Assessing the Impact of Inflammation on Erythropoietin Resistance in Hemodialysis: The Role of the NLR.

The neutrophil-to-lymphocyte ratio (NLR) has emerged as a readily available marker of systemic inflammation and immune dysregulation. In patients undergoing hemodialysis, inflammation is a known contributor to erythropoietin resistance. However, the relationship between the NLR and the erythropoietin resistance index (ERI) has not been extensively characterized. A total of 317 hemodialysis patients were retrospectively evaluated and stratified into tertiles based on NLR levels. Biochemical, inflammatory, and anthropometric variables were compared across groups. Spearman's rank correlation was used to assess the relationship between the NLR and the ERI. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive ability of the NLR for erythropoietin resistance, defined as ERI > 10. Subsequently, linear and logistic regression models were employed to examine the independent association between the NLR and the ERI, adjusting for relevant covariates. Higher NLR tertiles were significantly associated with increased CRP, lower serum iron, and elevated ERI ( = 0.002). Spearman's analysis revealed a modest but significant correlation between the NLR and the ERI (ρ = 0.31, < 0.0001). ROC analysis identified an NLR threshold of 4.4 for detecting ERI > 10. In multivariable analysis, the NLR was independently associated with the ERI both as a continuous variable (β = 0.848, = 0.046) and as a binary outcome (OR = 1.22, 95% CI: 0.95-1.24, = 0.0021), while serum iron and hemoglobin also emerged as significant predictors. In this cohort of hemodialysis patients, a higher NLR was independently associated with increased erythropoietin resistance, suggesting its potential utility as an accessible inflammatory biomarker in anemia management. These findings add to the limited but growing body of evidence supporting the prognostic role of the NLR in dialysis populations and warrant further validation in prospective studies.