Jayanthy Ramesh, Mohammad Ibrahim Shaik and Jayanthy Srivalli
Objective: To elucidate how iron deficiency anemia influence the natural history of diabetes mellitus and to study the effect of iron indices, mitochondrial oxidative capacity and oxidative stress on insulin resistance and secretion in established cases of type 2 diabetes.
Research design and methods: A comparative cross-sectional study was conducted in 40 healthy controls, 40 iron deficiency anemia (IDA), 40 type 2 diabetes without iron deficiency anemia and 40 type 2 diabetes with iron deficiency patients. All the Patients were BMI, age and sex matched. Glycemic indices, fasting serum insulin levels, iron indices, inflammatory markers, Total Antioxidation Capacity (TAOC), Mitochondrial Oxidative Capacity (MOC) were analyzed.
Results: In iron deficiency anemia there was decrease in MOC, TAOC and HOMA B (p<0.001). Iron was positively correlated with MOC which in turn was positively correlated with HOMA B. In type 2 diabetes there was increase in free iron, ferritin, transferrin, TNF-alpha and HOMA IR (p<0.001) and decrease in TAOC, MOC and HOMA B. In type 2 diabetes with IDA there was decrease in iron, ferritin HOMA-IR (p<0.001), TNF- α (p<0.05) and increase in IL-6(p<0.05) as compared to type 2 diabetes without IDA.
Conclusion: Iron deficiency anemia is associated with decreased mitochondrial oxidative capacity and insulin secretion with no change in insulin sensitivity. This prompts us to question whether chronic IDA predisposes to early development of diabetes especially where both diabetes and IDA are highly prevalent. Both diabetes and iron deficiency anemia can together worsen the oxidative stress and the pathophysiology of diabetes mellitus despite improvement in insulin resistance.