Maintenance therapies in bipolar disorder: focus on randomized controlled trials

Area of Science:

• Psychiatry
• Pharmacology
• Clinical Neuroscience

Background:

• Lithium is the established first-line treatment for bipolar disorder maintenance therapy.
• Growing use of alternative agents necessitates a review of current evidence.
• Limitations of lithium monotherapy include non-response and side effects, highlighting the need for alternatives.

Purpose of the Study:

• To review double-blind, placebo-controlled studies on the efficacy of lithium and other mood stabilizers.
• To compare the prophylactic effects of lithium, carbamazepine, divalproex, lamotrigine, and olanzapine.
• To assess the role of monotherapy versus combination therapy in bipolar disorder management.

Main Methods:

• Systematic literature review using Medline database.
• Keywords included: bipolar disorder, controlled trials, mood stabilizer, lithium, lamotrigine, divalproex, olanzapine, carbamazepine.
• Emphasis on double-blind, placebo-controlled studies.

Main Results:

• Lithium remains the gold standard for preventing manic/hypomanic relapse and shows the greatest antidepressant effect among antimanic mood stabilizers.
• Lamotrigine is well-supported for acute and prophylactic management, particularly effective in preventing depressive episodes and in rapid-cycling bipolar II disorder.
• Carbamazepine may be an alternative for specific patient profiles, but data is equivocal; atypical antipsychotics like olanzapine show emerging support.

Conclusions:

• Monotherapy is often inadequate for long-term bipolar disorder management, necessitating combination therapy as the standard of care, especially for treatment-refractory cases.
• Combination therapy is crucial for maintaining remission in most patients, even those initially on monotherapy.
• Further controlled trials comparing combination therapies are needed, utilizing survival analysis techniques.