Pharmacotherapeutic trends in 2231 psychiatric inpatients with bipolar depression from the International AMSP Project between 1994 and 2009

Abstract Background Pharmacological treatment of bipolar depression is a complex and controversial issue, and its real-world practice remains largely unknown. Method Observational analysis of the pharmacotherapy of 2231 psychiatric inpatients with a current episode of bipolar depression. The study was based on cross-sectional prescription data from European psychiatric hospitals that had been repeatedly collected between 1994 and 2009 through the collaborative Drug Safety in Psychiatry (AMSP) program. Results Overall 81.3% of patients received antidepressants (AD) (7.8% monotherapy), 57.9% antipsychotics (AP), 50.1% anticonvulsants (AC), 47.5% tranquilizers, and 34.6% lithium (Li). Use over time was stable for AD, decreased for Li, and increased for AC, AP and tranquilizers. Pronounced increases were specifically observed for quetiapine, lamotrigine and valproate. Use of tricyclic AD decreased but its prevalence was still 11.8% in 2009. Venlafaxine was used by 19.5% in 2009. We also observed an increase of polypharmacy combining AD, AP, AC and Li. From 2006 to 2009 37.0% received concomitant treatment with three, and 6.4% even with all four of those drug classes. Limitations Observational cross-sectional study without follow-up or additional clinical information. Conclusions Monotherapy with antidepressants and any use of tricyclic AD and venlafaxine still has a considerable prevalence in bipolar depression, but this is controversial due to the reported risk of treatment emergent affective switches. Triple and quadruple therapy is not evidence-based but increasingly used in clinical practice. This may reflect an attempt to overcome treatment failure, and further studies should evaluate efficacy and safety of this common practice.