As the medical and mental health community rise to improve diagnosis and treatment of pediatric bipolar disorder (BD), a new syndrome has been identififed that presents similar behaviors but requires a different pharmacological approach. Researchers believe the discovery may help improve care for both pediatric bipolar disorder (BD) and the syndrome called severe mood dysregulation (SMD).
When the scientists measured the brain’s electrical signals during mildly frustrating situations, children with SMD displayed a very different pattern than children diagnosed with BD. The results indicate that different brain mechanisms may lead to irritability in children with SMD, suggesting that they may have an illness other than BD and may require different treatments.
“These aren’t children with the occasional bad moods you see in most kids. They’re typically very ill, with symptoms that interfere with their lives in major ways. Establishing clear diagnostic criteria is an essential step toward making sure they get the help they need,” said NIMH Director Thomas R. Insel, M.D.
The new study shows that clinicians some day could use biological measurements, such as EEGs, to help make psychiatric diagnoses, in combination with clinical symptoms.
Currently, clinicians diagnose mental illnesses based on symptoms alone. The difficulty of diagnosing BD in children is compounded by the frequent co-occurrence of one or more other mental disorders.
Children have a comparatively low rate of BD, but the rate increases with age, to approximately 1 percent among adolescents. About 3 percent of pre-adolescent and adolescent youth are estimated to have SMD.
Mood-stabilizing and antipsychotic medications are used to treat children with BD, although the data on their effectiveness are limited and several studies are underway. Since SMD was only recently defined, there are no systematic studies on its treatment, and children with SMD are often treated as if they have BD.
Defining pediatric BD is a major issue in child psychiatry, because the disorder tends to be severe in this age group and the rate of diagnosed cases is rising. Until recent years, most studies of BD were conducted in adults.
Some researchers maintain that pediatric BD should be defined more broadly to include children with SMD, an assertion countered by the new finding. Results of the study were published in the February 2007 issue of the American Journal of Psychiatry.
The classic definition of BD (http://www.nimh.nih.gov/publicat/bipolarupdate.cfm) includes extreme, sustained mood swings that range from over-excited, elated moods and irritability — the manic phase of the disorder — to depression. In contrast, children with SMD are extremely irritable and hyperactive, but do not have clear-cut manic episodes.
One component of irritability is the tendency to get acutely frustrated when a goal is not met. Thus, through electroencephalograms (EEGs), the researchers could observe the brain’s electrical signals that occurred during frustration while children with either disorder performed simple tasks.
“If future research indicates that BD and SMD are two separate disorders, this could guide parents and physicians toward the right treatments,” said first author Brendan Rich, Ph.D., of the NIMH Unit on Bipolar Spectrum Disorders.
“A good example is that medication prescribed for symptoms seen in SMD, such as stimulant medication, might be inappropriate for a child with classically defined bipolar disorder,” he said.