Declaration of interest
A.K. declares that, over the past 36 months, she has received lecture honoraria from Eli Lilly Sweden. M.L. declares that, over the past 36 months, he has received lecture honoraria from Biophausia Sweden, Servier Sweden, AstraZeneca. G.M.G. has held grants from Servier, received honoraria for speaking or chairing educational meetings from Abbvie, AZ, GSK, Lilly, Lundbeck, Medscape, Servier, and advised AZ, Cephalon/Teva, Lundbeck, Merck, Otsuka, P1vital, Servier, Sunovion and Takeda, and holds shares in P1vital.
Clinical trials have examined the efficacy of drugs to prevent relapse in patients with bipolar disorder, however, their design often limits generalisation to routine clinical practice.
To estimate the effectiveness of drugs used for maintenance treatment in bipolar disorder.
We used national registers to identify 35 022 individuals diagnosed with bipolar disorder and information on lithium, valproate, carbamazepine, lamotrigine, quetiapine and olanzapine treatment from 2006 to 2009. The main outcome was psychiatric hospital admissions. We used stratified cox regression to compare periods on and off medication within the same individual.
Medication with lithium, valproate, lamotrigine, olanzapine and quetiapine was associated with reduced rates of admission to hospital. Lithium was more effective than quetiapine and olanzapine. The effects of specific drugs depended on the polarity of the mood episode.
Our findings complement results from randomised controlled trails, but suggest that lithium is more effective than both quetiapine and olanzapine in routine clinical practice.
- © The Royal College of Psychiatrists 2017.