Brain stimulation treatments in bipolar disorder: A review of the current literature

Abstract

Objectives. Brain stimulation techniques are non-pharmacologic strategies which offer additional therapeutic options for treatment-resistant depression (TRD). The purpose of this paper is to review the current literature regarding the use of brain stimulation in resistant bipolar disorder (BD), with particular reference to hypomanic/manic symptoms. Methods. Keywords pertaining to the brain simulation techniques used in the treatment of depression (either unipolar or bipolar) along with their role in regard to hypomanic/manic symptoms were used to conduct an electronic search of the literature. Pertinent findings were identified by the authors and reviewed. Results. Brain stimulation techniques represent a valid therapeutic option in TRD. They have been extensively studied in unipolar depression and, to a minor extent, in the depressive phase of BD, showing encouraging but often limited results. With exception of electroconvulsive therapy, the efficacy of brain stimulation in the treatment of manic symptoms of bipolar patients is still uncertain and needs to be fully evaluated. Conclusions. Brain stimulation in BD is derived from its use in unipolar depression. However, there are many important differences between these two disorders and more studies with a systematic approach need to be conducted on larger samples of bipolar patients with treatment-resistant characteristics.

Key words::

• bipolar affective disorder
• neurostimulation
• treatment-resistant depression
• transcranial magnetic stimulation
• electroconvulsive therapy

Acknowledgments

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Statement of interest

Carlo Altamura has served as a consultant or on advisory boards for Roche, Lundbeck, Merck, Astra Zeneca, Bristol Myers Squibb, Janssen-Cilag, Sanofi, Eli Lilly, Pfizer and Otzuka. Allan Young is employed by the King's College London and serves as honorary consultant for SLaM (NHS UK); he has received speaker honoraria and has served on advisory boards for all major pharmaceutical companies with drugs used in affective and related disorders; he was a lead investigator for the Embolden Study (AZ), BCI Neuroplasticity study and Aripiprazole Mania Study and an investigator in studies for AZ, Eli Lilly, Lundbeck, Wyeth; he has received grant funding (past and present) from NIMH (USA); CIHR (Canada); NARSAD (USA); Stanley Medical Research Institute (USA); MRC (UK); Wellcome Trust (UK); Royal College of Physicians (Edin); BMA (UK); UBC-VGH Foundation (Canada); WEDC (Canada); CCS Depression Research Fund (Canada); MSFHR (Canada); NIHR (UK); he has no share holdings or other financial holdings. All authors report no other affiliation or economic interest in any organization that may imply a conflict of interest with the present work.