White matter alterations are associated with suicide attempt in patients with panic disorder

Panic disorder (PD) is associated with an increased risk of suicide attempt (SA). However, no study has examined the neural correlates of SA in PD. The goal of this study was to evaluate alterations in white matter (WM) and gray matter (GM) in patients with PD with and without a history of SA.

Twelve patients with PD and a history of SA (PD+SA) and 24 patients with PD and no history of SA (PD-SA) underwent magnetic resonance imaging (MRI). All patients completed the Scale for Suicide Ideation (SSI), the Panic Disorder Severity Scale (PDSS), and the Beck Depression Inventory (BDI). The groups were matched for age, sex, and BDI and PDSS scores. Voxel-based morphometry and tract-based spatial statistics were used for the imaging analysis.

Although no GM or WM volume differences were observed, increased fractional anisotropy (FA) values were found in the WM tracts of the PD+SA group compared with the PD-SA group. The regions with increased FA included the internal capsule, splenium of the corpus callosum, superior and posterior corona radiata, thalamic radiations, sagittal stratum, and superior longitudinal fasciculus. The FA values for the internal capsule and thalamic radiations were significantly correlated with the SSI scores in the PD+SA group.

The results should be considered preliminary due to the relatively small sample size.

Our data suggest that the aberrant WM integrity of the internal capsule and thalamic radiations may be the significant neural correlate of SA in patients with PD.