Children and teen-agers with bipolar disorder suffer from the illness differently than adults do. Their symptoms last longer and swing more swiftly from hyperactivity and recklessness to lethargy and depression.
This is the first major finding published from the Course and Outcome of Bipolar Illness in Youth, or COBY, research program. Under COBY, psychiatrists from Brown Medical School, the University of Pittsburgh, and the University of California-Los Angeles have studied more than 400 pediatric patients, some for as long as five years, to determine the course of bipolar disorder as well as gauge its behavioral and social effects. COBY is the largest and most comprehensive pediatric study of bipolar disorder to date.
In their first COBY publication, in the Archives of General Psychiatry, researchers report on 263 subjects aged 7 to 17 with bipolar spectrum disorder. Subjects were studied over a roughly two-year period and asked about mood, behavior, and medical treatment. The aim: Determine how bipolar disorder, in all its forms, progresses in children and teens.
Martin Keller, M.D., a pioneer in designing and conducting long-term studies of major psychiatric disorders, is principal investigator for the Brown Medical School research team.
"Bipolar disorder severely impairs functioning and has a high rate of related psychiatric and physical health issues, such as anxiety and substance abuse," said Keller, the Mary E. Zucker Professor and chair of the Department of Psychiatry and Human Behavior and psychiatrist-in-chief of Brown's seven affiliated hospitals. "These data are essential to improving diagnosis and treatment for a vulnerable population. The data can also inform the design of clinical drug trials so the trials have a maximum likelihood of identifying effective treatments."
Also known as manic-depressive illness, bipolar disorder is marked by dramatic changes in mood, energy level and behavior. One extreme is mania, which can be accompanied by extreme irritability, lack of sleep, poor judgment, restlessness and impulsiveness. The other extreme is depression, which can be characterized by hopelessness, fatigue and, in some cases, suicidal thoughts. These manic and depressive episodes are interspersed with milder symptoms and impaired function in a majority of patients.
Bipolar disorder often begins in late adolescence or early adulthood, although it can develop as early as the preschool years. According to the National Institute of Mental Health, about 2 million American adults suffer from bipolar disorder. At least another 750,000 children and teen-agers live with the illness, the Child & Adolescent Bipolar Foundation estimates.
The COBY study, however, shows that the illness runs a different course in young people than it does in adults. For example, study subjects with bipolar I - the classic form of the illness marked by swings between severe mania and major depression - had symptoms that lasted significantly longer than typically seen in adults.
Mood swings were also more frequent than reported in adults. In fact, researchers noted that many children and teens switched illness sub-types during the study period. For example, one-third of subjects diagnosed with bipolar disorder not otherwise specified - a milder version of the illness - converted to bipolar I or bipolar II during the course of follow-up. This was an important finding. While researchers suspected that such conversions might occur, this is the first large-scale study to clearly document the phenomenon.
"Although moodiness and irritability can be common and normal in teenagers, this study helps to clarify that when these symptoms are excessive, persistent and impairing, a bipolar spectrum illness should be considered," said Henrietta Leonard, M.D., professor of psychiatry and human behavior at Brown and a child psychiatrist with the Bradley Hasbro Children's Research Center.
Jeffrey Hunt, M.D., a clinical associate professor of psychiatry and human behavior and a child psychiatrist at Bradley Hospital, agreed: "For clinicians and parents, this study demonstrates the importance of systematic assessment and follow-up."