Agitated depression: unipolar? Bipolar? Or both?

Area of Science:

• Psychiatry and Mental Health
• Mood Disorders Research
• Clinical Psychology

Background:

• The classification of agitated depression within mood disorders remains ambiguous.
• Understanding agitated depression is vital due to potential antidepressant-induced agitation.
• Current diagnostic criteria (DSM-IV) offer no definitive classification for agitated depression.

Purpose of the Study:

• To investigate whether agitated depression aligns more with bipolar or unipolar disorders.
• To examine associations between agitated depression and variables characteristic of bipolar disorders.
• To assess the relationship between agitated depression and bipolar II disorder.

Main Methods:

• A comparative study involving 151 unipolar and 226 bipolar II major depressive episode (MDE) outpatients.
• Patients were interviewed using the Structured Clinical Interview for DSM-IV.
• Statistical analyses included t-tests, proportion tests, and logistic regression to compare agitated and non-agitated MDE groups.

Main Results:

• Agitated MDE was observed in 22.5% of patients.
• Agitated MDE patients exhibited significantly more bipolar II disorder, higher prevalence of females, earlier onset, longer illness duration, more recurrences, atypical features, and family history of bipolar disorders.
• Logistic regression controlling for bipolar II disorder rendered initial significant differences non-significant.

Conclusions:

• Agitated major depressive episode may be closer to the bipolar spectrum than unipolar disorder.
• The association with bipolar II disorder and bipolar-typical variables supports this potential classification.
• Further research is necessary to confirm the placement of agitated depression within mood disorder typologies.