Hermitage resident Stephen Purcell, 70, has had Parkinson’s disease for a long time.
He knew something was wrong as far back as 2008. He had been diagnosed at Summit Medical Center in Hermitage and then came to Vanderbilt University Medical Center for a second opinion. Shortly after, there was a family reunion on his wife Patsy’s side, and her cousin was a neurologist at Mayo Clinic. She asked her if she could talk to her about what she had observed from watching Stephen at the party.
“She said, ‘I know he has Parkinson’s.’ And this was the first time I met her,” Purcell said. “She could tell by the way I carried myself and my lack of expression. It was amazing that she knew. The one thing that concerned me most about it was that the kind of accepted mortality back then was that people would survive maybe 10 years.”
In 2008 at VUMC there were a group of doctors trying something unheard of on a handful of patients who signed up for their study. Half would receive deep brain stimulation (DBS) surgery in attempt to slow the progression of their early-stage Parkinson’s disease, and the others would not.
Some who received the surgery did very well, and others, for some reason, didn’t have the same benefits. With Purcell, VUMC surgeon Peter Konrad, MD, hit what VUMC researchers later found is an exceptional “sweet spot” for placing DBS-leads in his brain.
“He and his wife are wonderful,” said his neurologist Fenna Phibbs, MD, associate professor of Neurology at VUMC. “He has been my patient since 2008. From a Parkinson’s standpoint he has not required much in the way of medication changes, and his stimulation levels have remained pretty darn low over time.
“We have had some challenges with some nonmotor symptoms, those that don’t respond to medications or DBS. He and his wife have been active even after retirement, which is important for the disease as well,” she said.
Parkinson’s is a relentless, progressive disease. But Purcell says he isn’t too much different today than he was in 2008.
“I am doing remarkably well. Whenever I go to any kind of meetings, when I am around other people with Parkinson’s, I see how they are struggling,” said Purcell, who will be 71 next month. “I think DBS has been a huge benefit. It has worked miracles.”
VUMC neurologists and scientists, along with colleagues from Charité-Berlin University of Medicine, recently studied patients like Purcell to determine the most effective delivery of the stimulations.
Now an Annals of Neurology study led by Mallory Hacker, PhD, MSCI, assistant professor of Neurology, with senior author David Charles, MD, professor and vice-chair of Neurology, may offer new hope to the nearly 100,000 new cases of Parkinson’s diagnosed each year.
“Parkinson’s disease is a devastating condition that is relentlessly progressive, but Dr. Hacker may have uncovered why the therapy is slowing or even stopping the progression of the motor symptoms in some of the patients,” Charles said.
“We may be able to target or plan better where to put the lead, but then, after the lead is in, have very precise stimulation to capture some areas and avoid some areas of stimulation.”
The original pilot study that included Purcell was designed to test the safety of DBS in early-stage Parkinson’s and was not sized to demonstrate efficacy or influence clinical practice. Of the 15 patients randomized to DBS, five had exceptional responses — no progression of their motor symptoms after two years.
“Deep brain stimulation — the treatment — is unique because the patient is awake, and we are testing the patient on the fly to get the electrode in exactly the right location,” Charles said. “You may have seen examples of where we have had a person here play a musical instrument, play the banjo, in the operating room as we are testing and finding just the right location for the electrodes.
“We’d been searching for a shared patient characteristic that might explain these exceptional responses to DBS, and we’d never really been able to find one until now,” he said.
The new analysis of pilot study data collected more than 15 years ago sought to determine why one-third of the patients randomized to DBS surgery experienced a halting of underlying disease progression as measured by motor symptoms.
“Dr. Hacker went to Berlin to collaborate with Dr. Andreas Horn’s laboratory, and it turned out that patients with electrodes nearer to the sweet spot were able to manage symptoms with fewer drugs and with lower stimulation settings of their implants,” Charles said.
Hacker said her study results provide a great foundation for an upcoming FDA-approved multicenter study led by Vanderbilt to determine if DBS applied in early-stage Parkinson’s will slow or stop disease progression.
Steve and Patsy can’t do all of the outside activities — boating, floating in the lake, walking on greenways — that they used to do, but they enjoy watching birds, sitting outside in the shade, and listening to music, reading books, listening to podcasts, and traveling.
“I am not as active as I used to be,” Purcell said. “But, overall, I am just doing so much better than some of the other folks I have seen with Parkinson’s. I am extremely happy I had that surgery.”
