OBJECTIVE

Data on the association between body iron and glucose homeostasis by the three glycemic states are scarce. Thus, we investigated the association between body iron as assessed by serum ferritin (sF) concentration and glucose homeostasis using homeostasis model assessment of insulin resistance (HOMA-IR) and beta cell function (HOMA-BcF) in different glycemic states.

METHODS

A cross-sectional analysis was conducted in 2,541 men aged 42-60 years in 1984-1989, in the Kuopio Ischemic Heart Disease Risk Factor Study. Subjects were classified into the three glycemic states, normoglycemia, prediabetes and type 2 diabetes (T2D), by fasting plasma glucose measurements and the information collected at study visit. The association between sF quartiles and HOMA-IR and HOMA-BcF for each glycemic state was examined by analysis of covariance and linear regression analysis.

RESULTS

The mean age and sF concentrations were 53.1?years (S.D. 5.7, range 42.0-61.3?years) and 166.2?µg/L (S.D. 141.7, range, 11-960?µg/L), respectively. After multivariable adjustments, a weak direct association was observed between sF quartiles and HOMA-IR in normoglycemia (P-trend?=?0.001), but a direct association in prediabetes (P-trend?=?0.007) and in T2D (P-trend?=?0.078). In HOMA-BcF, the association was weak direct in normoglycemia (P-trend?=?0.003), direct in prediabetes (P-trend?=?0.005), and inverse in T2D (P-trend?=?0.105). Strongest associations were observed in prediabetes (??=?0.25, 95%CI?=?0.14-0.36, P?=?0.004, in HOMA-IR; ??=?0.23, 95%CI?=?0.15-0.31, P?=?0.008, in HOMA-BcF) after 100?µg/L increase in sF (log-transformed).

CONCLUSIONS

These data suggest that both the strength and the direction of the association between body iron stores and glucose homeostasis are dependent on the glycemic state of the population. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.