Iron Deficiency Anemia- Does it affect the Glycosylated Hemoglobin levels in Non- diabetic Patients?

Background: Glycosylated hemo?globin (HbA1c) is used in diabetic patients as an index of glycemic control. Reports on the effects of iron deficien?cy anemia (IDA) on HbA1c levels have shown inconsistent results. This study investigated the effects of IDA on HbA1c levels in non- diabetic patients. Methods: Fifty non- diabetic patients diagnosed as having IDA, and an equal number of age- and sex- matched healthy controls, were included in this study. Hematological and biochemical parameters, including HbA1c levels were measured, and compared between cases and controls. Results: Mean baseline HbA1c (%) level in anemic patients (6.1 ± 0.2) was significantly higher than in control group (4.1 ± 0.3) (p < 0.0001, 95% CI 1.89 to 2.1). A significant positive correlation of HbA1c was observed with total iron binding capacity (TIBC) (r = 0.36, p = 0.009, 95 % CI 0.09 to 0.58), but not with hemoglobin (r = −0.015, p = 0.915, 95% CI −0.29 to 0.26), MCV (r = −0.082, p = 0.571, 95 % CI −0.35 to 0.20), MCH (r = −0.11, p = 0.453, 95% CI −0.38 to 0.18), hematocrit (r = −0.0032, p = 0.982, 95% CI −0.28 to 0.28) and ferritin (r = −0.052 p = 0.721, 95% CI −0.33 to 0.23). Conclusions: HbA1c levels were higher in patients with IDA than in controls and had a significant positive correlation with TIBC. This may have a practical application in diabetic individuals with IDA where HbA1c alone may give a false picture of poor glycemic control