A study on influence of iron deficiency anaemia over HbA1c levels


  • Sankar Kalairajan Department of General Medicine, ESIC Medical College and PGIMSR, K. K. Nagar, Chennai, Tamil Nadu, India
  • Vijaya Durairaj K. Department of General Medicine, ESIC Medical College and PGIMSR, K. K. Nagar, Chennai, Tamil Nadu, India
  • Malathy A. R. Department of General Medicine, ESIC Medical College and PGIMSR, K. K. Nagar, Chennai, Tamil Nadu, India




Diabetes, Glycated haemoglobin, Haemoglobin A1c, HbA1c, IDA, Iron deficiency anaemia


Background: Haemoglobin A1c (HbA1c) is a glycated form of haemoglobin reflects average plasma glucose over the previous 8 to 12 weeks. HbA1c can be affected by multiple non-glycaemic parameters. Iron deficiency anaemia (IDA) is one among them which is the most common type of anaemia in India. However, reports on the effects of iron deficiency anaemia on HbA1c levels are inconsistent. Hence we conducted a study to find out the influence of iron deficiency anaemia over HbA1c levels.  

Methods: 120 patients confirmed to have iron deficiency anaemia were enrolled in this study. HbA1c levels were measured at baseline and 3 months after treatment, and these values were compared with those in the control population.

Results: The mean baseline HbA1c level in anaemic patients (4.62%) was significantly lower than that in the control group (5.45%, P<0.001). A significant increase was observed in the patients HbA1c levels at 3 months after treatment (5.82%, P<0.001). There was a significant correlation observed between haemoglobin and HbA1c level (Coefficient of correlation=0.26, P<0.01) in the study group before correction.

Conclusions: In contrast to the observations of previous studies, ours showed that HbA1c levels increased with treatment of iron deficiency anaemia. This could be attributable to nutritional deficiency, racial-ethnic variations and/or certain unknown variables. Further studies are warranted.


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