Description

• An episodic mood disorder of at least one manic or mixed (mania and depression) episode that causes marked impairment, psychosis, and/or hospitalization
• Symptoms are not caused by a substance or general medical condition.

Geriatric Considerations
In new onset in older patients (>50 years of age), a workup for organic or chemically induced pathology is recommended.

Pediatric Considerations
Need for clarity of symptoms is critical to differentiate between attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), disruptive mood dysregulation, and other diagnoses with overlapping symptoms that are common in childhood.

Pregnancy Considerations

• Pregnancy does not reduce the risk of mood episodes.
• Need to weigh risk of fetal and maternal exposure to mood episode to that of medication
• Avoid divalproex (Depakote) due to high teratogenicity risk.
• Postpartum carries high risk of severe acute episode with psychosis and/or infanticidal ideation.

Epidemiology

Onset usually between 15 and 30 years of age, average of 25 years

Prevalence

• 1–1.6% lifetime prevalence
• Manic episodes more common in men; depressive episodes more common in women

Etiology and Pathophysiology

• Dysregulation of biogenic amines or neurotransmitters (particularly serotonin, norepinephrine, and dopamine)
• MRI findings suggest abnormalities in prefrontal cortical areas, striatum, and amygdala that predate illness onset (1)[C].

Genetics

• Monozygotic twin concordance 40–70%; dizygotic 5–25%
• 50% have at least one parent with a mood disorder.

General Prevention

Treatment adherence and education help to prevent relapses.

Commonly Associated Conditions

Substance abuse (60%), ADHD, anxiety disorders (~50%), and eating disorders