Transcranial direct current stimulation therapy for bipolar depression
Research type
Research Study
Full title
Community-based transcranial direct current stimulation treatment for bipolar depression
IRAS ID
308690
Contact name
Cynthia Fu
Contact email
Sponsor organisation
University of East London
Duration of Study in the UK
1 years, 5 months, 27 days
Research summary
Research Summary
Individuals with bipolar disorder spend more time depressed than manic or hypomanic. However, there are fewer treatments for bipolar depression than for the manic phase. It usually takes weeks to months of trial and error to find the right treatment or combination of treatments, and they usually have side effects.
Transcranial direct current stimulation (tDCS) is a potential new treatment for bipolar depression. In tDCS, a mild current is generated by two small metal discs through a headband that is worn over the forehead. The current makes it easier for brain cells to discharge or to fire. tDCS does not trigger brain cells to discharge directly, and it does not cause a seizure like ECT.
Research studies have found that a course of tDCS sessions can help to improve depression. However, most studies have given tDCS in a research clinic. This is a problem because the treatment involves daily visits for a few weeks.
As tDCS is a portable and safe, it can be given at home. In our research, we have been giving tDCS to individuals with depression while they have been at home and with a study team member present at each session by video call. We have found that a course of tDCS treatment helps to improve depression. Importantly, participants like having the tDCS sessions at home and would recommend the treatment.
The most common side effects have been tingling feelings and itchiness, mild redness on the forehead, which lasts for a short while, and a few participants have noticed a mild headache.
For this project, we will look at whether tDCS can help individuals with bipolar disorder who are currently suffering from depression. We will provide a course of tDCS treatment at home with a study team member present at each visit by video call. Each session is 30 minutes, and there are 5 sessions a week for 3 weeks and then 2 sessions a week for another 3 weeks.
We will look at how depressive symptoms improve with the treatment and how participants feel about having the sessions at home. Findings from this project will offer a potential new first-line treatment for bipolar depression.
Summary of Results
Who approved the study?
The study was approved by London Fulham Research Ethics Committee (21/LO/0910) and was registered on a clinical trials registry called clinicaltrails.gov (NCT05436613).
What was the study about?
We looked at how individuals with bipolar depression feel about using tDCS at home. We wanted to understand how easy it is to use, how often any side effects happen, and whether it could help improve their depression symptoms.
When did the study take place?
The study started in May 2022 and ended in May 2024.
Who were the participants?
In total, 44 individuals with bipolar depression took part. There were 31 women and 13 men. The average age was 47 years. Participants came from all over England and Wales.
What were the study findings?
Almost all the participants completed the full 6-week course of sessions (41 out of 44 participants (93%)), and most participants came to the follow up visit at 5 months (32 participants (73%)).
After the course of sessions, most participants (34 participants (77%)) showed an improvement in their depressive symptoms. This was measured by an improvement in depressive symptoms which was 50% or greater as compared to when they had started, based on the questionnaires at the sessions. As well, nearly half the participants said that they felt that they were back to their usual self with very few depressive symptoms (21 participants (48%)).
After 5 months, most participants said that they continued to have improved symptoms (20 out of 32 participants (63%)), and almost half the participants said that they had very few depressive symptoms (13 participants (40%)).
The most common side effects were skin tingling, an itching or burning sensation, and skin redness after the stimulation. Less common side effects included headache, sleepiness and scalp pain. Most side effects were mild rated as being mild (91%), some side effects were rated as moderate severity (9%) and only two reports of side effects were rated as severe (0.4%); one instance of tingling and one instance of burning sensation. No participants reported burns on their skin. Serious adverse events are side effects that are life threatening or require the individual to have to go to hospital. There were no serious adverse events.
Everyone who completed the course of sessions said that they found it acceptable.
We also asked participants to complete some paper tasks before and after having the course of tDCS sessions to look at how it could have affected attention and remembering things. We found that after the course of sessions participants were better at remembering a list of words than they were before they had the course of sessions. This suggests that the tDCS sessions might have helped to improve some learning and memory.
What were the EEG findings?
We also asked participants to use a second device at the start and end of the study. This device was a headband that went across the forehead and behind the ears. The device records brain activity and is called an electroencephalogram (EEG). We took these recordings to see if there were any changes in brain activity before and after the course of tDCS sessions.
We found some changes the brain activity in participants who had more improvements in their depressive symptoms. These changes showed that there was more brain activity happening in different areas of the brain at the same time, working together at the same time.
What do the results mean?
We found that most people with bipolar depression found the tDCS device easy to use and liked having the sessions at home. We found that tDCS helped to improve depressive symptoms for many individuals, but it did not help everyone. We also found that it was safe to use with mild side effects for most participants.
Where have the results been published?
We shared these findings with the wider medical and research community by publishing them in scientific journals. You can follow the links to read the full published article, the brain activity EEG results article, and the results of the pen and paper tasks article.
What’s next?
Everyone in this study received active tDCS treatment. To see if the improvements are related to active tDCS, we will be comparing active tDCS with 'inactive' tDCS in a follow up study.
REC name
London - Fulham Research Ethics Committee
REC reference
21/LO/0910
Date of REC Opinion
16 Feb 2022
REC opinion
Further Information Favourable Opinion