Aberrant structural and functional alterations in patients with insomnia comorbid anxiety: A combined voxel-based morphometry and functional connectivity study

Chronic insomnia disorder (CID) is commonly comorbid with generalized anxiety disorder (GAD), resulting in possible alterations in patient's brain structure and function. However, its imaging manifestation and pathogenesis remains unclear. To investigate the imaging manifestations of patient with CID comorbid GAD, as well as its possible pathogenesis. A total of 57 patients with CID comorbid GAD and 57 healthy controls (HC) were respectively recruited in this study. Voxel-based morphometry (VBM) and functional connectivity (FC) were used to observe the gray matter volume (GMV) and functional alterations. Correlation analysis was used to discover associations between brain alterations and clinical features. The patients presented with decreased GMV in the left cerebellum, right cerebellar peduncle and left insula, increased FC in the left cerebellum-right angular gyrus and the left insula-anterior left cingulate gyrus, and decreased FC in left cerebellum-middle left cingulate gyrus, left cerebellum-left medial superior frontal gyrus, and left insula-left superior postcentral gyrus. There was an association between CID comorbid with GAD and some of these brain alterations. Reduced GMV in left insula and decreased FC in left cerebellum-middle left cingulate gyrus and left cerebellum-left medial superior frontal gyrus may contribute to the comorbidity of CID and GAD.