via
WebMD:
"The most serious risk of rapid cycling bipolar disorder is
suicide. People with bipolar disorder are 10 times to 20 times more likely to commit suicide than people without bipolar disorder. Tragically, 8% to 20% of people with bipolar disorder eventually lose their lives to suicide.
People with rapid cycling bipolar disorder are probably at even higher risk for suicide than those with nonrapid cycling bipolar disorder. They are hospitalized more often, and their symptoms are usually more difficult to control long term.
Treatment reduces the likelihood of serious depression and suicide. Lithium in particular, taken long term, reduces the risk.
People with bipolar disorder are also at higher risk for substance abuse. Nearly 60% of people with bipolar disorder abuse drugs or alcohol. Substance abuse is associated with more severe or poorly controlled bipolar disorder."