Triple Network Model-Based Functional Dysconnectivity in Young People With Major Affective Disorders With or Without Current Suicidal Ideation.

Background: The association between functional dysconnectivity in the triple networks-the default mode network (DMN), salience network (SN), and frontoparietal network (FPN)-and current suicidal ideation (CSI) in young people with major affective disorders remains unclear. Methods: This study included 158 young people (mean age: ∼18 years) with major affective disorders (101 with CSI and 57 without CSI) and 64 age- and sex-matched healthy control individuals. Both major depressive disorder and bipolar disorder were diagnosed according to the DSM-5 criteria. CSI was defined by a Montgomery-Åsberg Depression Rating Scale suicide item score of ≥2. All participants underwent resting-state functional connectivity magnetic resonance imaging. Seed-based connectivity analyses were performed, with adjustment for diagnosis and prior suicide attempts. Results: Compared with the non-CSI group, the CSI group exhibited hyperconnectivity between the anterior insula (SN) and hippocampus as well as between the posterior parietal cortex (FPN) and rectus gyrus (DMN) and hypoconnectivity between the amygdala (SN) and cerebellum crus II. Both the CSI and non-CSI groups exhibited increased functional connectivity between the posterior parietal cortex and emotional perception-related regions, specifically, the superior and middle temporal gyri, compared with healthy control individuals. Discussion: Suicidality is associated with extensive and pronounced functional dysconnectivity in the SN, FPN, and DMN in young people with major affective disorders.