NEW YORK — Significant differences are apparent in the rates of mania and types of externalizing comorbidity between children, adolescents, and adults with bipolar disorder, Dr. Gabrielle A. Carlson reported at a psychopharmacology update sponsored by the American Academy of Child and Adolescent Psychiatry.
The onset of bipolar disorder (BD) also seems to vary depending on gender, said Dr. Carlson, professor of psychiatry and pediatrics and director of child and adolescent psychiatry at the State University of New York at Stony Brook.
Among adults, the mood changes characteristic of mania include grandiosity, marked euphoria, and irritability, with associated racing thoughts, mood lability, and increased psychomotor activity.
But symptoms differ among younger patients with the disorder.
“It's irritability and aggression that's grabbing us by the lapels with bipolar disorder in children and adolescents,” Dr. Carlson said. “It's not that they're coming in euphoric … saying they're on cloud nine or president of the United States.”
A growing body of evidence also suggests that differences exist in bipolar disorder based on age at onset, Dr. Carlson said.
A recent study by Dr. Gabriele Masi and colleagues involved 136 consecutive patients, including 80 with bipolar disorder onset before 12 years of age and 56 with adolescent-onset BD (J. Child Adolesc. Psychopharmacol. 2006;16:679–85).
Compared with the adolescent-onset bipolar disorder, patients with childhood-onset were significantly more likely to be male (67.5% vs. 48%) and to have a comorbidity with ADHD (39% vs. 9%) and oppositional defiant disorder (ODD) (36% vs. 11%).
An episodic rather than a chronic course also was significantly more likely to occur in adolescents with the disorder than among children with it (77% vs. 42.5%).
Similar trends were identified in a study now in press by Dr. Carlson and her colleagues that compared 89 patients with BD onset at ages 15–29 years and 34 patients with bipolar disorder onset after age 30.
The patients with earlier-onset bipolar disorder were twice as likely to be male than were the adult-onset patients (55% vs. 26.5%). They also had significantly higher rates of ADHD or oppositional defiant disorder or conduct disorder (26% vs. 9%).
Prospective data are limited, but juvenile-onset bipolar disorder appears to be more chronic and treatment refractory than does adult-onset bipolar disorder.
“Episodes remit more quickly the older you are,” Dr. Carlson said.
Those with very early onset are unlikely to have only one episode. They also take longer to recover from an episode, and are less likely to remit completely between episodes.
However, it remains unclear whether this particular pattern is a reflection of incomplete episode remission or, on the other hand, complications of a comorbid condition, Dr. Carlson explained.
Unpublished secondary analyses of an earlier study by Dr. Carlson and colleagues (Am. J. Psychiatry 2002;159:307–9) identifies significant differences by age of onset in functional outcome after a bipolar episode.
Among 89 patients with bipolar disorder onset at age 15–29 years, 15% of them had a Global Assessment of Functioning score of less than 50 after an episode, compared with 12% of those with bipolar disorder onset after an age of 30 years.
“The combination of externalizing symptoms [ADHD and ODD] and serious mood lability is noxious, impairing, and often enduring,” Dr. Carlson said.
“Intervention is clearly justified; prevention is clearly justified. But we cannot conclude that classic manic depression is the outcome and lifetime medication is justified,” she added.