Background: Non–alcohol-dependent heavy drinkers, as well as alcohol-dependent individuals, show brain atrophy. The purpose of this study was to evaluate whether there are correlations between global and regional gray matter volumes and the lifetime alcohol intake using volumetric analysis and voxel-based morphometry (VBM) among Japanese non-alcohol–dependent male individuals.
Methods: High-resolution three-dimensional magnetic resonance images were acquired from 405 Japanese non-alcohol–dependent male individuals. The collected images were normalized, segmented for volumetric analysis, and additionally smoothed for VBM. For volumetric analysis, the partial correlation coefficient was estimated between the gray matter ratio, which represents the percentage of gray matter volume in the intracranial volume, and the lifetime alcohol intake adjusted for the age of each subject. Multiple regression analysis was performed among regional gray matter volume, lifetime alcohol intake, and age using VBM.
Results: Volumetric analysis revealed that gray matter ratio showed a negative correlation with the lifetime alcohol intake adjusted for age (p=0.059, partial correlation coefficient=−0.091). The VBM revealed that the gray matter volumes of the bilateral middle frontal gyri showed a significant negative correlation with the lifetime alcohol intake adjusted for age and systolic blood pressure (left side, p=0.006, Z=4.77; right side, p=0.023, Z=4.45, and p=0.046, Z=4.27).
Conclusions: Our study suggests that non-alcohol–dependent Japanese male individuals show that both global gray matter volume and regional gray matter volume have negative correlations with the lifetime alcohol intake. Our study may contribute to clarifying the mechanism underlying the brain structural changes because of alcohol influence in healthy non-alcohol–dependent individuals.