Homicide and bipolar I disorder: a 22-year study

Area of Science:

• Forensic Psychiatry
• Psychopathology
• Bipolar Disorder Research

Background:

• Previous research focused on manic episodes and non-serious offenses in bipolar disorder.
• Emerging evidence suggests a link between depressive episodes and violent, homicidal behavior in bipolar disorder.

Purpose of the Study:

• To investigate the characteristics of homicide in patients with bipolar I disorder, differentiating by mood episode polarity (manic vs. depressive).

Main Methods:

• Retrospective chart review of 219 bipolar I disorder offenders treated between 1987-2008.
• Analysis of mood episode characteristics, supplemented by police and prosecutor records.

Main Results:

• Homicide rates were higher during depressive episodes (13.2%) compared to manic episodes (86.8% for all offenses).
• Victims of homicide were more frequently family members in depressive phases (96.2%) versus manic phases (63.9%).
• Altruistic motivation was higher in depressive phases, while impulsivity was common in manic phases; parricide occurred only during manic episodes.

Conclusions:

• Depressive phases of bipolar I disorder carry a significant risk of offenses, especially homicide targeting family members.
• The potential for severe violence, including family-targeted homicide, during depressive episodes requires clinical attention.