Abstract
Objective: To determine factors that could predict a higher erythropoiesis resistive index (ERI) in patients on maintenance hemodialysis.
Methodology: This observational study was carried out at the Department of Nephrology, Combined Military Hospital, Lahore from September to October 2024. Patients on maintenance hemodialysis for the last three months or more were included. Patients with acute kidney injury, patients with chronic kidney disease undergoing maintenance hemodialysis for less than three months, patients frequently missing their hemodialysis sessions to an extent that they get dialyzed less than two times a week were excluded. Information about the type of vascular access, frequency and vintage of hemodialysis, presence of residual renal function (defined as urine output >100 ml/ day), and the total weekly erythropoietin dose being administered were recorded. Charlston Comorbidity Index was calculated. Hemoglobin and serum albumin levels were checked pre-dialysis. Kt/V was measured using the built-in online clearance monitoring module.
Results: There were 92 patients, aged 54.32±13.81 years. Adequate hemoglobin levels (>10 g/dL) were attained in only 33 (35.87%) patients. The median ERI was 16.26 IU/week/kg/g/dL, with an interquartile range from 12.21- 20.39. It was <10 IU/week/kg/g/dL in 10 (10.87%) patients only. Loss of residual renal function predicted a higher ERI (Odds ratio: 2.541; 95% confidence interval=1.043, 6.194; p=0.040). Age, gender, hemodialysis vintage, frequency or vintage of hemodialysis, vascular access, comorbidities, Kt/V and serum albumin were insignificant in this regard.
Conclusion: Loss of residual renal function is associated with a higher erythropoiesis resistive index.

Key words: Anemia, chronic kidney failure, end stage renal disease, erythropoietin, renal dialysis.