Transcranial Direct Current Stimulation Therapy for Bipolar Depression

Bipolar disorder is a severe and disabling disorder. The course of illness is often progressive but is highly heterogeneous between individuals and within the lifetime for an individual. The most common treatments are medications. However, for many individuals, combinations of medications are often required, and full recovery is infrequent. The novel brain stimulation treatment, transcranial direct current stimulation (tDCS), is a potential first-line treatment for bipolar depression. The present research question is whether tDCS can be provided as a home-based treatment for bipolar depression for adults with bipolar disorder.

The novel brain stimulation treatment, transcranial direct current stimulation (tDCS), is a potential first-line treatment for bipolar disorder. tDCS generates a small electric current which modulates how easy it is for active brain cells to discharge. The device is a headband worn over the forehead with two electrodes, which are small metal discs, where the current comes from. tDCS does not directly stimulate brain cells to cause a seizure like electroconvulsive therapy (ECT) and it does not induce brain cells to discharge like transcranial magnetic stimulation (TMS). Clinical studies have shown that tDCS treatment could help to improve the symptoms of depression. The main side effects have been redness, skin irritation or sensations (itching, tingling or burning) under the electrodes. Less commonly reported side effects include headache or tiredness. tDCS is a portable and safe treatment. The studies to date have mostly looked at tDCS treatment which has been provided in a research setting. This is a problem because the treatment requires daily sessions for several weeks which could limit whether individuals would be able to go every day. As tDCS is a portable and safe treatment, it could be provided in the community. The present study is a proof-of-concept trial to assess the efficacy, acceptability and safety of tDCS treatment for bipolar depression within a community-based setting.

6-week course of active tDCS treatment, consisting of 5 sessions per week for the first 3 weeks followed by 2 sessions per week for 3 weeks, for a total of 21 tDCS sessions. The duration of each session is 30 minutes.

tDCS at 2mA in 30 minute sessions for 5 sessions per week for 3 weeks and then 2 sessions per week for 3 weeks.

As measured by clinician-rated MADRS score improvement of >= 50% following the course of tDCS treatment

Inclusion Criteria: diagnosis of bipolar disorder based on DSM-5 criteria minimum score of 18 on the MADRS being on a stable dosage of mood stabilizing medication for a minimum of two weeks Exclusion Criteria: comorbid psychiatric disorder significant risk of suicide or self harm any contraindications to tDCS, including implanted electronic medical devices history of epilepsy

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