Amygdala volume and depressive symptoms in patients with borderline personality disorder

Borderline personality disorder (BPD) is characterized by a high prevalence of comorbid psychiatric disorders, including major depression (MD). The aim of this study was to examine whether a co-occurrence of MD is associated with structural changes in the amygdala of BPD patients.

Twenty-five right-handed, female patients with BPD and 25 matched healthy control subjects were examined. Diagnoses of BPD and MD were made according to DSM IV. Depressive symptomatology was determined with the Hamilton Depression Scale (HAMD). Magnetic resonance imaging scans were performed with 1.5 T Magnetom Vision (Siemens, Erlangen, Germany). The software program "BRAINS" was applied for brain volumetry and segmentation. The amygdala was delineated as "region of interest."

Comparison of amygdala volumes between the whole group of BPD patients and control subjects revealed no significant difference. Amygdala volumes in both hemispheres were significantly larger in BPD patients with MD compared with those without MD. There was a significant correlation in BPD patients between left amygdala volume and depressive symptoms as measured by HAMD.

Correlation of amygdala volume with depression in BPD patients might indicate a causal relationship. Future studies should clarify whether amygdala enlargement is a risk factor for MD in BPD patients or a consequence of the affective disorder.