PEDIATRIC BIPOLAR DISORDER
Pediatric bipolar vs. severe mood dysregulation: New evidence
The controversy over pediatric bipolar disorder has heated up over the past year. A recent study offers evidence for those favoring “narrow” criteria for the pediatric bipolar diagnosis. Researchers interviewed children brought into an NIMH treatment center, and classified 33 as having “narrow phenotype bipolar disorder” (meaning that they met standard DSM-4 criteria, including grandiose manic episodes) vs. 30 as having “severe mood dysregulation” (primary mood irritable, angry or sad, plus hyperarousal symptoms, plus frequent temper tantrums). Next, different researchers interviewed parents of these children to see whether children with narrowly defined bipolar were more likely to have bipolar parents than children with severe mood dysregualtion. These interviewers were blind to the child’s diagnosis. The results? 33.3 % of parents of narrow bipolar kids were diagnosed with bipolar disorder, vs. only 2.7% of parents of mood dysregulation kids.
TCPR’s Take: Since kids with narrow bipolar are about 10 times more likely to have a bipolar parent than kids with severe mood dysregulation, the implication is that severe mood dysregulation is less likely to be “true” bipolar disorder. However, it’s not clear how much this matters, since mood stabilizing medications are often helpful in children with mood dysregulation, perhaps via a non-specific tranquilizing effect. Nonetheless, the study implies that we should be less eager to make the bipolar disorder diagnosis in kids unless they meet standard criteria (Brotman MA, Am J Psychiatry 164:1238- 1241, August 2007).
Provigil better than placebo for bipolar depression
In a study only partially funded by the manufacturer of Provigil (modafinil), 85 patients with bipolar depression, already taking mood stabilizers, were randomly assigned to augmentation with Provigil (N=41) or placebo (N=44). The average Provigil dose was 177 mg/day. Beginning at the two week point, Provigil improved depression symptoms more than placebo, and this advantage continued through the 6 week duration of the study. The Provigil patients had a 44% response rate vs. the placebo patients, who had a 23% response rate. There were no differences between the two groups in rates of manic switching.
TCPR’s Take: At the relatively modest dosing used in this study, the side effects were minimal, and there was little risk for manic switching. The effect appeared to be a true antidepressant effect and not simply a wakefulness effect, as measures of fatigue were not different in the two treatment conditions (Frye MA et al., Am J Psychiatry 2007; 164:1242-1249).
First controlled trial of sibutramine vs. topiramate in bipolar disorder
It was a sorely needed study: compare sibutramine (Meridia) with topiramate (Topamax) in patients with psychotropic-associated weight gain. Sibutramine is generally considered one of the most effective weight loss agents. However, it inhibits the reuptake of both serotonin and norepinephrine, leading to reluctance to use it for patients with bipolar disorder, who could theoretically experience manic switches. In this study, 46 patients with bipolar disorder and obesity were randomly assigned to sibutramine (mean dose, 12 mg/day) or topiramate (mean, 209 mg/day). Weight loss was similar for both, with an average of 4% body weight loss in the sibutramine group vs. 3% in the topiramate group. Many patients dropped out before 24 weeks, but interestingly more patients dropped out due to mood worsening in the topiramate group than the sibutramine group, implying that the fears of manic switching may be over-blown.
TCPR’s Take: Since there was no placebo control, we don’t know for certain that patients’ weight loss was due to a specific effect of either of these meds. But the data imply that sibutramine is safe and effective for weight loss in bipolar disorder. (McElroy SL et al., Bipolar Disorders 2007;9:426-434).