Identifying functional brain abnormalities in migraine and depression comorbidity.

Background:Migraine and major depressive disorder (MDD) are both highly prevalent brain disorders and are often comorbid. However, the common and distinctive neural mechanisms underlying these disorders and the brain function alterations associated with their comorbidity are largely unknown. We aimed to explore the functional abnormalities of the brain associated with the co-occurrence of migraine and depression. Methods:High-resolution T1-weighted and resting-state functional magnetic resonance images (MRI) were acquired from 93 well-matched patients with comorbid migraine and depression, patients with migraine, patients with MDD, and healthy controls. Voxel-wise analysis of variance (ANOVA) and a two-sample t-test of multiple functional variables were performed among the groups. Furthermore, correlation analysis was conducted to detect the clinical significance of the altered functional regions in the brain. Results:Migraine patients with and without depression revealed widely shared regional networks of functional changes. Brain function changes in the right paracentral lobule and fusiform were specific to patients with comorbid migraine and depression [P<0.05, cluster-level familywise error (FWE)-corrected], while changes in the left thalamus, medial orbital of superior frontal gyrus and triangular part of the inferior frontal gyrus were specific to patients with migraine (P<0.05, cluster-level FWE-corrected). Importantly, the brain activity of the right paracentral lobule, left calcarine, and left dorsolateral superior frontal gyrus was associated with emotional symptoms in the pooled migraine data (P<0.05). Conclusions:These findings help to identify the neural correlates underlying patients with migraine and those with comorbid migraine and depression. These shared and distinct brain changes could be used as potential image markers to decipher the comorbidity of the 2 disorders.