Increased serum ferritin in insulin-dependent diabetes mellitus: relation to glycemic control

Iron supplement in pregnancy and development of gestational diabetes—a randomised placebo‐controlled trial

“…Cross-sectional studies suggested that raised serum ferritin levels were found in women with noninsulin dependent diabetes as well as in women with gestational diabetes mellitus (GDM), and it was reported to be associated with glycaemic control. [8][9][10][11][12] These findings were supported by large-population-based studies where elevated ferritin levels were associated with increased risk of development of type 2 DM as well as GDM. [13][14][15] Furthermore, data from population-based prospective cohort studies have shown that those with higher serum ferritin levels or iron intake were at increased risk of developing diabetes during a 10-to 11-year follow-up period.…”

Gestational diabetes mellitus in the last trimester – a feature of maternal iron excess?

“…In the non‐pregnant non‐diabetic population, ferritin concentration correlates with glucose, insulin, fructosamine, and lipids[19,28], and this correlation remains significant even after correcting for BMI[19]. In non‐pregnant diabetic subjects, ferritin concentration not only was found to be correlated with HbA 1c [17,18,29], but was also an independent predictor of HbA 1c [19]. Excess iron can affect insulin synthesis and secretion, and enhance oxidation of lipids, especially non‐esterified fatty acids[30], the increased oxidation of which decrease glucose utilization in muscles and increase gluconeogenesis in liver leading to liver mediated insulin resistance[30].…”

“…Liver‐mediated insulin resistance could also be related to iron accumulation in hepatocytes with impaired hepatic insulin extraction[31]. However, modest increase in body iron does not affect insulin secretion[28], and the increased ferritin in poorly controlled diabetic subjects could be markedly decreased with short‐term improvement in diabetic control[17,18]. Furthermore, the earlier report of improved glycaemic control using deferoxamine to normalize raised ferritin concentration in diabetic subjects[15] was not substantiated[16].…”

“…In conditions of iron overload, it has been found that 50% of transfusion‐treated beta thalassaemia patients have abnormal glucose tolerance[12], and up to 65% of patients with hereditary haemochromatosis developed diabetes[13]. However, raised serum ferritin concentration could also be found in diabetic subjects without haemochromatosis or multiple transfusions[14,15,16,17,18]. Furthermore, it has been suggested recently that an elevated ferritin concentration is part of the picture of insulin resistance, as it was correlated with the glucose area under the curve in normal subjects, and was also an independent predictor of HbA 1c in non‐insulin dependent diabetic subjects[19].…”