The effect of the erythropoietin resistance index on brain hemorrhage and infarction risk in maintenance hemodialysis patients: a retrospective cohort study.

Background: Maintenance hemodialysis (MHD) is the main renal replacement therapy for patients with end-stage renal disease, and erythropoietin (EPO) is the main therapy for renal anemia in patients receiving maintenance hemodialysis. However, the risks of brain hemorrhage and infarction in patients on hemodialysis with erythropoietin therapy remain unclear. Methods: Patients who underwent regular hemodialysis at the Blood Purification Center of the Northern Theater General Hospital from January 1, 2018, to January 1, 2022, were retrospectively selected. A total of 588 MHD patients were enrolled on the basis of the inclusion and exclusion criteria. The primary endpoint of follow-up was brain hemorrhage and infarction, or January 1, 2024. The secondary endpoint was all-cause death. The erythropoietin resistance index (ERI) was calculated as follows: erythropoiesis-stimulating agent (ESA) (IU/week)/body weight (kg)/hemoglobin level (g/dL). Patients were divided into four groups according to ERI quartile, and a Cox proportional risk model was applied to observe the associations between the ERI and the risks of brain hemorrhage and infarction and all-cause mortality. Results: During a median follow-up of 6 years, brain hemorrhage events occurred in 41 (6.9%) MHD patients, and brain infarction events occurred in 61 (10.3%) MHD patients. According to the Kaplan-Meier curve, the incidence of brain hemorrhage and infarction was greater in the high-ERI subgroup than in the low-ERI subgroup (p < 0.001). Multivariate Cox regression analysis revealed that a high ERI was a significant predictor of brain hemorrhage (HR: 3.85, 95% CI [1.34-11.07], p = 0.012) and brain infarction (HR = 2.657, 95% CI [1.17-6.02], p = 0.020). A higher ERI was associated with an increased risk of all-cause death in MHD patients (HR: 1.72, 95% CI [1.05-2.82], p = 0.033). Conclusions: Higher ERI scores were associated with brain hemorrhage and infarction in MHD patients.