Effect of Iron Deficiency Anaemia on Hemoglobin A1c (HbA1c) Levels in Diabetic Patients in Tertiary Care Hospita

Background:Diabetes mellitus has become a major health problem worldwide. American diabetes association has considered HbA1c levels < 6.5 % as a targetfor glycemic control and as a diagnostic criterion for diabetes. Anemia is common in diabetes mellitus. Previous studies on alteration of HbA1c in iron deficiency anemia (IDA) have conflicting results. Objective:The primary aim of this study was to identify and compare effect of IDA on HbA1c levels among controlled diabetics (fasting glucose less than 126 mg/dl since last six months) and its variation according to the degree of anemia. Methods:The present study is cross sectional study, including 70 controlled diabetics (35 iron deficiency anemia and 35 without anemia). HbA1c, complete haemogram, iron profile and fasting blood glucose were tested. Medical history was recorded. Results:The mean HbA1c levels in controlled diabetics with and without IDA were 7.94 ±1.45and 6.22 ±0.33respectively (p < 0.05). The mean HbA1c levels in mild and moderate anemia was significantly raised as compared to controls whereas this rise was not found significant. In severe anemia the mean HbA1c was 8.86 ±1.96which was slightly low as compared to moderate grade anemia 8.93 ±2.84. Conclusion:In IDA falsely elevated HbA1c is independent of the blood glucose concentration in controlled diabetics. Hence, prior to alteration of treatment regimen based on HbA1c for diabetes,IDA should be diagnosed and corrected. Concurrent evaluation for anemia is critical to correctly interpret glycemic status in Indian population with prevalent diabetes.