Heightened subjectieve experience of depression in borderline personality disorder

Despite the frequent comorbidity of major depression and borderline personality disorder (BPD), limited research has examined what effect this comorbidity has on the severity, course, and presentation of depression. The purpose of this study was to examine whether the severity of major depressive disorder (MDD) in the context of comorbid borderline personality disorder (BPD) differs from MDD when comorbid BPD is not present and to determine whether different measures of depression yield convergent findings. Sixty patients diagnosed with DSM-IV MDD participated in this study. Twenty-nine were diagnosed with DSM-IV BPD, while the remaining 31 had no Axis 11 diagnosis. Depression was evaluated with both clinician (Hamilton Rating Scale for Depression) and self-report (Beck Depression Inventory) ratings. While the two groups were rated as similarly depressed by clinicians on the overall rating and the factor scores, the MDD/BPD group reported more severe depressive symptoms on the self-report measure. This difference was significant even after controlling for clinician-rated severity. Gender interacted with diagnosis, males in the BPD group showed the largest discrepancies between clinician ratings and self-reports. Post-hoc analyses of HDRS factors with the BDI showed that the clinician-rated cognitive disturbance and retardation factors were correlated with self-rated severity overall. Within subgroups, only the retardation factor was correlated with the BDI. Our results suggest that while depressed individuals with and without BPD may be rated as similarly depressed when assessed with objective rating methods, the subjective experience of the depression may be rated as more intense or severe by patients with comorbid BPD. The mechanism underlying this effect remains unknown, and requires further research.