Bipolar disorder is a mental illness that causes dramatic shifts in a person’s mood, energy and ability to think clearly. People with bipolar experience high and low moods—known as mania and depression—which differ from the typical ups-and-downs most people experience. (NAMI)

The average age-of-onset is about 25, but it can occur in the teens, or more uncommonly, in childhood. The condition affects men and women equally, with about 2.8% of the U.S. population diagnosed with bipolar disorder and nearly 83% of cases classified as severe. (NAMI)

If left untreated, bipolar disorder usually worsens. However, with a good treatment plan including psychotherapy, medications, a healthy lifestyle, a regular schedule and early identification of symptoms, many people live well with the condition. (NAMI)

Scientists have not yet discovered a single cause of bipolar disorder. Currently, they believe several factors may contribute, including:

• Genetics. The chances of developing bipolar disorder are increased if a child’s parents or siblings have the disorder. But the role of genetics is not absolute: A child from a family with a history of bipolar disorder may never develop the disorder. Studies of identical twins have found that, even if one twin develops the disorder, the other may not.
• Stress. A stressful event such as a death in the family, an illness, a difficult relationship, divorce or financial problems can trigger a manic or depressive episode. Thus, a person’s handling of stress may also play a role in the development of the illness.
• Brain structure and function. Brain scans cannot diagnose bipolar disorder, yet researchers have identified subtle differences in the average size or activation of some brain structures in people with bipolar disorder.
• Bipolar I Disorder is an illness in which people have experienced one or more episodes of mania. Most people diagnosed with bipolar I will have episodes of both mania and depression, though an episode of depression is not necessary for a diagnosis. To be diagnosed with bipolar I, a person’s manic episodes must last at least seven days or be so severe that hospitalization is required.
• Bipolar II Disorder is a subset of bipolar disorder in which people experience depressive episodes shifting back and forth with hypomanic episodes, but never a “full” manic episode.
• Cyclothymic Disorder or Cyclothymia is a chronically unstable mood state in which people experience hypomania and mild depression for at least two years. People with cyclothymia may have brief periods of normal mood, but these periods last less than eight weeks.
• Bipolar Disorder, “other specified” and “unspecified” is when a person does not meet the criteria for bipolar I, II or cyclothymia but has still experienced periods of clinically significant abnormal mood elevation.