Relationship between anti-erythropoietin receptor autoantibodies and responsiveness to erythropoiesis-stimulating agents in patients on hemodialysis: a multi-center cross-sectional study

Synergistic deterioration of prognosis associated with decreased grip strength and hyporesponse to erythropoiesis-stimulating agents in patients undergoing hemodialysis

Introduction

We examined the combined effect of erythropoietin (EPO) hyporesponsiveness and low handgrip strength (HGS) on the prognosis of patients undergoing hemodialysis (HD).

Methods

We recruited patients with chronic kidney disease (CKD) Stage 5, who were undergoing HD at our dialysis clinic between January 2015 and March 2015 (n = 182). Patients of ≥20 years of age and who had been undergoing HD for ≧3 months at enrollment were eligible for inclusion. Seven patients treated with epoetin-β pegol were excluded. First, the erythropoietin resistance index (ERI) and HGS were measured. The patients were stratified by the ERI of 9.44 (U/kg/week/g/dL), and by the HGS of 28 kg for men and 18 kg for women. We then observed death and cardiovascular disease (CVD), composite endpoint (deaths or CVD) for a median of 2 years.

Results

A total of 175 patients (male, n = 122; female, n = 53; age, 34–92 years) were included in the analysis. During the observation period of 24 months, 57 events (14 deaths and 43 CVD) were observed. High ERI and low HGS were associated with a high incidence of endpoints compared to low ERI and high HGS. Among the four groups classified by ERI and HGS values, the highest risk group was the high ERI/low HGS group (HR: 4.20 95% CI 2.12–8.33).

Conclusions

EPO hyporesponsiveness combined with low HGS were found to be significant predictors of a poor outcome, and the synergistic effects of the two factors had stronger predictive ability than either single factor.

Parathyroidectomy Improves the Consumption of Erythropoiesis-Stimulating Agents in Hemodialysis Patients

Secondary hyperparathyroidism (SHPT) is common in end-stage renal disease (ESRD) patients, and it can suppress erythropoiesis. We aimed to investigate the relationship between the consumption of erythropoiesis-stimulating agents (ESAs) and parathyroidectomy (PTX) in ESRD patients with SHPT and to determine the predictors for anemia improvement. The current standard of chronic kidney disease anemia therapy relies on the prescription of iron supplementation, and ESA. We retrospectively analyzed 81 ESRD patients with PTX at Ditmanson Medical Foundation Chiayi Christian Hospital from July 2004 to Dec 2018. The requirement of ESA therapy markedly declined from a dose of 41.6 (interquartile range [IQR], 0−91.2) to 10.3 (IQR, 0−59.5, p = 0.001) unit/kg/week. In addition, 63.7% of patients required iron replacement therapy preoperatively and the proportion reduced to 52.5% after PTX (p < 0.001). The hemoglobin (Hb) level showed an insignificant change from a median value of 10.7 g/dL (9.5−11.6 g/dL) before PTX to 10.5 g/dL (9.6−11.2 g/dL) at 6 months after PTX. A preoperative Hb level ≤ 10 mg/dL (odds ratio [OR], 20.1; 95% confidence interval [CI], 4.71−125, p < 0.001) and transferrin saturation (TSAT) < 25% (OR, 12.8; 95% CI, 2.51−129, p < 0.001) were predictors for anemia improvement. Our study demonstrated that PTX markedly decreased the requirement of ESA. Patients with a low preoperative Hb level or low TSAT showed an increase in the Hb level after PTX. PTX may be considered not only for SHPT with refractory anemia but also for high ESA-dependent patients.

Association between Anti-Erythropoietin Receptor Antibodies and Cardiac Function in Patients on Hemodialysis: A Multicenter Cross-Sectional Study

Cardiac dysfunction is an important prognostic predictor of cardiovascular mortality in patients on hemodialysis (HD). Erythropoietin (EPO) has been reported to improve cardiac function by binding to the EPO receptor (EPOR) on cardiomyocytes. This study investigated whether anti-EPOR antibodies were associated with left ventricular cardiac function in patients undergoing HD. This multicenter, cross-sectional observational study included 377 patients (median age, 70 years; 267 (70.8%) males) with chronic kidney disease (CKD) undergoing stable maintenance HD. Serum levels of anti-EPOR antibodies were measured, and echocardiography was used to assess the left ventricular mass index (LVMI) and left ventricular ejection fraction (LVEF). Anti-EPOR antibodies were found in 17 patients (4.5%). LVMI was greater (median of 135 g/m2 vs. 115 g/m2, p = 0.042), and the prevalence of LVEF < 50% was higher (35.3% vs. 15.6%, p = 0.032) in patients with anti-EPOR antibodies than in those without. Multivariable linear regression and logistic regression analysis (after adjusting for known risk factors of heart failure) revealed that anti-EPOR antibodies were independently associated with LVMI (coefficient 16.2%; 95% confidence interval (CI) 1.0−35.0%, p = 0.043) and LVEF <50% (odds ratio 3.20; 95% CI 1.05−9.73, p = 0.041). Thus, anti-EPOR antibody positivity was associated with left ventricular dysfunction in patients undergoing HD.

A Prospective, Self-Controlled Pilot Study of the Efficacy of Roxadustat for Erythropoietin Hyporesponsiveness in Patients Requiring Chronic Ambulatory Peritoneal Dialysis

OBJECTIVES

The present study aimed to explore the efficacy and safety of roxadustat in patients with renal anemia and erythropoietin (EPO) hyporesponsive who are receiving continuous ambulatory peritoneal dialysis (CAPD).

METHODS

This is a single center, before and after treatment, self-controlled study; 55 CAPD patients with renal anemia and EPO hyporesponsiveness were enrolled. The main follow-up parameters included routine blood, liver and kidney function, electrolyte, blood lipid, high-sensitivity C-reactive protein, and iron tests. Serum samples were used to determine interleukin-6 and tumor necrosis factor-α levels via enzyme linked immunosorbent assay. The Modified Quantitative Subjective Global Assessment Score and Malnutrition-Inflammation Score before and after treatment, and adverse events during treatment were recorded. The follow-up observation time was 12 weeks. Preliminary data 12-24 weeks before the enrollment as well as post-follow-up data at 36 weeks were also collected.

RESULTS

Fifty patients completed the 12-week follow-up. The hemoglobin levels were 8.0 ± 1.2 g/dL at baseline and 11.2 ± 2.0 g/dL after 12 weeks of roxadustat treatment. The hemoglobin increases at all measured time points and was statistically significant compared with the baseline value (P < .05). The overall hemoglobin response rate (hemoglobin increase ≥ 1.0 g/dL) was 80%, and 50% of the patients reached the hemoglobin target (hemoglobin ≥ 11.0 g/dL) at 12 weeks. Transferrin was higher at 12 weeks (2.2 ± 0.5 g/L) than at baseline (1.7 ± 0.5 g/L) (P < .05), while serum ferritin levels slightly decreased compared with the baseline value (P > .05). The median high-sensitivity C-reactive protein level and other inflammation-related indicators, such as white blood cell counts, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, interleukin-6, and tumor necrosis factor-α, were not significantly different from their baseline values. Nutrition-related biochemical indices such as albumin, creatinine, and blood lipids were also not significantly changed. The Modified Quantitative Subjective Global Assessment Score and Malnutrition-Inflammation Score were slightly lower at 12 weeks than at baseline. No serious adverse events were observed during the follow-up period. Post-follow-up data revealed a maintained hemoglobin level in patients who remained on roxadustat treatment while those switched back to EPO treatment after 12 weeks resulted in a decreased hemoglobin at 36 weeks.

CONCLUSIONS

In patients with EPO hyporesponsiveness on CAPD, roxadustat can efficiently and safely improve anemia and nutritional status without promoting inflammation.

Association of mineral metabolism biomarkers with chronic kidney disease in Chinese adults

Background

We aimed to examine the association of three mineral metabolism markers, including serum calcium, inorganic phosphorus, and intact parathyroid hormone with the risk of chronic kidney disease (CKD) at all stages.

Methods

This retrospective cohort study involved 3563 participants, including 3274 CKD patients and 289 healthy controls. CKD is diagnosed according to clinical guidelines from the 2012 KDIGO. Effect sizes are expressed odds ratio (OR) and 95 confidence interval (CI).

Results

After propensity score matching, per 0.5 mg/dL increment of inorganic phosphorus was significantly associated with 1.33-, 1.61-, and 2.85-fold increased risk of CKD at stages 1–2, 4, and 5, respectively. Regarding per 8 pg/mL increment of intact parathyroid hormone, significance was only noted for stage 5. In subsidiary analyses, the risk prediction of mineral metabolism markers under study was more evident in males and hypertensive subjects. A nomogram prediction model was constructed based on age, sex, and three mineral metabolism markers for CKD, with decent accuracy.

Conclusions

Our findings indicate that serum calcium was associated with all-stage CKD risk, whereas the association for inorganic phosphorus and intact parathyroid hormone was significant at advanced stages.