Liver Iron Stores in Patients With Non-Insulin-Dependent Diabetes Mellitus

Iron overload such as that in idiopathic hemochromatosis is a well-established, albeit rare, cause of non-insulin-dependent diabetes mellitus (NIDDM). Most patients with NIDDM have no recognized cause of their disease. Investigators have proposed that subclinical iron overload may cause diabetes mellitus in a substantial number of patients with NIDDM. The aim of the current study was to evaluate hepatic iron stores in autopsy specimens from a group of community residents with NEDDM. Fifteen patients with NIDDM and 17 age-matched control subjects were identified from a review of medical records of deceased residents of Olmsted County, Minnesota. Formalin-fixed liver tissue was analyzed for iron concentration by flameless atomic absorption spectrophotometry, and distribution of hepatic iron was determined histochemically. No significant difference was found in either the distribution or the mean amount of hepatic iron between the diabetic and the control group (1,303 versus 1,349 μg Fe/g dry weight; P = 0.87). Thus, the mean difference was −46 μg Fe/g dry weight (confidence interval, −631 to 540). Because hepatic iron quantification is the definitive means of assessing total body iron stores, our results suggest that NIDDM is typically not associated with a substantial level of iron overload.