Resting-State Functional Connectivity of the Precuneus Associated with Suicidality in Adolescents with Major Depressive Disorder

Abstract

Background: Major depressive disorder (MDD) often begins in adolescence and is associated with increased risk for suicidal thoughts and behaviors, or suicidality. fMRI research investigating suicidality in adolescent populations is limited. Based on the interpersonal theory of suicide, which posits that suicide is the result of perceived burdensomeness and thwarted belongingness, the precuneus is an area of interest in this population due to its role in self-referential processing. Further, examining a potential moderation effect of non-suicidal self-injury (NSSI) may also be of interest, as NSSI may lay the groundwork for the third component of this theory, an acquired capability for suicide. Method: Fifty-eight adolescents with a primary diagnosis of MDD completed a self-report measure, which included a suicidality index, and a resting-state fMRI scan. Whole-brain connectivity analyses were conducted using the left and right precuneus as a seed and was correlated with scores on the suicidality index. We also examined whether the presence of greater than 4 lifetime episodes of NSSI moderated any findings. Results: While controlling for depression severity, suicidality was positively associated with RSFC between the left precuneus and left pre- and post-central gyri and middle and superior frontal gyri. There was no significant effect of NSSI history on this relationship. Conclusion: Increasing levels of suicidality may be associated with hyperconnectivity between the precuneus, an area important in self-referential processing, and areas implicated in empathy, social processing, and reorienting attention. These findings provide a neurobiological complement to the interpersonal theory of suicide and represent possible neurobiological targets for intervention and prevention of suicidal thoughts and behavior.