Serum ferritin tied to type 2 diabetes risk

A high serum concentration of ferritin is a risk factor for type 2 diabetes, reports a new meta-analysis.

Searching the databases of PubMed and Embase, investigators retrieved 12 case-control and cohort studies, corresponding to 6,515 patients and 43,120 controls without the condition. Only those that assessed the effects of iron metabolism indicators―such as iron, ferritin, hepcidin, and transferrin and its soluble receptor―on type 2 diabetes risk were eligible.

Eleven studies were available for describing the relationship between ferritin and type 2 diabetes. Pooled analysis revealed that medium serum ferritin concentration was a significant risk factor (odds ratio [OR], 1.20, 95 percent confidence interval, 1.08–1.33) for type 2 diabetes, as were high levels (OR, 1.43, 95 percent CI, 1.29–1.59).

Low serum ferritin, on the other hand, showed no such effect (OR, 0.99, 95 percent CI, 0.89–1.11). These ferritin categories were based on cutoffs employed in eight of the 11 studies. Findings were robust to sensitivity analyses.

In comparison, pooled analysis of three studies revealed that the soluble transferrin receptor was not a significant indicator of type 2 diabetes, regardless of alterations in serum concentrations, nor was the ratio between the soluble transferrin receptor and ferritin. There were not enough studies on hepcidin and transferrin, in relation to type 2 diabetes risk, to warrant a meta-analysis.

However, “[a] systematic review showed that serum transferrin and hepcidin may be directly or indirectly related to the development of diabetes,” said researchers.