Dysfunction of default mode network is associated with active suicidal ideation in youths and young adults with depression: Findings from the T-RAD study

Deaths due to suicide are one of the leading causes of mortality among youths and young adults. Active suicidal ideation (SI) is considered one of the strongest risk factors for suicide. Here, we evaluated the neurocircuitry of SI in a sample of youths and young adults (aged 10–26 years) with current or past diagnosis of either major depression or bipolar disorder who were enrolled in Texas Resilience Against Depression Study (T-RAD), and had neuroimaging and SI (assessed with the 3-item Suicidal Thoughts factor of Concise Health Risk Tracking self-report scale) data available (n = 72, 53 females). Resting-state functional connectivity (FC) was computed amongst 121 cortical and subcortical regions of interest resulting in 7260 FC pairs. Mean (SD) age and SI levels of participants were 19.6 years (4.01) and 1.48 (2.36) respectively. In univariate analyses, 34 out of the 7260 FC pairs were correlated with SI (p < .005). Stronger connectivity of default mode network (DMN) with striatum was associated with higher SI. Conversely, higher SI was associated with weaker connectivity of limbic network with hippocampus, DMN, dorsal attention network, and executive control network. In multivariate analyses, these 34 FC pairs together had an average correlation of 0.54 after five-fold cross-validation. In conclusion, SI was associated with distinct patterns of resting-state functional connectivity among youths and young adults with regions in DMN and the ventral striatum as key nodes.