Bipolar disorders

What are bipolar disorders?

Bipolar disorders are a group of disorders characterised by episodes of mania or hypomania and depression. In between episodes, mild symptoms of mania and/or depression may, or may not, be present. Bipolar disorders characterised in the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, version 5) include bipolar I disorder, bipolar II disorder, and cyclothymic disorder.

A major depressive episode is a period of at least two weeks in which a person has at least five of the following symptoms (including one of the first two): intense sadness or despair; feelings of helplessness, hopelessness or worthlessness; loss of interest in activities once enjoyed; feelings of guilt, restlessness or agitation; sleeping too little or too much; slowed speech or movements; changes in appetite; loss of energy; difficulty concentrating, remembering or making decisions; and/or thoughts of death or suicide.

A manic episode is a period of at least one week when a person is high spirited or irritable in an extreme way most of the day for most days. A manic episode involves changes in normal behaviour such as showing exaggerated self-esteem or grandiosity, less need for sleep, talking more than usual, talking more loudly and quickly, being easily distracted, doing many activities at once, scheduling more events in a day than can be accomplished, embarking on risky behaviour, uncontrollable racing thoughts, and/or quickly changing ideas or topics. These changes in behaviour are significant and clear to friends and family and are severe enough to cause major dysfunction. A hypomanic episode is similar to a manic episode but the symptoms are less severe and need only last four days in a row. Hypomanic symptoms do not lead to the major problems that mania often causes, and the person is still able to function.

The difference between bipolar I disorder and bipolar II disorder is determined by the existence of mania in bipolar I disorder or hypomania in bipolar II disorder.

What is the evidence for rates of bipolar disorders in people with PTSD?

Moderate quality evidence finds the rate of having a current bipolar disorder in people with PTSD ranges between 4% for bipolar II disorder and 19% for bipolar 1 disorder. For any lifetime diagnosis, the rate ranges between 20% for bipolar II disorder and 35% for bipolar 1 disorder.

August 2021

Image: ©Christos Georghiou –

Last updated at: 10:47 pm, 2nd August 2021
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