Influence of Iron Deficiency Anemia on Hemoglobin A1C

Glycated hemoglobin (HbA1c) is the predominant fraction of hemoglobin A1(HbA1), and it constitutes 5% of the total Hg in normal adults and up to15% in patients with diabetes mellitus (DM). It is used as a clinical indicator of the blood sugar level of an individual during the previous three months. There are several medical conditions that affect and lead to falsely higher or lower values of HbA1c unrelated to diabetes including hemolytic anemias, acute blood loss, iron deficiency (ID), alcoholism, pregnancy, chronic kidney disease and hemoglobinopathies. Several studies reported that reduced iron stores have a link with increased level of HbA1c in the blood leading to false high values of HbA1c. 40 patients with iron deficiency anemia (IDA), their ages ranged from (20 to 50) years old, and 35 cases apparently healthy individuals, their ages were matched with patients were included into the study. Complete blood count (CBC), fasting blood glucose (FBG), serum ferritin, kidney function tests (KFTs), and HbA1c levels were done for all samples. Hemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), hematocrit (HCT), and ferritin were lower in IDA patients than control group, red distribution width (RDW), and platelet (PLT) were increased in IDA patients than control group, patients with IDA had higher HbA1c levels when compared with control group, and there were negative correlations between HbA1c with Hb, MCV, MCH, and ferritin in studied group. Our study proved that patients with IDA had higher values of HbA1c than healthy group, so correction of IDA by iron supplementation should be done before using HbA1c in the diagnosis and monitoring of diabetes.