July 22, 2010

Deep brain stimulation study of Parkinson’s gains extension

Featured Image

David Charles, M.D.

Deep brain stimulation study of Parkinson’s gains extension

A study testing the application of deep brain stimulation (DBS) in early-stage Parkinson's disease has been extended for three years, giving researchers more time to collect crucial data.

The study, led by David Charles, M.D., vice-chair of Neurology, and Pete Konrad, M.D., Ph.D., associate professor of Neurosurgery, has followed 30 patients recently diagnosed with Parkinson's for two years.

Medtronic, the DBS device manufacturer, has offered funding to extend the evaluation period to five years.

“We are the only center in the world leading a study of DBS in early Parkinson's disease, and thus the only center gathering intraoperative neurophysiology data,” Charles said. “No other center is operating at this early stage in the disease process and our intraoperative data will provide critical information in the understanding of how Parkinson's disease advances.

“The longitudinal data from these additional three years will help us also better understand the progression of Parkinson's disease when treated early with DBS.”

Parkinson's disease is a progressive motor system disorder, caused by the brain's inability to produce a sufficient amount of the chemical dopamine. This results in an unexplained neurodegeneration, leading to tremor, slow movement, stiffness and difficulties with balance and walking.

The DBS device involves a thin wire implanted into an area deep in the brain. The wire runs to a small pulse generator implanted just under the collarbone, similar to a heart pacemaker, which emits an electrical current.

The original study, under way since 2006, randomized patients diagnosed with early-stage Parkinson's disease into groups receiving DBS or standard of care to test that DBS is safe and well tolerated in order to launch a large-scale, multi-center trial.

The safety and tolerability of DBS is being studied in the first two years of the study, and Charles said the extension could actually yield results showing a positive clinical effect on the natural history of Parkinson's disease when treated early with DBS.

“We're trying to see if DBS could change the progression of the disease. There is currently no therapy proven to slow the progression. Current treatments only help the symptoms, and do not slow the degeneration of the brain,” Charles said.

“But we feel that enrollment has been so robust, that if our subjects continue with us through the five years, we might be able to detect real effects of DBS.”

Charles attributes the success of the study to the multi-disciplinary approach.

“Vanderbilt is an ideal environment to lead such a study because of the collaborative sprit among our faculty. Psychiatry, neurology and neurosurgery have a tremendous record of successful collaborations for research, patient care and education,” he said.