Risk Factors

Risk Factors

Between 1 - 2 million Americans are thought to suffer from bipolar disorder. Estimates of the lifetime risk for the disorder run are about 1.25%. There is some indication that the incidence of bipolar disorder may be increasing, but more research is needed to confirm this.

Gender

Bipolar disorder affects both sexes equally, but there is a higher incidence of rapid cycling, mixed states, and cyclothymia in women. Early-onset bipolar disorder tends to occur more frequently in men and it is associated with a more severe condition. Men with bipolar disorder also tend to have higher rates of substance abuse (drugs, alcohol) than women.

Age

Bipolar disorder is the most common psychotic disorder, and experts believe that it occurs in 1% of people among all age groups.

Early-Onset Bipolar Disorder. In one survey, 59% of bipolar disorder patients had their first symptoms when they were children or adolescents. Typically, there was a very long delay until the condition was diagnosed and treated. Bipolar symptoms in young people closely mimic those in adulthood, but may have slight differences:

• The initial episodes are more likely to be depressive. A study reported that 33% of children who experienced major depression developed bipolar I by age 21 and 15% of them had bipolar II disorder.
• Manic phases usually begin in adolescence or young adulthood, with an average age of onset being 18 years. Mood often involves irritability, but in general symptoms, resemble those seen in adults (euphoria and grandiosity, flight of ideas, racing thoughts, and a decreased need for sleep).

Early-onset bipolar disease is also associated with the following characteristics:

• A family history of bipolar disorder is usually present. Children with bipolar disorder who have one or more parents with the same disorder often have a more severe form than does the affected parent.
• A higher rate of co-existing conditions such as panic disorder, conduct disorder, substance abuse, suicidal behavior, and psychotic symptoms may occur during bipolar episodes. Young patients are at higher risk for these complications regardless of the presence or absence of supportive parents.
• The condition is often more severe in children than in adult patients, with a higher risk for mixed mania (simultaneous depression and mania), multiple and frequent cycles, and a long duration of illness without well periods.