Deep brain stimulation benefits highly treatment resistant patients with major depressive disorder

Nov 18 2011

Results from the first multi-center pilot study of deep brain stimulation (DBS) for major depressive disorder were published online today by the Journal of Neurosurgery. The study, conducted at three research facilities in Canada, was designed to replicate and build upon an earlier study by Dr. Andres Lozano and Dr. Helen Mayberg which was published in the journal Neuron in 2005. Sponsored by St. Jude Medical, Inc. (NYSE:STJ), the study demonstrates significant improvement in depression symptoms among patients who are highly treatment resistant.

“The reduction in depression scores is clinically significant as these patients had previously tried multiple medications, psychotherapy and/or electroconvulsive therapy (ECT) without success”

The results of the study showed that DBS therapy targeted to an area of the brain known as Brodmann Area 25 provided noticeable improvement in depression symptoms and increased overall quality of life in patients who typically don't respond to treatment. The study enrolled 21 patients who on average had suffered from depression for 20 years, had tried in excess of 16 depression medications and were considered disabled or unable to work at the time of enrollment.

At one year, 62 percent of all patients in the study had a 40-percent reduction in symptoms and 29 percent experienced a 50-percent reduction in symptoms as measured against their baseline which was established using the Hamilton Rating Scale for Depression.

"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 Dr. Andres Lozano, neurosurgeon at Toronto Western Hospital, author of the paper and a primary investigator in the study. "To see 62 percent 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."

Patients in the study were also evaluated using a Clinical Global Impression of Severity (CGI-S) rating scale that measures the severity of their illness. Before DBS, 70 percent of the patients were categorized as severely or extremely ill. After 12 months of DBS, over 80 percent of the patients experienced improvement and none of the patients were rated as severely or extremely ill.

Additionally, study results announced earlier at the American Psychiatric Association annual meeting reported that eight of the study patients returned to daily life activities such as work, school and sustaining relationships with family and friends, and two patients were considered to be in remission.

Participants in the St. Jude Medical-sponsored study featured in the Journal of Neurosurgery were implanted with the Libra^™ DBS system which delivers mild pulses of current from a device implanted near the collarbone to small electrical leads placed in the subcallosal cingulate (SCC) area of the brain, a structure within Brodmann Area 25.

"These findings are significant as they confirm the basis on which we established the BROADEN pivotal study," said Rohan Hoare, president of St. Jude Medical Neuromodulation Division. "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."

St. Jude Medical is currently conducting a large multi-center pivotal study at up to 20 facilities in the U.S. and internationally under a U.S. Food and Drug Administration (FDA) Investigational Device Exemption. To be eligible for the BROADEN^™ study, participants must:

• Have been diagnosed with major depressive disorder
• Be between 21 and 70 years old
• Have had first depressive episode before age 45
• Have tried at least four treatments in their current episode (for example, different medications, different combinations of medications, and/or ECT)

To locate participating centers, please visit www.BROADENstudy.com or call toll-free 866-787-4332.

According to the Journal of Neurosurgery article, the most frequently occurring serious adverse events related to DBS were skin erosion and lead extension malfunction.

Depression affects millions of patients worldwide with more than 21 million adults in the U.S. suffering from some kind of depressive disorder, according to the National Institute of Mental Health. Of these, approximately 4 million live with severe depression that does not respond to traditional treatments such as medications, psychotherapy and ECT.

Three Decades of Leading-Edge Neurostimulation Technology

For more than 30 years, St. Jude Medical Neuromodulation Division has developed new technologies to treat chronic pain and other neurological disorders. Today more than 75,000 patients in 40 countries have been implanted with St. Jude Medical neurostimulation systems. Focused on research, St. Jude Medical is developing new technologies to address a growing list of neurological disorders. Clinical studies are currently underway for Parkinson's disease, essential tremor, migraine headache, and others.

Source St. Jude Medical