It varies, some people do okay while others get worse over time. One of the main things is getting and taking the right medications to maintain stability. If you are stable then you certainly aren't getting worse.
As I understand it does for some and not others, my dad has bipolar and it has gotten better with age, he is still on medication but low doses now. But i have heard many stories where people have gotten worse or have had to up there dosages on medication to stay stable as they age.
Freddie
Unfortunetly it appears that it does. I was diagnosed in 1973 as a manic depressive which was later turned to bipolar II. Since then I have been diagnosed bipolar I. I have heard from other bipolar friends of mine that they feel that their bipolar has been getting worse as they get older. That doesn't mean that yours will. With the right medication you can be stable. I am on three medications that have kept me stable for almost four years. I know that finding the right meds are hard to do, but please don't give up. Keep trying and hopefully you will find the right combination.