Relationship between Predominant Episode and Clinical Features in Bipolar Disorder: A Preliminary Study

Seo, Ho Jun; Woo, Young Sup; Chae, Jeong Ho; Jun, Tae Youn; Kim, Kwang Soo; Bahk, Won Myong

Abstract

OBJECTIVE
This study was performed to find clinical implications of distinctive patterns in bipolar patients with predominance of depressive episodes or manic episodes and to find possibilities to predict predominant episodes in bipolar disorder.
METHODS
The recruitment period was between 2002 and 2004, among inpatients who had received psychiatric treatment for bipolar disorder. The data about the number and the polarity of the past episodes were collected through medical records, and subjects were divided into depressive or manic episode predominant groups. The two groups were compared regarding sociodemographic and clinical variables.
RESULTS
74 patients met the inclusion criteria during the study period. 21 subjects were classified as depressive episode predominant group (depressive episode group), and 53 subjects as manic episode predominant group (manic episode group). There were no differences in sociodemographic data, the number of total episodes and hypomanic episodes, and onset age. However, 90.5% (n=19) subjects of depressive episode group showed depressive episode as first episode, and 88.7% (n=47) of manic episode group experienced manic episode as first episode (Chi2=42.13, df=1, p<0.001). Psychotic symptoms were significantly more prominent in the manic episode group (Chi2=6.85, df=1, p=0.009), and the number of subjects who had suicide attempt experience was higher in the depressive episode group (Chi2=7.39, df=1, p=0.007). In the comparison of highest GAF scores during the past year, significant difference was found between the two group (p=0.046), as the mean scores of depressive episode group was 68.33+/-7.47 and manic episode group was 71.51+/-5.42.
CONCLUSION
The results of this study show that there are differences in clinical features according to predominant episodes in bipolar disorder. The type of onset episode appears to be related to predominant episode in this study, and it would be a valid parameter with therapeutic implication in bipolar patients.