Rates of response,euthymia and remission in two placebo-controlled olanzapine trials for bipolar mania

Objective:  Clinically meaningful recovery from acute mania may not be captured by conventionally reported response categorizations. We defined new and stringent criteria for remission in bipolar mania. Using a cohort of patients with acute mania randomized to treatment with either olanzapine or placebo, we contrasted remission rates to findings using previously reported but more lenient categorical outcome measures of response and euthymia.
Methods:  We pooled and reanalyzed results through 3 weeks from two published randomized double-blind trials of olanzapine versus placebo for treating acute bipolar mania ( 1, 2 ). Response was previously defined as ≥ 50% decrease from baseline to endpoint total Young Mania Rating Scale ( 3 ) (Y-MRS) scores, and euthymia as an endpoint total Y-MRS score of ≤ 12. In this report, remission required an endpoint total Y-MRS score of ≤ 7, and an endpoint total Hamilton Depression Rating Scale, (HAM-D21) ( 4 ) score of ≤ 7 and an endpoint Clinical Global Impression Scale – Bipolar version, CGI-BP ( 5 ), overall severity score of ≤ 2.
Results:  Olanzapine treated subjects achieved statistically significantly greater rates of clinical response, euthymia and remission than those assigned to placebo, 55% versus 29.5%, 50% versus 27%, and 18% versus 7%, respectively.
Conclusions:  Olanzapine monotherapy resulted in discernable clinical improvements in mania in over 50% of subjects and just under 20% of subjects achieved a near complete resolution of manic and accompanying depressive symptoms after 3 weeks of treatment. Full remission is an important but potentially elusive goal during short-term management of acute mania.