NephroCare Centers Research Articles

The Use of Anemia Control Model Is Associated with Improved Hemoglobin Target Achievement, Lower Rates of Inappropriate Erythropoietin Stimulating Agents, and Severe Anemia among Dialysis Patients

Introduction: The Anemia Control Model (ACM) is a certified medical device suggesting the optimal ESA and iron dosage for patients on hemodialysis. We sought to assess the effectiveness and safety of ACM in a large cohort of hemodialysis patients. Methods: This is a retrospective study of dialysis patients treated in NephroCare centers between June 1, 2013 and December 31, 2019. We compared patients treated according to ACM suggestions and patients treated in clinics where ACM was not activated. We stratified patients belonging to the reference group by historical target achievement rates in their referral centers (tier 1: <70%; tier 2: 70–80%; tier 3: >80%). Groups were matched by propensity score. Results: After matching, we obtained four groups with 85,512 patient-months each. ACM had 18% higher target achievement rate, 63% smaller inappropriate ESA administration rate, and 59% smaller severe anemia risk compared to Tier 1 centers (all p < 0.01). The corresponding risk ratios for ACM compared to Tier 2 centers were 1.08 (95% CI: 1.08–1.09), 0.49 (95% CI: 0.47–0.51), and 0.64 (95% CI: 0.61–0.68); for ACM compared to Tier 3 centers, 1.01 (95% CI: 1.01–1.02), 0.66 (95% CI: 0.63–0.69), and 0.94 (95% CI: 0.88–1.00), respectively. ACM was associated with statistically significant reductions in ESA dose administration. Conclusion: ACM was associated with increased hemoglobin target achievement rate, decreased inappropriate ESA usage and a decreased incidence of severe anemia among patients treated according to ACM suggestion.

#3356 COVID-19 PANDEMIC EFFECT ON HOSPITALIZATION OF HEMODIALYSIS PATIENTS

Abstract Background and Aims During the COVID-19 pandemic many facets of our lives were affected, including the healthcare systems worldwide. We aimed to assess the hospitalization rates of hemodialysis (HD) patients with confirmed COVID-19 infection (COVID-19+) versus other patients (i.e., patients with no documented COVID-19 infection in the European Clinical Database (EuCliD®)) in 2020 and their relation to HD patients from the pre-pandemic era in 2019. Method We included 63,216 HD patients treated in 2019-2020 in NephroCare centers from 23 countries from EuCliD® in the Europe, Middle East, and Africa (EMEA) region. Monthly hospitalization rates (hospital admission per 10,000 patients) were estimated separately for COVID-19+ and other HD patients in 2020, and HD patients treated in 2019, with COVID-19+ status as a time-varying variable. The number of COVID-19 cases and deaths were extracted from data released by the European Commission Joint Research Centre (ECJRC)[1]. The correlation between the monthly hospitalization rates and numbers of COVID-19 cases and deaths in general population (GP) were evaluated. Results Characteristics of the approximately 42,000-43,000 monthly treated HD patients were comparable between 2019 and 2020 (Table 1). The hospitalization rates were much higher for COVID-19+ HD patients throughout 2020 compared to other HD patients in 2020 and HD patients in 2019. The hospitalization rates were highest in the spring of 2020 for COVID-19+ HD patients. However, in 2020 other HD patients’ hospitalization rates were lower than the 2019 HD patients’ hospitalization rates. Interestingly the hospitalization rates of other HD patients in 2020 dipped even more below hospitalizations for HD patients in 2019 following the GP pandemic waves (Figure 1). Hospital admission for both COVID-19+ and other HD patients were inversely correlation with the pandemic conditions in GP (Figure 2; spearman correlation coefficients [ρ] with COVID-19 cases/deaths in GP, -0.77/-0.22 and -0.29/-0.64, respectively, for COVID-19+ and other HD patients). Conclusion Our study indicated the COVID-19 pandemic had an impact on hospitalization rates of both HD patients with a COVID-19 diagnosis and those patients without a documented COVID-19 infection. Potential reasons of decreased hospitalization rates in patients without a documented COVID-19 diagnosis could be healthcare resource constraints or regarding patient concerns about exposure to COVID-19 in hospital settings [2].

Evolution of body composition and wasting indicators by time of day of haemodialysis.

It has been a long-standing clinical concern that haemodialysis (HD) patients on afternoon shifts (ASs) are more prone to protein-energy wasting (PEW) than those on morning shifts (MSs), as their dialysis scheme and post-dialysis symptoms may interfere with meal intake. We evaluated the effect of time of day of HD on the evolution of body composition changes and PEW surrogates. We conducted a retrospective study among 9.963 incident HD patients treated in NephroCare centres (2011-16); data were routinely collected in the European Clinical Database. The course of multi-frequency bioimpedance determined lean and fat tissue indices (LTI and FTI) between patients in MSs/ASs over 2 years were compared with linear mixed models. Secondary PEW indicators were body mass index, albumin, creatinine index and normalized protein catabolic rate. Models included fixed (age, sex, vascular access and diabetes mellitus) and random effects (country and patient). Mean baseline LTI and FTI were comparable between MSs (LTI: 12.5 ± 2.9 kg/m2 and FTI: 13.7 ± 6.0 kg/m2) and ASs (LTI: 12.4 ± 2.9 kg/m2 and FTI: 13.2 ± 6.1 kg/m2). During follow-up, LTI decreased and FTI increased similarly, with a mean absolute change (baseline to 24 months) of -0.3 kg/m2 for LTI and +1.0 kg/m2 for FTI. The course of these malnutrition indicators did not differ between dialysis shifts (P for interaction ≥0.10). We also did not observe differences between groups for secondary PEW indicators. This study suggests that a dialysis shift in the morning or in the afternoon does not impact the long-term nutritional status of HD patients. Regardless of time of day of HD, patients progressively lose muscle mass and increase body fat.

Serum Uric Acid and Mortality Risk Among Hemodialysis Patients

IntroductionAlthough high serum uric acid (SUA) has been consistently associated with an increased risk of death in the general population and in persons with nondialysis chronic kidney disease (CKD), studies in patients undergoing dialysis are conflicting. It has been postulated that low SUA simply reflects poor nutritional status in dialysis patients. We here characterize the association between SUA and the risk of death in a large dialysis cohort and explore effect modification by underlying nutritional status as reflected by body composition.MethodsIn this retrospective cohort study, we included 16,057 hemodialysis (HD) patients treated during 2007 to 2016 in NephroCare centers as recorded in the European Clinical Database (EuCliD). The association between SUA, all-cause, and cardiovascular (CV)−related mortality was evaluated with competing risk models and characterized with splines. Effect modification was explored by lean tissue index (LTI) and fat tissue index (FTI).ResultsDuring a mean of 1.8 years of follow-up, 2791 patients (17.4%) died. We found a multivariable-adjusted U-shaped pattern between SUA and all-cause mortality. Patients with SUA levels of 6.5 mg/dl (387 μmol/l) were at the lowest risk of death (subdistribution hazard ratio = 0.94 [confidence interval {CI} 0.91; 0.96]). The form of association was not meaningfully affected by underlying LTI and FTI.ConclusionWe found a U-shaped pattern between SUA levels and all-cause mortality among HD patients, which was independent of the patients’ body composition.

P1433VALIDATION OF A SERUM CALCIFICATION PROPENSITY TEST FOR THE PREDICTION OF ALL-CAUSE MORTALITY AMONG DIALYSIS PATIENTS

Abstract Background and Aims Vascular calcification as cause of vascular stiffness is a major contributor to the high cardiac burden among stage 5 chronic kidney disease dialysis (CKD5HD) patients. Early identification of patients with high calcification propensity is crucial for proper risk stratification and management of these patients. Recently, a novel in vitro test (T50-test) was developed which determines calcification propensity of human serum and predicts mortality among ND-CKD (non-dialysis chronic kidney disease) patients, kidney transplant recipients and CKD5HD patients suffering from secondary hyperparathyroidism. We now evaluated whether these results can be confirmed in an unselected cohort of CKD5HD patients and can be used in the future for improving care of these patients. Method This prospective clinical study included 776 incident and prevalent hemodialysis patients from 8 Fresenius Medical Care NephroCare centers in Cataluña (Spain). T50 was determined at Calciscon AG, all other clinical data were retrieved from the European Clinical Database (EuCliD®). After their baseline T50 measurement, patients were followed for two years for the occurrence of the primary endpoint all-cause mortality. The association between T50 and all-cause mortality was examined by using proportional subdistribution hazards regression modelling accounting for kidney transplantation as competing event. In sensitivity analyses we adjusted for age, sex, vascular access (fistula/graft, catheter), treatment modality (HD, HDF), Charlson comorbidity index and dialysis vintage. Results Mean age of the study population was 72.2 years and 63.8% were male. 42.5% had diabetes and 55.0% past history of cardiovascular disease. Mean T50 was 283.4 min among the total cohort. During follow-up, 185 (23.8%) patients died. Patients who reached the endpoint had a significantly lower T50 at baseline as compared to those who survived during follow-up (269.6 vs 287.7 min, p = 0.001). A cross-validated model (mean c statistic: 0.5767) identified T50 as a linear predictor of all-cause-mortality (subdistribution hazard ratio (per min): 0.9957, 95% CI [0.9933;0.9981]). T50 remained a significant predictor of all-cause mortality after adjusting for relevant confounding in sensitivity analyses. Conclusion In this prospective study, we confirmed that T50 is an independent predictor of all-cause mortality among a large unselected cohort of hemodialysis patients. T50 may be used to identify patients with high vascular calcification propensity and mortality risks and may help physicians to implement a personalized and more precise renal replacement therapy option.

Haemodialysis therapy and sustainable growth: a corporate experience in France.

IntroductionSustainable growth and environmental issues are currently a topic for all human activities, and dialysis represents a real challenge in this field because of high water and power consumption and the production of large amounts of care-related waste. In this article we describe data collection implemented in the NephroCare centres in France and the changes observed during a 13-year period regarding environmental parameters.MethodsMonthly data collection (eco-reporting) was implemented in NephroCare centres in France in 2005. It covers three topics designed as key performance indicators (KPIs): electricity and water consumption and care-related waste production expressed, respectively, as kilowatt-hour (kWh), litres (L) and kilograms per session. We report on the three action plans (2005–10, 2011–14 and 2015–18) and changes observed during this 13-year period.ResultsDuring the period, power and water consumption declined by 29.6% (from 23.1 to 16.26 kWh/session) and 52% (from 801 to 382 L/session), respectively. At the same time, the yearly number of dialysis sessions has increased from 169 335 to 399 336. The sources of savings came both from improvements in the dialysis technology (dialysis machines and water treatment systems) and from updating and remodelling of the dialysis unit equipment and buildings. The care-related waste decreased from 1.8 to 1.1 kg because of regular staff training and the retrofiltration system, allowing the voiding of the remaining saline solution after dialysis. These savings have been estimated as equivalent to 102 440 tons of carbon dioxide.DiscussionImplementation of KPIs and their regular monitoring by trained staff to evaluate water and power consumption and the reduction of care-related water production are essential to implement actions to reduce the impact of dialysis on the environment. These data show the importance of water treatment and dialysis technology to decrease water and power consumption and the production of care-related waste as well as upgrading or remodelling of buildings housing dialysis units. Other measures are discussed, including the reuse of rejected water by reverse osmosis, as well as behavioural changes that are needed to reach sustainable development of dialysis.ConclusionThe first step to reach ‘green’ dialysis is to collect precise information from defined KPIs. This is the only way to design action plans to reduce the impact of dialysis therapy on the environment. Beyond this, the nephrology community must be sensitized to this challenge to be proactive and to anticipate future regulations.

Is high-volume post-dilution haemodiafiltration associated with risk of fluid volume imbalance? A national multicentre cross-sectional cohort study.

BackgroundFluid overload is frequent among hemodialysis (HD) patients. Dialysis therapy itself may favor sodium imbalance from sodium dialysate prescription. As on-line hemodiafiltration (OL-HDF) requires large amounts of dialysate infusion, this technique can expose to fluid accumulation in case of a positive sodium gradient between dialysate and plasma. To evaluate this risk, we have analyzed and compared the fluid status of patients treated with HD or OL-HDF in French NephroCare centers.MethodThis is a cross-sectional and retrospective analysis of prevalent dialysis patients. Data were extracted from the EUCLID5 data base. Patients were split in 2 groups (HD and OL-HDF) and compared as whole group or matched patients for fluid status criteria including predialysis relative fluid overload (RelFO%) status from the BCM®.Results2242 patients (age 71 years; female: 39%; vintage: 38 months; Charlson index: 6) were studied. 58% of the cohort were prescribed post-dilution OL-HDF. Comparing the HD and OL-HDF groups, there was no difference between HD and OL-HDF patients regarding the predialysis systolic BP, the interdialytic weight gain, the dialysate-plasma sodium gradient, and the predialysis RelFO%. The stepwise logistic regression did not find dialysis modality (HD or OL-HDF) associated with fluid overload or high predialysis systolic blood pressure. In OL-HDF patients, monthly average convective or weekly infusion volumes per session were not related with the presence of fluid overload.ConclusionsIn this cross-sectional study we did not find association between the use of post-dilution OL-HDF and markers of fluid volume excess. Aligned dialysis fluid sodium concentrations to patient predialysis plasma sodium and regular monitoring of fluid volume status by bioimpedance spectroscopy may have been helpful to manage adequately the fluid status in both OL-HDF and HD patients.

Improved Survival of Incident Patients with High-Volume Haemodiafiltration: A Propensity-Matched Cohort Study with Inverse Probability of Censoring Weighting

Background: Haemodiafiltration (HDF) is the preferred dialysis modality in many countries. The aim of the study was to compare the survival of incident patients on high-volume HDF (HV-HDF) with high-flux haemodialysis (HD) in a large-scale European dialysis population. Methods: The study population was extracted from 47,979 patients in 369 NephroCare centres throughout 12 countries. Baseline was six months after dialysis initiation; maximum follow-up was 5 years. Patients were either on HV-HDF (defined as with ≥21 litres substitution fluid volume per session) or on HD if on that treatment for ≥75% of the 3 months before baseline. The main predictor was treatment modality. Other parameters included country, age, gender, BMI, haemoglobin, albumin and Charlson comorbidity index. Propensity score matching and Inverse Probability of Censoring Weighting (IPCW) were applied to reduce bias by indication and consider modality crossover, respectively. Results: After propensity score matching, 1,590 incident patients remained. Kaplan-Meier and proportional Cox regression analyses revealed no significant survival advantage of HV-HDF. Results were biased by modality crossover: during the 5-year study period, 7% of HV-HDF patients switched to HD, and 55% of HD patients switched to HV-HDF. IPCW uncovered a statistically significant survival advantage of HV-HDF (OR 0.501; CI 0.366-0.684; p < 0.001). A higher benefit of HV-HDF for some subgroups was revealed, for example, non-diabetics, patients 65-74 years, patients with obesity or high blood pressure. Conclusions: This large-scale study supports the generalizability of previous RCT findings regarding the survival benefit of HV-HDF. Sub-group analysis showed that some sub-cohorts appear to benefit more from HV-HDF than others.

Survival of incident patients on high-volume online hemodiafiltration compared to low-volume online hemodiafiltration and high-flux hemodialysis

Hemodiafiltration is becoming a preferred treatment modality for dialysis patients in many countries. The volume of substitution fluid delivered has been indicated as an independent mortality risk factor. The aim of this study is to compare patient survival on three different treatment modalities: high-flux hemodialysis, low-volume online HDF (oHDF) and high-volume oHDF. Incident hemodialysis and oHDF patients treated in 13 NephroCare centers in Bosnia and Herzegovina, Serbia and Slovenia between January 1, 2007, and December 31, 2011, were included in this epidemiological cohort study. High-volume oHDF was defined as substitution volume higher than the median substitution volume infused, otherwise low-volume. Main predictor was treatment modality at baseline and in time-dependent model. Other predictors were age, gender, diabetes mellitus, cerebrovascular accident, arrhythmia, hemoglobin and C-reactive protein. Four hundred and forty-two patients were included in the study. Median substitution fluid volume was 20.4 L. Mean difference between the oHDF groups in substitution fluid volume was 8.3 ± 5.2 L [95 % confidence intervals (95 % CI) 7.1-9.5, p < 0.0001]. The unadjusted hazard ratios (HR) with 95 % CI compared to high-flux HD were 0.87 (0.5-1.5) for low-volume oHDF and 0.29 (0.13-0.63) for high-volume oHDF. After the adjustment for covariates, the HR for patients on low-volume oHDF remained statistically insignificant compared to high-flux HD (0.84; 95 % CI 0.46-1.53), while patients on high-volume oHDF showed a marked and significantly lower HR (0.29; 95 % CI 0.13-0.68) than patients on high-flux HD in baseline model. While this effect failed to reach significance in the time-dependent model (HR 0.477; 95 % CI 0.196-1.161), possibly due to an inadequate sample size here, the consistency of results in both models supports the robustness of the findings. After switching from high-flux hemodialysis to oHDF, mean hemoglobin and albumin levels did not change significantly. Mean erythropoietin resistance index (ERI) and erythropoiesis stimulating agents (ESA) consumption decreased significantly (p = 0.02, p = 0.03, respectively). The median substitution volume used in these three countries for post-dilutional oHDF is 20.4 L. oHDF is associated with significant reductions in ERI and ESA consumption. Only high-volume oHDF is associated with improved survival compared to high-flux hemodialysis.

Clinical Audit Improves Hypertension Control in Hemodialysis Patients

In patients on hemodialysis (HD), hypertension is a risk factor for cardiovascular disease. In this study we tested the effectiveness of a clinical audit in improving blood pressure (BP) control in HD patients. 177 adult, prevalent patients undergoing dialysis in NephroCare centers in Italy were audited. At the conclusion of the audit, individual strategies were developed in order to improve BP control. Patient data was collected and examined at months -1 (Pre), 0 (the date of the audit- Audit), and +1 and +6 after the audit (Post-1 and Post-6, respectively). We recorded BP, information on factors affecting BP, and anti-hypertensive drug regimen. The primary outcome of the study was to decrease prevalence of hypertension (BP ≥ 140/90 mmHg). Secondary outcomes were a reduction in average BP in hypertensive patients and/or a decrease in drug delivery associated with lower or unchanged BP. 104 patients out of 177 (58.7%) were hypertensive at Audit. BP levels were directly related to comorbidity and male sex, and inversely related to dialysate sodium concentration. The announcement of the audit alone was associated with a decreased prevalence of hypertension (Pre 64.4% to Audit 58.7%); a further decrease followed the audit (Post-1 51.1%, Post-6 47.6%, p<0.05 vs. Audit). Systolic BP in hypertensive patients also decreased (mean decrease was -8.5 and -14.1; p = 0.007 and p<0.001 at Post-1 and Post-6). Number of drugs assumed was significantly lower at Post-1 and Post-6 vs. Audit (p = 0.005 and p<0.001, respectively). A clinical audit is an effective tool to improve BP control in HD patients.