Diabetes Care:代谢综合征可发生大脑白质改变

　　来自日本的一项研究表明，代谢综合征患者可发生脑白质的微结构变化。其中，各向异性分数（FA）值可能是评价​​代谢综合征患者白质改变的有价值指标。研究在2012年11月19日在线发表于《糖尿病护理》（Diabetes Care）杂志。

　　该研究旨在评价代谢综合征患者白质变化的区域表型。此外，研究还探讨了白质的改变是否与体质指数（BMI）相关。

　　研究共纳入7例患有代谢综合征的中年男性受试者及7例无代谢综合征的中年男性受试者，应用3T磁共振成像设备对受试者进行弥散张量成像。研究采用基于纤维束示踪的空间统计分析（Tract-Based Spatial Statistics，TBSS）方法（全脑分析），分析了各向异性分数（FA）值。其后，采用示踪特异性分析（脑区域分析），测量评价了所有受试者右下额叶-枕叶束（IFOF）的平均FA值。使用Pearson相关系数，评估右下额叶-枕叶束平均FA值和BMI之间的关系。

　　全脑分析结果表明，患有代谢综合征受试者的较对照组表现为显著降低的FA值，出现部位包括右侧外囊（部分的右IFOF），整个胼胝体和右前侧额叶的部分深部白质。脑区域分析结果表明，代谢综合征受试者右侧IFOF的平均FA值为0.44±0.05，对照组为0.41±0.03。BMI值和FA值之间存在显著的负相关关系（r = -0.56，P <0.04）。

White Matter Alteration in Metabolic Syndrome

OBJECTIVE 

We explored the regional pattern of white matter alteration in subjects with metabolic syndrome. We also investigated whether white matter alteration was correlated with BMI.

RESEARCH DESIGN AND METHODS 

Seven middle-aged men with metabolic syndrome and seven without metabolic syndrome underwent diffusion tensor imaging with a 3T magnetic resonance imaging imager. We analyzed the fractional anisotropy (FA) values by using a tract-based spatial statistics technique (whole-brain analysis). We subsequently focused on measuring the mean FA values of the right inferior fronto-occipital fasciculus (IFOF) of all subjects by tract-specific analysis (regional brain analysis). We used Pearson correlation coefficient to evaluate the relationship between BMI and mean FA values of the right IFOF.

RESULTS 

In the whole-brain analysis, subjects with metabolic syndrome had significantly lower FA values than control subjects in part of the right external capsule (part of the right IFOF), the entire corpus callosum, and part of the deep white matter of the right frontal lobe. In the regional brain analysis, the mean FA value of the right IFOF was 0.41 ± 0.03 for subjects with metabolic syndrome and 0.44 ± 0.05 for control subjects. A significant negative correlation was observed between BMI and FA values in the right IFOF (r = 0.56, P < 0.04).

CONCLUSIONS 

Our results show that microstructural white matter changes occur in patients with metabolic syndrome. FA values may be useful indices of white matter alterations in patients with metabolic syndrome.