Key points
- All bipolar disorders are characterized by both manic or hypomanic episodes and depressive episodes.
- Symptoms are severe and differ from the normal ups and downs that people experience in their lives.
- Most people with bipolar disorder can be treated in the community, but many delay seeking treatment.
Types of bipolar disorders
The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) lists the following types of bipolar disorders:
- bipolar 1 disorder
- bipolar 2 disorder
- cyclothymic disorder
- substance/medication-induced bipolar and related disorder
- bipolar and related disorder due to another medical condition
- other specified bipolar and related disorder
- unspecified bipolar and related disorder
- specifiers for bipolar and related disorders.
Prevalence
- About 1% of adults experience bipolar disorder.
- 25–50% of people with depression in primary care settings have a bipolar disorder.
- Men and women have similar rates of bipolar disorder.
- Women are hospitalized for bipolar disorders more often than men, especially between ages 40–44.
- Manic episodes are more common in men and depressive episodes are more common in women.
- Bipolar 1 disorder can start earlier than depression. Onset is anywhere from childhood to age 50–60, with a mean age of 30.
- A higher than average rate of bipolar 1 disorder is found among upper socio-economic groups.
Symptoms
All bipolar disorders feature both manic or hypomanic episodes and depressive episodes.
Manic episodes
- are a period of at least one week in which a person is abnormally energetic, talks more, sleeps less, has racing thoughts, poor judgment or psychotic symptoms
- are severe enough to cause disruption to daily life or hospitalization.
Hypomanic episodes
- are less severe than manic episodes and may not cause disruption to daily life, but may progress to a full-blown manic episode.
Depressive episodes
- are characterized by persistent low mood, loss of interest or pleasure in daily activities, weight loss or gain, apathy, feelings of worthlessness, suicidal thoughts
- may affect school and work performance.
Hallucinations or delusions may be associated with episodes of depression or mania.
Causes
Genetic factors
- A family history of bipolar disorder is one of the strongest and most consistent risk factors for bipolar disorders.
Environmental factors
- Bipolar disorder is more common in high-income than low-income countries.
- People who are separated, divorced or widowed have higher rates of bipolar disorder than people who are single or have never married.
- Stress does not cause bipolar disorder but may trigger symptoms in a person who has the disorder.
Biological factors
- Some studies show that the brains of people with bipolar disorder differ from people who do not have bipolar disorder.
- Stress does not cause bipolar disorder but may trigger symptoms in a person who has the disorder.
Prognosis
- The prognosis for a single episode of mania or depression is good; however, there is a significant risk of recurrence. A manic episode is usually followed by an episode of depression. Some people fully recover, but many continue to have chronic mood instability.
Evidence summary
American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Washington, DC: Author.
Health Canada. (2002). A Report on Mental Illnesses in Canada. Ottawa, ON: Author.
McIntyre, R. (2011). The patient who is manic. In D. Goldbloom & J. Davine (Eds.), Psychiatry in Primary Care: A Concise Canadian Pocket Guide (pp. 27–44). Toronto, ON: Centre for Addiction and Mental Health.
National Institute of Mental Health. (n.d.). Bipolar Disorder. Bethesda, MD: Author.