Study suggests link between manic episodes and full-blown bipolar disorder in high-risk children
New research indicates a significant link between subthreshold manic episodes and the development of bipolar disorder in children of parents with the disorder. The study, published in the American Journal of Psychiatry, suggests clinical assessment and care for these high-risk children could be improved by enabling earlier diagnosis, treatment or preventive measures.
The study is among the first to show subthreshold manic episodes—experiences that approach but do not meet the definition of full-blown bipolar disorder—are important risk factors for the development of bipolar disorder and other mental health conditions in high-risk children. In addition, the study found children of parents with bipolar disorder have much higher rates of hypomania; manic, mixed or hypomanic episodes; and major depressive episodes than other children.
“Mental health practitioners should carefully assess for short episodes of manic symptoms, major depression and disruptive behavior disorders in high-risk children, as these are risk factors for the future onset of bipolar disorder,” said David Axelson, M.D., medical director of Behavioral Health at Nationwide Children’s Hospital and senior author on the study. “This may be particularly important if medication is going to be used for treating mood or behavioral symptoms in the child, because some medications might increase the risk of developing mania or psychotic symptoms in someone who is already at very high risk for developing bipolar disorder. Prescribers might choose different medication options, or use lower doses and monitor for problems more closely.”
The cumulative rate of bipolar spectrum disorders at age 21 was 23 percent in the high-risk group compared to 3.2 percent in the comparison group. The average age of onset for a bipolar spectrum disorder was 12, with the earliest documented manic episode at age 8, highlighting the importance of monitoring mania symptoms for early intervention.
“Most children who have a parent with bipolar disorder will have a diagnosable psychiatric disorder, such as attention-deficit disorder, oppositional defiant disorder, an anxiety disorder or depression, at some point during their youth,” Dr. Axelson said. “However, most children who have a parent with bipolar disorder do not develop bipolar disorder.”
Among the study’s high-risk children who did develop bipolar disorder, nearly all had identifiable mood episodes and other psychiatric disorders before the onset of full-fledged illness. “Short, distinct episodes of manic symptoms were the most specific predictor of developing bipolar disorder in high-risk offspring,” Dr. Axelson said. “But so far, many children with these short manic episodes have not progressed to full-fledged bipolar disorder.”