Serum Albumin, eGFR, and Anemia in Patients with Renal Impairment: A Cross-Sectional Study

Abstract

Background: Serum albumin is related with conditions such as malnutrition, inflammation, hematology, and renal impairment; however, the effect of serum albumin independently of eGFR in relation to prediction of anemia in cases with renal impairment is not well established. Objective: The goal is to assess the correlation of albumin in serum and eGFR with hematological status and prediction of anemia in patients with renal impairment. Subjects and Methods: The cross-sectional study consisted of 119 participants with renal dysfunction (age ≥18) and was carried out in March 2026. Tests performed included serum albumin, hemoglobin, packed cell volume (PCV), WBC count, fasting blood sugar (FBS), and creatinine. The eGFR was obtained using the CKD-EPI formula of 2021. The statistical tests included were Spearman correlation, multivariable regression, and ROC curve analysis (using SPSS v26 and confirmed in R) to analyze: (i) albumin alone, (ii) eGFR alone, and (iii) combination of albumin, eGFR, and FBS as a predictor of anemia. Results: Mean albumin was found to be 3.54 ± 0.74 g/dL, while the mean eGFR was 73.5 ± 40.4 mL/min/1.73m²; 37.0% of participants had impaired eGFR level (<60 mL/min/1.73 m²). Albumin was significantly correlated with hemoglobin (r = 0.354), packed cell volume (PCV) (r = 0.339), and eGFR (r = 0.411; p < 0.001 for all). In models adjusting for the effect of eGFR and gender, albumin independently correlated with hemoglobin (β = 0.707; p = 0.015) and PCV (β = 1.630; p = 0.047). As for anemia predictors, significant predictors were identified in eGFR (OR = 0.977; p < 0.001) but not in albumin level (OR = 0.71; p = 0.306). eGFR alone was more predictive than albumin with regard to anemia (AUC = 0.733 vs 0.633); The further combination of the two in a combined model provided only small incremental benefit (AUC = 0.738). Conclusion: The direct calculation of eGFR from serum creatinine level, age, and gender proves itself as the main indicator in connection with anemia and kidney dysfunction. Albumin shows its relationship independently with hemoglobin and PCV, but lacks predictive power alone regarding anemia once the calculation of eGFR is taken into consideration.