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

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.