Mood and sleep symptoms distinguish bipolar from attention disorder in young children

MedWire News: Elevated mood and decreased sleep can distinguish bipolar disorder from attention-deficit hyperactivity disorder in very young children, study results suggest.

“Considerable controversy surrounds the nature of the earliest symptom expression of childhood-onset bipolar illness,” explain Robert Post (Pennsylvania State University Medical School, Hershey, USA) and team.

They add that childhood-onset bipolar disorder and attention-deficit hyperactivity disorder often have similar symptoms in young children and it is therefore difficult to distinguish one disorder from the other at this age.

To gain better insight into the early symptoms of bipolar disorder in young children, the researchers examined the course of individual symptoms over the first 10 years of life in 27 children with bipolar disorder, who were diagnosed before 9 years of age, and 22 children with attention-deficit hyperactivity disorder.

The children were rated by a parent for the presence and severity of 37 symptoms. These were rated on a scale from 0 to 3, with 3 representing the most severe degree of impairment in the child's usual family, social or educational roles.

The team found the symptoms of hyperactivity, impulsivity and decreased attention span were very common and showed a similar course in both groups.

“This might be expected because not only are these classic symptoms of attention-deficit hyperactivity disorder, but are common in bipolar illness itself,” note the researchers.

However, extended periods of mood elevation and decreased sleep were significantly more common in the bipolar children than in those with attention-deficit hyperactivity disorder, and were strong differentiators between the two disorders from as young as 3 years of age. Furthermore, the differences between bipolar children and those with ADHD regarding these symptoms increased in magnitude over the first 10 years of life.

Depressive symptoms were later differentiators that became significant from around 7 years of age.

Irritability and poor frustration tolerance differentiated the two groups only in their greater incidence and severity in bipolar children, compared with a more moderate incidence and course in those with attention-deficit hyperactivity disorder.

Dr Post and team summarise in the journal Bipolar Disorders: “The presence of periods of mood elevation, either brief or extended, in the bipolar child was highly discriminatory, beginning in the earliest years of life.”

Commenting on the implications of the findings, they conclude: “One can be hopeful that earlier recognition, diagnosis, and concerted treatment with one or more mood stabilizers or atypical antipsychotics in the context of appropriate psychosocial therapies, in lieu of treatment as usual, might yield a better outcome and, ultimately, a more benign course of illness.”