Exploring clinical characteristics of bipolar depression: internal structure of the bipolar depression rating scale.
OBJECTIVE
Due to its pleomorphic phenomenology, the clinical features of bipolar depression are difficult to assess. The objective of the present study was therefore to explore the internal structure of the Bipolar Depression Rating Scale (BDRS) in terms of the phenomenological characteristics of bipolar depression.


METHODS
Sixty patients with DSM-IV bipolar depression completed the BDRS, depression and excitement subscales of the Positive and Negative Syndrome Scale (PANSS-D and PANSS-E), 17-item Hamilton Depression Rating Scale, Montgomery-Asberg Depression Rating Scale, Young Mania Rating Scale (YMRS), and the Drug-Induced Extrapyramidal Symptoms Scale. The internal structure of the BDRS was explored through hierarchical cluster analysis (HCA) using Ward's method and multidimensional scaling (MDS).


RESULTS
From 20-item BDRS data, the HCA yielded two symptom clusters. The first cluster included 12 items of conventional depressive symptoms. The second cluster included eight items of mixed symptoms. The MDS identified a depressive-mixed dimension. The depressive symptom cluster showed a more cohesive and conglomerate cluster structure on the MDS map compared to the mixed symptom cluster. After controlling for the effects of treatment-emergent extrapyramidal symptoms, strong positive correlations were observed between the BDRS and other depression rating scales, and the BDRS also weakly correlated with the YMRS and the PANSS-E.


CONCLUSIONS
The internal structure of BDRS appears to be sensitive to complex features of bipolar depression. Hence, the BDRS may have an advantage in evaluating clinical changes in patients with bipolar depression within the therapeutic process.
Chang
Jae Seung
JS
Department of Neuropsychiatry, Seoul National University Bundang Hospital, Bundang, Seongnam, Gyeonggi, Korea.
Ahn
Yong Min
YM
Yu
Han Young
HY
Park
Hye Jean
HJ
Lee
Kyu Young
KY
Kim
Se Hyun
SH
Kim
Yong Sik
YS
D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects; D001480:Basal Ganglia Diseases / Q000139:chemically induced; D001714:Bipolar Disorder / Q000175:diagnosis*; D016000:Cluster Analysis; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales
D014150:Antipsychotic Agents