Presence of irritability during depressive episodes in bipolar disorder.
BACKGROUND
This study examined the prevalence of irritability in patients with bipolar I disorder during an episode of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) major depression who do not meet criteria for a mixed episode.


METHODS
A chart review of 111 patients with bipolar I disorder treated at the Massachusetts General Hospital Bipolar Clinic between 1998 and 2000 identified 34 patients who met criteria for a DSM-IV major depressive episode in the absence of (1) mood elevation and/or (2) irritability associated with any additional above threshold DSM-IV symptoms of mania. Data gathered from the charts utilized prospective ratings made routinely at each clinic visit using the Clinical Monitoring Form (CMF), a structured assessment instrument which includes modified versions of the mood modules of the Structured Clinical Interview for DSM-IV. Data from these 34 patients were reviewed to determine the presence of irritability.


RESULTS
The frequency of abnormal irritability in these 34 patients followed a bimodal distribution: 26% of the patients showed abnormal irritability > or =75% of the time, compared with 68% of the patients with abnormal irritability < or =30% of the time. Of the high-irritability patients, psychomotor agitation was rated as definitely present to a significant degree in 44%. Talkativeness and distractibility were rated present but subthreshold in one patient each. All other symptoms of DSM-IV mania were absent.


CONCLUSIONS
Approximately 25% of patients with bipolar I disorder who meet criteria for a DSM-IV major depressive episode also experienced substantial irritability in the absence of associated symptoms of mania. Our results suggest that abnormal irritability is not limited to mania or mixed states.
Department of Psychiatry, Psychiatric Neuroscience Program and Bipolar Research Program, Harvard Medical School 149-2611, Massachusetts General Hospital Bldg. 149, 13th Street, Charlestown, MA 02129, USA. tdeckersbach@partners.org
Thilo
T
Deckersbach
Roy H
RH
Perlis
W Gordon
WG
Frankle
Stephen M
SM
Gray
Louisa
L
Grandin
Darin D
DD
Dougherty
Andrew A
AA
Nierenberg
Gary S
GS
Sachs
D000328:Adult; D001714:Bipolar Disorder / Q000523:psychology*; D005260:Female; D006801:Humans; D007508:Irritable Mood; D008297:Male