Lithium, valproate, and carbamazepine prescribing patterns for long-term treatment of bipolar I and II disorders: A prospective study

Abstract

Objective: This study aims to describe the prescription patterns of the mood stabilizers most commonly used for the treatment of bipolar I and II disorders (lithium, valproate, and carbamazepine) and to analyze the treatment outcomes.

Methods: Two hundred and thirty-four outpatients with bipolar disorders receiving prophylactic treatment with lithium, valproate, carbamazepine, or their combination were followed up for at least 18 months in two Italian psychiatric centers specialized in mood disorders.

Results: The combination of lithium and valproate or carbamazepine was the most common prophylactic treatment (54.3%), followed by valproate or carbamazepine (24%) and lithium monotherapy (22%). Polytherapy was prescribed mainly to patients with bipolar I disorder, a high number of previous episodes and lifetime psychotic symptoms, whereas valproate or carbamazepine monotherapy was prescribed to patients with anxiety comorbidity. The annual frequency of recurrences decreased significantly after entering the study in the overall sample, and the reduction was significantly higher in patients on lithium plus valproate or carbamazepine compared with the valproate or carbamazepine group, but not with the lithium monotherapy group. The number of mixed recurrences during the follow-up was significantly higher in patients on lithium plus valproate or carbamazepine.

Conclusions: Our findings may help clinicians to personalize long-term treatment to prevent relapses of bipolar disorder according to clinical presentation.

Keywords: bipolar disorder; long-term treatment; mood stabilizers; naturalistic study; polypharmacy.