Clinical Nutrition Department, Division of Traditional Chinese Medicine, Second Military Medical University, Shanghai, China.
Am J Clin Nutr. 2011 Oct;94(4):1012-9. doi: 10.3945/ajcn.111.015743. Epub 2011 Aug 31.
Emerging scientific evidence has disclosed a correlation between iron metabolism and type 2 diabetes (T2D).
The objective of this study was to test the hypothesis that body iron stores are higher in a Chinese population with altered glucose homeostasis.
Serum iron, ferritin, and soluble transferrin receptor concentrations were measured in 298 subjects, including 70 subjects with normal glucose tolerance (NGT group), 60 subjects with prediabetes (prediabetes group), and 168 subjects with T2D (T2D group). Hepatic iron stores in 88 subjects were assessed by using a magnetic resonance imaging (MRI) T2* gradient-recalled-echo technique. A general linear model ANOVA was performed for comparisons between groups after adjustment for age and BMI. Stepwise multiple linear regression analysis was used to identify factors associated with the MRI-estimated hepatic iron concentration (M-HIC).
Mean (±SD) M-HIC and R2* values in the prediabetes and T2D groups were significantly higher than in the NGT group (M-HIC: 40.6 ± 8.6 and 39.3 ± 10.7 μmol/g compared with 27.8 ± 9.1 μmol/g; R2* values: 47.9 ± 11.9 and 47.3 ± 11.5 s(-1) compared with 34.9 ± 7.0 s(-1); all P < 0.01). No significant difference was shown in M-HIC and R2* values between prediabetes and T2D groups. The M-HIC independently contributed to 43.3% of the glycated hemoglobin variance after adjustment for main clinical indexes (P < 0.001). The proportions of subjects with mild hepatic iron overload in the NGT, prediabetes, and T2D groups were 12.5%, 70.6%, and 63.6%, respectively.
To our knowledge, our findings provide novel evidence to support the hypothesis of a mild iron overload in patients with prediabetes and T2D. A cohort study concerned with the effect of the attenuation of excess iron on glucose metabolism in a prediabetic population is warranted.
新兴的科学证据揭示了铁代谢与 2 型糖尿病（T2D）之间的关联。
本研究旨在检验以下假设，即糖代谢异常的中国人群体内铁储存量更高。
本研究共纳入 298 名受试者，包括 70 名糖耐量正常（NGT 组）、60 名糖尿病前期（糖尿病前期组）和 168 名 2 型糖尿病（T2D 组）患者。采用磁共振成像（MRI）T2*梯度回波技术评估 88 名受试者的肝铁含量。对各组数据进行年龄和 BMI 校正后，采用一般线性模型方差分析进行比较。采用逐步多元线性回归分析确定与 MRI 估计肝铁浓度（M-HIC）相关的因素。
糖尿病前期和 T2D 组的平均（±SD）M-HIC 和 R2值明显高于 NGT 组（M-HIC：40.6 ± 8.6 和 39.3 ± 10.7 μmol/g 比 27.8 ± 9.1 μmol/g；R2值：47.9 ± 11.9 和 47.3 ± 11.5 s(-1) 比 34.9 ± 7.0 s(-1)；均 P < 0.01）。糖尿病前期和 T2D 组间 M-HIC 和 R2*值无显著差异。在校正主要临床指标后，M-HIC 可独立解释糖化血红蛋白变异的 43.3%（P < 0.001）。NGT、糖尿病前期和 T2D 组中轻度肝铁过载的受试者比例分别为 12.5%、70.6%和 63.6%。
据我们所知，本研究结果为糖尿病前期和 T2D 患者存在轻度铁过载的假设提供了新的证据。有必要进行一项队列研究，关注在糖尿病前期人群中减少过量铁对葡萄糖代谢的影响。
