Estimation of mean erythrocyte age using HbA1c or HbA1c/glycated albumin for evaluation of anemia severity

Abstract Background Hemoglobin A1c (HbA1c) levels are low in patients with hemolytic anemia, as HbA1c reflects mean erythrocyte age (M RBC ). Erythrocyte creatine (EC) is a hemolytic indicator that also reflects M RBC . We previously reported an equation for estimating M RBC using EC (EC‐M RBC ). Aims In this study, EC‐M RBC was compared to the HbA1c level expressed in the International Federation of Clinical Chemistry and Laboratory Medicine units (iA1c) and to the iA1c/glycated albumin (GA) ratio to estimate M RBC . Methods This study included 238 subjects, including patients with hemolytic anemia and/or type 2 diabetes mellitus (T2DM). Results In non‐diabetic individuals, both iA1c and iA1c/GA showed a strong positive correlation with EC‐M RBC ( p < 0.0001). The equations to estimate iA1c‐M RBC and iA1c/GA‐M RBC derived from the regression equations between EC‐M RBC and iA1c, and EC‐M RBC and iA1c/GA in nondiabetic individuals were 1.45 × iA1c and 20.0 × iA1c/GA, respectively. iA1c‐MRBC and iA1c/GA‐MRBC in non‐diabetic individuals without hemolytic anemia were 57.6 ± 4.0 and 57.1 ± 6.4 days, respectively, and iA1c/GA‐MRBC in T2DM patients without hemolytic anemia was 56.0 ± 8.8 days.; no significant difference was seen in the comparisons. Conclusions The M RBC can be estimated using iA1c or iA1c/GA in non‐diabetic individuals, and iA1c/GA in T2DM patients.