Progressive brain structural abnormality in depression assessed with MR imaging by using causal network analysis

Abstract

Background As a neuroprogressive illness, depression is accompanied by brain structural abnormality that extends to many brain regions. However, the progressive structural alteration pattern remains unknown. Methods To elaborate the progressive structural alteration of depression according to illness duration, we recruited 195 never-treated first-episode patients with depression and 130 healthy controls (HCs) undergoing T1-weighted MRI scans. Voxel-based morphometry method was adopted to measure gray matter volume (GMV) for each participant. Patients were first divided into three stages according to the length of illness duration, then we explored stage-specific GMV alterations and the causal effect relationship between them using causal structural covariance network (CaSCN) analysis. Results Overall, patients with depression presented stage-specific GMV alterations compared with HCs. Regions including the hippocampus, the thalamus and the ventral medial prefrontal cortex (vmPFC) presented GMV alteration at onset of illness. Then as the illness advanced, others regions began to present GMV alterations. These results suggested that GMV alteration originated from the hippocampus, the thalamus and vmPFC then expanded to other brain regions. The results of CaSCN analysis revealed that the hippocampus and the vmPFC corporately exerted causal effect on regions such as nucleus accumbens, the precuneus and the cerebellum. In addition, GMV alteration in the hippocampus was also potentially causally related to that in the dorsolateral frontal gyrus. Conclusions Consistent with the neuroprogressive hypothesis, our results reveal progressive morphological alteration originating from the vmPFC and the hippocampus and further elucidate possible details about disease progression of depression.

Two distinct subtypes of obsessive compulsive disorder revealed by heterogeneity through discriminative analysis

“…We followed the recommended pipeline of CAT 12 mainly including reorientation of images, segmentation into gray matter, white matter, and cerebrospinal fluid volume. Segmented images were normalized into Montreal Neurological Institute space and resampled to 1.5 × 1.5 × 1.5 mm followed by nonlinear modulation (Ashburner, 2009 ; Han, Chen, et al, 2021 ; Han, Zheng, et al, 2021 ). Finally, the gray matter maps were smoothed using 6 mm full width at half maximum Gaussian kernel (FWHM).…”

Association of Visual Health With Depressive Symptoms and Brain Imaging Phenotypes Among Middle-Aged and Older Adults

“…The present study considered IDPs generated from the T1-weighted structural MRI and dMRI, which have been used to study depression. 46 , 47 , 48 To our knowledge, this is the first population-scale study to examine associations between depressive symptoms and brain IDPs while evaluating visual function. The association between PHQ-2 score and GMV in the supracalcarine cortex was detectable in the whole cohort.…”

Two distinct subtypes of obsessive compulsive disorder revealed by a framework integrating multimodal neuroimaging information

“…All participants were Han Chinese and right‐handed and must meet the additional exclusion criteria: (1) Taking drugs such as anesthesia, sleeping or analgesia in the past 1 month; (2) substance abuse; (3) a history of brain tumor, trauma, surgery or other organic body disease; (4) suffering from cardiovascular diseases, diabetes or hypertension; (5) contraindications for MRI scanning; and (6) other structural brain abnormalities. The data acquisition, preprocessing steps (Han et al, 2018 ; Han et al, 2020 ), voxel‐based morphometry (Ashburner, 2009 ; Han, Chen, et al, 2021 ; Han, Zheng, et al, 2021 ), ALFF, and quality assurance were included in supplementary information S1 .…”