Increased suicide attempts in young depressed patients with abnormal temporal-parietal-limbic gray matter volume

Suicide is a major cause of death throughout the world. Approximately 60% of all suicides have a history of depression. Previous studies of structural brain imaging have shown that suicide is often associated with abnormal fronto-limbic networks. However, the mechanism underlying suicide in depression remains poorly understood.

Twenty sex- and age-matched suicidal unipolar patients were compared with 18 non-suicidal unipolar patients and 28 healthy controls. High-resolution T1-weighted 3T magnetic resonance imaging (MRI) scans were acquired. Hamilton Depressive Rating Scale (HAMD) and Self-Rating Depression scale (SDS) were evaluated. The criterion for suicidality was one or more documented lifetime suicide attempts. A whole-brain optimized voxel-based morphometry (VBM) approach was applied. The Dysfunctional Attitude Scale (DAS) was used to measure cognitive scheme in depressive patients.

Compared with controls, patients without suicide history showed significant decreased gray matter volume in the left insula lobe [-35 18 9], whereas patients with suicide history showed significantly decreased gray matter volume in the right middle temporal gyrus [60 -53 -8] and increased gray matter volume in the right parietal lobe [39 -39 60]. Compared with the non-suicidal depressed patient group, the suicidal group showed significant decreased gray matter volume in left limbic cingulated gyrus [-2 -21 28]. Moreover, the gray matter volume values in this significantly different brain region were negatively correlated with dysfunctional attitude scores in suicidal depressed patients.

This study needs replication and further clarification in a larger patient population.

Suicide attempts in young depressed patients may be related to abnormal gray matter volumes in temporal-parietal-limbic networks. Specifically, small left limbic cingulate gyrus volumes may be a candidate for the prediction of suicide in young depressed patients.