Functional connectivity of the default mode network subsystems alterations in suicide attempters with major depressive disorder.

Default mode network (DMN) abnormalities are common in patients with major depressive disorder and suicide attempts (MDD-SA). We aimed to investigate the abnormal functional connectivity (FC) patterns of DMN in MDD-SA. Seventeen DMN components were extracted from 55 MDD-SA, 94 patients with MDD but without suicide attempts (MDD-NoSA), and 71 healthy controls (HC). Compared with HC and MDD-NoSA, patients with MDD-SA revealed reduced FC between the dorsomedial prefrontal cortex (dMPFC) seed and middle frontal gyrus (MFG). Patients with MDD-SA also showed specific increased FC between ventral medial prefrontal cortex (vMPFC) seed and medial superior frontal gyrus. MDD-NoSA showed specific increased FC between dMPFC and cerebellum crus Ⅱ. Both patients with MDD-SA and MDD-NoSA demonstrated increased FC between the vMPFC seed and inferior parietal lobule (IPL) and impaired FC between the anterior medial prefrontal cortex and cerebellum crus Ⅱ than HC. Furthermore, the abnormal FC between the vMPFC seed and IPL was correlated with Montgomery-Asberg Depression Scale in the MDD-NoSA group. Our findings highlighted that these abnormal FC patterns of DMN were associated with pathological mechanisms in patients with MDD-SA and MDD-NoSA.