White Matter Alteration in Metabolic Syndrome:Diffusion Tensor Analysis

Keigo Shimoji, MD, Osamu Abe, MD, PHD, Takanori Uka, MD, PHD, Hasina Yasmin, MBBS, PHD, Koji Kamagata, MD, Kouichi Asahi, MD,
Masaaki Hori, MD, PHD, Atsushi Nakanishi, MD, PHD, Yoshifumi Tamura, MD, PHD, Hirotaka Watada, MD, PHD, Ryuzo Kawamori, MD, PHD and Shigeki Aoki, MD, PHD

Published online before print November 19, 2012, doi: 10.2337/dc12-0666 Diabetes Care November 19, 2012

Abstract
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.