Depressive symptoms and neuroanatomical structures in community-dwelling women: A combined voxel-based morphometry and diffusion tensor imaging study with tract-based spatial statistics

Abstract

Depressive symptoms, even at a subclinical level, have been associated with structural brain abnormalities. However, previous studies have used regions of interest or small sample sizes, limiting the ability to generalize the results. In this study, we examined neuroanatomical structures of both gray matter and white matter associated with depressive symptoms across the whole brain in a large sample. A total of 810 community-dwelling adult participants underwent measurement of depressive symptoms with the Center for Epidemiologic Studies Depression Scale (CES-D). The participants were not demented and had no neurological or psychiatric history. To examine the gray and white matter volume, we used structural MRI scans and voxel-based morphometry (VBM); to examine the white matter integrity, we used diffusion tensor imaging with tract-based spatial statistics (TBSS). In female participants, VBM revealed a negative correlation between bilateral anterior cingulate gray matter volume and the CES-D score. TBSS showed a CES-D-related decrease in fractional anisotropy and increase in radial and mean diffusivity in several white matter regions, including the right anterior cingulum. In male participants, there was no significant correlation between gray or white matter volume or white matter integrity and the CES-D score. Our results indicate that the reduction in gray matter volume and differences in white matter integrity in specific brain regions, including the anterior cingulate, are associated with depressive symptoms in women.

Keywords: Anterior cingulate gyrus; CES-D, Center for Epidemiologic Studies Depression Scale; DTI, diffusion tensor imaging; Diffusion tensor imaging; FA, fractional anisotropy; MD, mean diffusivity; RD, radial diffusivity; Subclinical depression; TBSS, tract-based spatial statistics; Tract-based spatial statistics; VBM, voxel-based morphometry; Voxel-based morphometry.

Figures

Fig. 1

Results from multiple regression in female participants with a threshold of P< 0.001 (uncorrected data). Gray matter volumes in the right rostral anterior cingulate gyrus (a) and bilateral dorsal anterior cingulate gyri (b) were negatively correlated with depressive symptoms (P< 0.05, FWE-corrected, cluster level). Cluster locations, sizes, and significance values are shown in Table 2. R and L indicate right and left, respectively. Color scale (0–4) represents t values.

Fig. 2

Correlation between FA, RD, MD, and the CES-D score as identified by TBSS in female participants. The statistical image was thresholded at P< 0.05 and overlaid on the mean FA map of all participants. There were significant negative correlations between FA and the CES-D score (blue–light blue), and positive correlations between RD as well as MD and the CES-D score (red–yellow). L indicates left.

Fig. 3

Blue voxels show the regions where FA was reduced in association with the CES-D score in female participants (P< 0.05) overlaid on the mean FA skeleton (green voxels). The background image is the mean FA map of all participants. Arrows indicate the right dorsal anterior cingulate region (Talairach coordinates: x= 6, y= −13, z = 28). The same region was positively correlated with RD (not shown in this figure). A and P indicate anterior and posterior, and R and L indicate right and left, respectively.