Treating bipolar disorder, patients with mixed episodes are considered the most problematic subgroup as they do not respond easily, which makes the choice and dosage of the respective pharmacotherapy difficult. One objective of this ongoing 18-months, prospective multicenter, non-interventional study on mood-stabilizing therapies is to find out what specific patient features are associated with mixed episodes.

Observational data from 761 outpatients are collected by 150 office or hospital based psychiatrists throughout Germany in the course of standard treatment for bipolar disorder. A baseline analysis was run and patients without mixed episodes (0-MX) were compared to those with one (1-MX) and more (>1-MX) mixed episodes.

30.9% patients experienced mixed episodes within the last 12 months, with a hospitalization rate of 33.2% for the 0-MX, 36.5% for the 1-MX and 43.4% for the >1-MX group. The 0-MX group had 5.6% rapid cyclers, while it was 11.0% for the 1-MX and 32.8% for the >1-MX group. Regarding treatment, 0-MX mostly receive anticonvulsive monotherapy (31.1%), 1-MX olanzapine monotherapy (31.8%) and >1-MX anticonvulsive monotherapy (35.3%). A higher psycho-education rate appeared with the 1-MX (19.0%) and >1-MX (28.8%) than with the 0-MX group (14.8%). Further psychotic diseases were associated with less mixed episodes (0-MX: 71.3%, 1-MX: 69.2%, >1-MX: 57.5%).

The high hospitalization rate suggests the need for a careful medical monitoring and optimized pharmacotherapy to prevent bipolar relapse in patients with mixed episodes. The present data reveal a want for more detailed analysis.