Mixed state, since Kraepelin's pioneering contribution, refers to an affective condition in which various admixtures of depressive and manic symptoms occur simultaneously.

To evaluate the efficacy and safety of quetiapine plus ADs, both SSRIs and SNRIs in the treatment of acute mixed episodes of Bipolar I Disorder patients.

We pooled data from two ours independent studies for a total of 44 inpatients, 21 male and 23 female, diagnosed with type I mixed Bipolar Disorder (DSM-IV-TR). After receiving open-label quetiapine for 2 weeks, patients were subsequently randomised to receive either treatment with quetiapine + ADs or quetiapine alone for 18 weeks. Pooling the data, 22 received quetiapine alone (10 XRquetiapine) and the other were treated with an association of quetiapine plus an antidepressant. We evaluated these patients every week during the first month and every two weeks after that, using YMRS, HAMD-21.

The efficacy over depressive symptoms was similar in both groups. Compared with the baseline YMRS, at week 6 the percentage of improved YMRS responder was better in the group receiving quetiapine plus antidepressants than quetiapine alone. Three YMRS item scores improved significantly at week 6 in the group quetiapine plus AD(irritability, disruptive-aggressive behaviour and insomnia).

We suggest that adding an AD in order to treat every main features of mixed episode further improved the outcome, probably due to a specific action on a particular subtype of mixed state. In particular, the dysphoric subtype along with irritability and insomnia manic factors, seem to be better responsive to AD supplementation.