Aetna Inc. has developed a disease management program aimed at patients who have been hospitalized for bipolar disorder.

Aetna, Hartford, will be working with AstraZeneca P.L.C., London, a pharmaceutical company, to run the program, which will be voluntary and open only to patients ages 18 and older who have been diagnosed with bipolar disorder.

The disorder, formerly known as manic depression, costs U.S. employers about $14 billion per year in lost productivity, and about 25% of the patients who suffer from the disorder eventually attempt suicide, Aetna says.

AstraZeneca makes Seroquel, a drug used to treat bipolar disorder and other forms of mental illness.

Case managers will try to help patients eligible for the program coordinate care and stick to a physician-prescribed treatment plan, Aetna says.

Aetna will start by offering the program to members of fully insured Aetna health maintenance organization plans.