Relationship between affective state and personality ratings in inpatient depression

Abstract

BACKGROUND: The relationship between major depressive disorder (MDD) and personality disorders is complex and has implications for diagnosis and treatment. We explored the relationship between these disorders quantitatively and qualitatively. METHODS: We conducted a structured observational study exploring depressive symptoms and neurocognitive functions over the span of an inpatient admission in those with MDD and personality disorders. Sixty inpatients presenting with depressive symptoms completed ratings of mood and selected neurocognitive functions. Diagnosis was confirmed in structured clinical interviews at discharge and used to allocate patients to one of two main groups for analysis: those with MDD and those with a personality disorder (with or without MDD). Qualitative methods were used to assess behaviours of patients on the ward and the opinions of staff regarding diagnosis. RESULTS: On admission, observer-based ratings of depression were significantly higher in the MDD group, while subjective ratings of depression were higher in the personality disorder group. Depression rating scores decreased in both groups over the course of admission, but at discharge, the personality disorder group continued to report higher subjective ratings. The personality disorder group also rated themselves as more cognitively impaired than the MDD group, and unlike the MDD group, they did not report subjective improvements in cognitive function over the course of admission. An objective assessment of cognitive functions found improvements in both groups. The personality disorder group also reported a greater degree of childhood trauma compared with the MDD group. Of the patients in the MDD group, 54% were given personality disorder–related diagnoses by staff. Some of the behaviours that were only exhibited by personality disorder group inpatients were ‘overinvolved in the care of other patients’, ‘inappropriate amusement of other patients’ distress’, ‘patient seeking involvement of family’ and ‘self-harming repeatedly on the same site’, while ‘psychomotor retardation’ was only observed in the MDD group. CONCLUSIONS: The presence of a personality disorder was associated with greater subjective severity of depressive symptomatology and neurocognitive functioning, despite similar or lower objective severity in comparison with those with MDD. Qualitative differences in the behaviour of those in the different groups were observed, as well as discrepancies in the diagnostic labels applied by team members.