Dear Dr. Roach: Is it possible for a person to reach the age of 70 and just now be diagnosed with bipolar disorder? Are there degrees of impairment, like with autism -- some worse than others?
A: The hallmark of bipolar disease is mania. "Mania" has a specific meaning in psychiatry: It's a very elevated mood, associated with high amounts of energy and an inability to think clearly, especially to see the consequences of one's actions. Some common features of people in a manic episode include an inflated sense of self-worth, distractibility and racing ideas. People can be very talkative and feel little need to sleep. Dangerously, people in a manic phase can spend large amounts of money and have many sexual indiscretions.
All diseases have a spectrum of severity, and some are quite wide. With bipolar disease in particular, however, there are four distinct forms of the disease. Bipolar I is the classic form, once called "manic depressive illness," where people have episodes of mania, alternating with periods of normal behavior or depression. People with Bipolar II have depressive episodes and some "hypomanic" episodes: periods of high energy (and sometimes profound productivity), usually without the negative aspects of the "full" manic episode. Cyclothymia is a rapid cycling between hypomania and mild depression. There is a fourth type, "unspecified," where people have abnormal mood elevations but don't meet criteria for the other types.
I have rarely seen bipolar disease diagnosed in someone as old as 70. It isn't always clear whether the disease is just manifesting that late, or whether it has been around for many years, but compensated for by the person. Some people don't interact with a lot of family or friends, and manic or hypomanic episodes might be missed. It's possible the 70-year-old in question has a quite mild form.