A recent Science Daily post examined the findings of this study which indicate that a small percentage of children with bipolar disorder experience manic episodes without extreme elation, which is one of the hallmarks of the disorder. These children are diagnosed as bipolar based on irritable mood alone.

“Diagnosing children with bipolar disorder is challenging. One of the chief controversies is whether irritability should be included among the criteria for this diagnosis because it can also overlap with a number of other psychiatric disorders, such as attention deficit hyperactivity disorder,” said lead author Jeffrey Hunt, MD, a child psychiatrist and training director at Bradley Hospital, in Science Daily.

“Our findings confirm that while irritable-only mania is uncommon, it does exist – particularly in younger children – and should be considered in a bipolar diagnosis.”

The disorder is characterized by dramatic mood swings from euphoria, elation and irritability to severe depression. Bipolar often begins late in adolescence or early adulthood and studies have shown a drastic increase in the number of children and teens being treated for this disorder in the last ten years.

Within this particular study, 10 percent of children fell into the irritable-only category and 15 percent were elated-only. Almost 75 percent of participants experienced both elation and irritability. While the irritability-only children were significantly younger than the other two groups, this appeared to be the only demographic difference in the groups.

One identified difference in the groups was that depression and alcohol abuse in second-degree relatives occurred more frequently in the irritable-only subgroup than in any other group.