHODS: 698 patients on dialysis in 116 outpatient dialysis centers in Germany were enrolled in this post-marketing surveillance study (mean treatment duration 6 months). LC treatment was compared to pretreatment (no or other phosphate binders) regarding laboratory parameters, adverse events and tablet burden. RESULTS: Compared to baseline, LC significantly reduced mean serum phosphate (SP), serum calcium, and calcium × phosphate product (p < 0.0001). In monotherapy with LC, mean tablet burden was decreased to 3.0 tablets per day thus reducing the mean pre-study phosphatebinder tablet burden by nearly 50%. Adverse drug reactions associated with LC were reported in only 2.0% of the patients (n = 14). Overall, LC was considered safe and well tolerated. CONCLUSIONS: Under daily-practice conditions, LC at an average dose of 2,509 ± 936 mg/d was well tolerated and effective in adjusting and maintaining control of SP in patients previously being unsatisfactorily controlled on other phosphate binders. The daily tablet burden with a phosphate binder can be reduced to 3 tablets of LC, particularly in patients on monotherapy. The lack of a comparison group should be considered in terms of careful interpretation of the study results.