Impact of depressive mixed state in an emergency psychiatry setting: a marker of bipolar disorder and a possible risk factor for emergency hospitalization.
BACKGROUND
Depressive mixed state (DMX) has been reported to be one of the most useful clinical markers for bipolar II disorder (BP-II) in the outpatient setting. However, the significance of DMX in emergency psychiatry has not been well studied.


METHODS
A chart review study of 139 patients who were hospitalized in an emergency psychiatric ward with an initial diagnosis of major depressive disorder (MDD).


RESULTS
In 42 (30.2%) patients, the diagnosis was changed to bipolar disorder after a median observation period of 189 days from hospitalization, and of these, 34 were diagnosed as having BP-II. DMX was observed in 56 (40.3%) patients at the time of hospitalization. Compared with patients who remained in MDD, significantly more patients who later developed bipolar disorder had experienced DMX (59.5% vs. 32.0%, p = 0.0044). In multivariate analysis, DMX was one of the independent predictors of conversion to bipolar disorder (OR 2.45, p = 0.037), and the independent predictors for DMX were chronic depression and atypical features (OR 2.85, p = 0.010; OR 3.67, p = 0.046, respectively). In addition, DMX was significantly more frequently observed at emergency hospitalization than at non-emergency hospitalization (48.6% vs. 29.1%, p = 0.0065).


CONCLUSIONS
A single reviewer evaluated DMX by chart review.


CONCLUSIONS
DMX is a useful marker of bipolar disorder (mainly BP-II) in the emergency psychiatric setting and is closely related to emergency hospitalization for mood disorders. To confirm these findings, a prospective study that systematically evaluates DMX is needed.
Takeshima
Minoru
M
Department of Neuropsychiatry, Ishikawa Prefectural Takamatsu Hospital, Ya-36, Uchi-Takamatsu, Kahoku City, Japan. min-take@p2.tcnet.ne.jp
Kitamura
Tatsuru
T
Kitamura
Maki
M
Kidani
Tomokazu
T
Tochimoto
Shin-Ichi
S
Muramori
Fumihiko
F
Kosaka
Kazuto
K
Hasegawa
Mitsuru
M
Ueno
Katsuhiko
K
Hamahara
Syouni
S
Kurata
Kouichi
K
D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D002908:Chronic Disease; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D004637:Emergency Services, Psychiatric / Q000706:statistics & numerical data*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D015995:Prevalence; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors
D000928:Antidepressive Agents