BOSTON– Early results from an industry-funded registry of Parkinson’s disease patients who underwent deep brain stimulation (DBS) reveal that their quality-of-life scores grew by 22% at 6 months.
Patients, their caregivers, and their clinicians all overwhelmingly reported improvement.
The study, which examined two types of technology that are not approved in the United States, aims to fill a gap in DBS research: How do patients fare in normal conditions – “real life” – outside of clinical trials?
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While DBS has been widely used for many years, “much of the available information is from controlled trials that usually select the best possible patients – relatively young and in the condition to go through a clinical trial. There’s less information about people who may not be in the best possible shape,” said Michele Tagliati, MD, professor and director of movement disorders at Cedars-Sinai Medical Center in Los Angeles. He did not take part in the study but is familiar with its findings.
The study’s lead author, Günther Deuschl, MD, PhD, of University Hospital Schleswig-Holstein, released preliminary findings at the annual meeting of the American Academy of Neurology.
The researchers have enrolled 203 patients who were treated with Boston Scientific’s Vercise DBS system, which is not approved for use in the United States. The researchers plan to track patients for 3 years.
“This is the first such industry-sponsored registry, which addresses a need in the field to track DBS practice and outcomes across multiple centers,” said Mark Richardson, MD, PhD, associate professor and director of epilepsy and movement disorders surgery at the University of Pittsburgh Medical Center. He did not take part in the study but is familiar with its findings.
The average age of participants is 59 years, which Dr. Deuschl said is a bit younger than many other studies, and 69% are male. Eighty-five serious adverse events were reported in 52 patients; 57 were not linked to the procedure. One patient died of a surgery-related hematoma.
At 6 months, patients reported a 22% improvement (P less than .0001) on the Parkinson’s Disease Questionnaire (PDQ-39), Dr. Deuschl said, and that level was sustained at 1 year.
That level of improvement is significant, Dr. Richardson said in an interview.
“Previous randomized, controlled trials have shown that patients who are candidates for DBS but who continue medical management alone are most likely to have no improvement at all on any quality of life measures,” he said. In addition, “6 months is fairly short, and some patients likely have not reached stable stimulation programming and effectiveness.”
The researchers also reported that more than 90% of patients, their clinicians, and their caregivers reported improvement.
This kind of study is valuable in light of skepticism about DBS, which is used to treat patients who do not respond to medication, Dr. Tagliati noted.
“Despite 15 years of [Food and Drug Administration] approval, there is still some form of resistance out there in referring patients with Parkinson’s at the right time when they can still fully benefit from the procedure,” he said. “Registries have this potential great benefit in terms of awareness and reassuring people.”
As for the high rating of improvement, Dr. Tagliati said it reflects what he sees in the clinic.
“Barring complications, we have very substantial satisfaction in our patients, definitely in the short term after DBS,” he said. “Over the long term, the picture is more difficult to read.”
Dr. Deuschl said researchers would like to add hundreds more patients to the study, and they hope to gain data about the differences between the results from standard and directional-lead DBS systems.
Boston Scientific funded the study, and some of the authors work for the company.
Dr. Richardson reported receiving research grant funding from Medtronic. Dr. Tagliati reported receiving funding from Abbott, Boston Scientific, Medtronic, and all DBS manufacturers, and his clinic is an investigational center for the Vercise DBS system. Dr. Deuschl reported receiving consulting fees from Boston Scientific, grant funding from Medtronic, lecture fees from Almirall and Novartis, and royalties from Thieme Publishers.