Oct. 6 (Bloomberg) -- Bipolar illness in children leads to severe mood swings in 44 percent of adults and drug and alcohol abuse in about a third, according to an 8-year study.

Diagnosis of bipolar disorder in children is controversial, because doctors had previously thought that children couldn't get severely depressed or severely elated, said Barbara Geller, the study's lead author and a professor of psychiatry at Washington University in St. Louis.

If bipolar children become bipolar adults, doctors should treat more aggressively to prevent the disease from getting worse, Geller said. The reported rate of substance abuse in the study population is similar to numbers previously found in bipolar adults, the authors said.

``It's hard to imagine that children can have this severe illness,'' Geller said in a telephone interview on Oct. 10. Symptoms of mania in adults are similar to what's seen in normal children, she said: ``You're asking people to believe children can be too happy, too grandiose, and that's what kids are like normally. At what point are they impaired?''

The researchers followed 108 children diagnosed with bipolar disorder and studied them for eight years. The kids were an average age of 11 when they were diagnosed.

Bipolar disorder, also called manic-depressive illness, causes extreme mood swings. Mania makes patients irritable or excitable, after which patients may feel depressed. People may feel normal between the cycles.

Treatments can include therapy and medications such as lithium, Abbott Laboratories' Depakote, Johnson & Johnson's Risperdal, and Eli Lilly & Co.'s Zyprexa.

Periods of No Symptoms

About 87 percent of the children had periods of no symptoms after being treated, though about three-quarters relapsed, Geller's team found. The bipolar kids spent about two-thirds of the study period with mood disturbances.

About a third of the patients' time was in a manic episode. Manic children may commandeer a classroom, correct their own papers, or think they're entitled to tell their principals which teachers ought to be fired, Geller said.

Patients who had mothers who were more understanding and compassionate toward them were less likely to relapse after recovery, Geller's team found. It wasn't clear why, Geller said. She pointed to data in depressed children that showed if their mothers were treated for depression, the children improved.

``Regardless of medication, you must pay attention to the mother-child relationship,'' Geller said. ``That's the practical clinical implication.''

About half of the 108 children were 18 when the study ended. Geller said the percentage of the children who would relapse may be conservative, since half the study population isn't adult yet.

To contact the reporter on this story: Elizabeth Lopatto in New York at elopatto@bloomberg.net.

Last Updated: October 6, 2008 16:00 EDT