| Bipolar Disorder | Description | Annual Prevalence |
|---|
| Bipolar I disorder | Episodes of mania that include an “abnormally, persistently elevated, expansive, or irritable mood and persistently increased activity or energy that is present for most of the day, nearly every day, for a period of at least 1 week”. This may be preceded by hypomania or depression. | 0.6% |
| Bipolar II disorder | Repeated major depressive episodes (lasting at least 2 weeks) and “at least one hypomanic episode,” which must last for a minimum of 4 days. | 0.8% |
| The two forms of bipolar disorder have distinct patterns of highs and lows. Looking at the annual prevalence (yearly occurrence) of these disorders, you can see that they are relatively rare. |
| SOURCE: DSM–5 (AMERICAN PSYCHIATRIC ASSOCIATION, 2013). |