April 28, 2010 — Deep brain stimulation offers a clear benefit to patientswith advanced Parkinson’s disease in terms of symptom control and quality oflife, but as with any surgery, the procedure is not without risks, new researchconfirms.
The study is the second major trial in a little over a year to find deepbrain surgery and medication to be better thanmedication alone for reducing the movement-related symptoms that worsen asParkinson’s progresses.
The surgery has been used for over a decade to treat advanced Parkinson’sdisease, but few studies have directly compared it to standard nonsurgicaltreatments.
The procedure involves the placement of electrodes deep within the brainthat deliver stimulation to block the electrical signals that causeParkinson’s-related movement disorders. A battery-operated device implantedunder the skin, which is similar to a heart pacemaker but smaller,controls the stimulation.
Pros and Cons of Surgery
The new study included 366 patients in the U.K. with advanced Parkinson’sdisease who were treated with either deep brain stimulation and medication ormedication alone.
A year after roughly half the patients had the surgery, all completed adetailed questionnaire designed to measure quality of life, symptoms,functional ability, and emotional and intellectual status.
The responses showed that surgically treated patients had better mobility,less discomfort, and were able to perform day-to-day activities better thanpatients who did not have the surgery, study co-author Keith Wheatley, DPhil,of the U.K.’s University of Birmingham tells WebMD.
Roughly three-fourths of patients in both treatment groups initially citedthe involuntary, jerky body movements known as dyskinesia as a reason forconsidering surgery.
A year later, almost half of the surgically treated patients (48%) reportedhaving no dyskinesia symptoms during the day, compared to 14% of patients whodid not have the surgery.
And 29% of the surgery patients reported being in complete control of motormovements throughout the day, compared to just 3% of patients treated only withdrugs.
Surgically treated patients did experience more treatment-relatedcomplications. One in five reported serious treatment-related adverse events,and one patient died during surgery. The most common surgical complication wasinfection.
The study appears in the April 29 issue of Lancet Neurology.
“The risks were no greater than what you would expect to see with anysurgery,” Wheatley says. “But patients need to understand the benefits andrisks of this surgery so that they can make an informed decision about it.”
‘Many Who Could Benefit Aren’t Getting Surgery’
The patients who took part in the U.K. trial all had symptoms thatcould no longer be controlled with drugs alone, and most Parkinson’s patientswho have the surgery also have advanced disease.
Neurologist Michael Okun, MD, who serves as medical director for theNational Parkinson Foundation, tells WebMD that about 10% to 20% of Parkinson’spatients have symptoms severe enough to qualify for surgery.
But he adds that a large percentage of patients who are good candidates arenot getting the surgery.
He says studies like the U..K trial and a Veteran’s Administration trialpublished last year may help change that.
In that study, surgically treated patients followed for six months reportedbetter symptom management and quality of life than patients treated with drugsalone.
Okun co-directs the Movement Disorders Center at the University of Floridaat Gainesville.
“There is more and more evidence that for the right patient, surgery canmake a huge difference in symptoms and quality of life,” Okun says. “But we arestill missing a lot of people who do qualify and could benefit.”