Deep brain stimulation to ease depression
By Liz Lockhart
Some months ago Mental Healthy reported on a pace-maker in the brain which provides brain stimulation 
as a treatment for mental health disorders. We have also reported on this type of treatment for schizophrenia sufferers.
More recently a newly published Canadian pilot study supports the use of deep brain stimulation (DBS) for major depressive disorder for patients who have not responded to traditional treatments.
Researchers found that DBS therapy provided a noticeable improvement in depression symptoms and increased the overall quality of life for patients who had not previously responded to other treatment. The DBS therapy targeted an area of the brain known as Brodmann Area 25.
‘The reduction in depression scores is clinically significant as these patients had previously tried multiple medications, psychotherapy and/or electroconvulsive therapy (ECT) without success,’ said Andres Lozano, M.D., neurosurgeon at Toronto Western Hospital, author of the paper and a primary investigator in the study.
Deep brain stimulation has been used effectively for other conditions such as Parkinson’s disease and essential tremor, but has not yet been approved in America for treating depression. Electrical impulses course through electrodes implanted in the brain, where they are believed to affect brain cells and neurochemical transmitters.
For the purpose of this study 21patients were enrolled. Each had, on average, suffered from depression for more than 20 years, were considered disables or unable to work at the time of enrolment, and had tried more than 16 depression medications.
The researchers discovered that after one year os DBS treatment 62% of all the patients in the study had a 40% reduction in symptoms and 29% had symptoms reduced by 50% compared to their symptoms at the start.
Lozano said ‘To see 62% of the patients in this study respond at one year gives us hope that this research may lead to a therapy for this hard to treat patient population.’
Prior to the DBS treatment 70% of the participants were categorised as severely or extremely ill, using a Clinical Global Impression of Severity rating scale that measures the extent of their illness. After just 12 months of DBS, over 80% of the patients experienced improvement and none of the patients were rated as severely or extremely ill.
Also, eight of the study patients returned to daily activities which included returning to work or school and sustaining relationships with family and friends. Two patients were deemed to be in remission.
‘These findings are significant as they confirm the basis on which we established the Broaden pivotal study. These results add to the growing evidence suggesting that DBS therapy may help patients who currently don’t have an adequate treatment option in managing severe depression,’ said Rohan Hoare, Ph.D., president of St. Jude Medical Neuromodulation Division.
The study is published online in the Journal of Neurosurgery and was conducted at three research facilities in Canada.
Source: St Jude Medical
