Brain Stimulation Effective for Parkinson's
Offers greater benefits, fewer side effects than drugs, study reports
WEDNESDAY, Aug. 30, 2006 (HealthDay News) -- Deep brain stimulation -- a surgical procedure to reduce Parkinson's symptoms -- is more effective for patients with advanced disease than medication and may have fewer side effects than drugs do.
Those are the conclusions of a new study that found nearly a 25 percent improvement in symptoms in those undergoing deep brain stimulation while the medication group stayed the same.
"Deep brain stimulation improves the quality of life in patients with advanced Parkinson's disease at a stage when medical treatment is no longer able to improve quality of life," said the study's lead author, Dr. Guenther Deuschl, professor of neurology and chairman of the department of neurology at Christian-Albrechts University in Kiel, Germany.
"It is important that the time during which these (deep brain stimulation) patients were immobile decreased highly significantly, the time with good mobility increased, and the sleep time also increased," he said.
The study results were expected to be published in the Aug. 31 issue of the New England Journal of Medicine.
Parkinson's is a chronic and progressive movement disorder that causes tremors, stiffness, slowness of movements, and impaired balance and coordination. About one million Americans have Parkinson's disease, according to the Parkinson's Disease Foundation. Another 40,000 are diagnosed with the disease each year.
Deep brain stimulation is a procedure generally reserved for people with severe Parkinson's symptoms and for those who no longer get much relief from medications. The procedure involves placing a thin wire that can carry electrical currents deep within the brain.
For this study, the wire was placed in the subthalamic region of the brain. The wire was then attached to a deep brain stimulator, which sends an electrical current to that area of the brain. This temporarily shuts down the activities of the brain cells in that area of the brain, according to information from the Parkinson's Disease Foundation. Deep brain stimulation doesn't cure Parkinson's disease but temporarily blocks the abnormal signals sent by the brain that cause tremors and other symptoms.
For the study, researchers in Germany and Austria recruited 156 people with advanced Parkinson's disease. All were under 75 years old. The patients were randomly assigned to receive either deep brain stimulation or medications.
The patients were assessed at the start of the study, and then again after six months of treatment, using standard Parkinson's assessment tools. These tools included the Parkinson's Disease Questionnaire, which assigns a score between 0 and 100, and the Unified Parkinson's Disease Rating Scale, with scores between 0 and 108 to assess the severity of symptoms. The higher the score, the worse the symptoms, according to the study.
After six months, people selected for deep brain stimulation lowered their scores on both the PDQ and the UPDRS, by 9.5 points and 19.6 points, respectively. Those in the medication group remained nearly the same over the six-month study period.
Serious adverse events were more common for the deep brain stimulation group than the medication group -- 13 percent versus 4 percent. One person in the stimulation group suffered a fatal brain hemorrhage. But, overall, the frequency of adverse side effects was more common in the medication group compared to the stimulation group -- 64 percent versus 50 percent.
"While there were certain complications for surgery, overall there seemed to be more complications in the medicine group," noted Dr. Michael Kaplitt, director of movement disorder surgery at Weill Cornell/New York Presbyterian Hospital in New York City.
"This raises an interesting question: Should we consider surgery in earlier stages because of the fact that ongoing medical therapy might not be benign?" said Kaplitt, who added that there are studies looking at using deep brain stimulation in earlier stages of Parkinson's.
He said the new study confirms what neurosurgeons are already seeing in practice.
"While surgery can be frightening to many people -- understandably -- with a disease such as Parkinson's, it can be extraordinarily beneficial in the proper patient," Kaplitt said.
To learn more about deep brain stimulation for Parkinson's disease, visit the National Institute of Neurological Disorders and Stroke.