age of onset
They may also have extreme pleasure-seeking or risk-taking behaviors. Peopleâs symptoms and the severity of their mania or depression vary widely. Although bipolar disorder can occur at any point in life, the average age of onset is 25. Every year, 2.9% of the U.S. population is diagnosed with bipolar disorder, with nearly 83% of cases being classified as severe. Bipolar disorder affects men and women equally.