A new approach to brain stimulation could give people with Parkinson’s disease more control over their symptoms and halve the duration of the symptoms that bother them most, experts say.
Deep brain stimulation (DBS) is now a common treatment for people with Parkinson’s disease. It can help with symptoms such as stiffness, slowness and tremor.
This approach involves implanting fine electrodes in the brain to deliver electrical stimulation to specific areas that control movement.
Currently, this stimulation is set at a constant level, regardless of what the patient is doing or the severity of their symptoms. As a result, the technique can result in understimulation, resulting in a breakthrough of symptoms, or overstimulation, resulting in irregular movements.
Now experts say a major step has been taken in improving the technology by making it possible to automatically adjust the stimulation level to a patient’s needs, based on real-time signals in the brain.
The team behind the work say further trials are needed to confirm the pilot study results, that modifications are needed to make it feasible for routine clinical practice, and that clinicians will need training. However, they say the technology – known as “adaptive” DBS – could be widely used within a few years, with costs expected to be comparable to traditional DBS.
“Once these challenges are addressed, I am very optimistic that adaptive DBS will become a highly effective alternative to standard DBS for (Parkinson’s disease) and potentially other neurological and psychiatric conditions, providing more stable and personalized symptom control, with the potential to significantly improve patient outcomes,” said Dr. Carina Oehrn of the University of California, San Francisco, the study’s lead author.
In the journal Nature Medicine he writes: Oehrn and colleagues describe how the pilot study was conducted in four men with Parkinson’s disease who had been implanted with a DBS device provided for research by a company.
“This device can detect brain activity and provide stimulation at the same time. Our job was to create the algorithms for the software that runs on this device,” Oehrn said.
The team found that an increase in a certain type of brain signal was associated with rising dopamine levels once the participants’ drugs took effect, and with an improvement in their motor symptoms.
Oehrn said this allowed the team to create algorithms that could increase DBS stimulation when the signal was low and decrease it when the signal was high.
The team tailored the algorithms to each individual and their most bothersome symptom, resulting in a system that continuously monitored participants’ brain signals and automatically adjusted electrical stimulation based on their needs.
The four participants each received both traditional DBS and this new approach for one month, but were not told which technique was used.
Results showed that participants were approximately 50% less likely to wake up with their most bothersome symptoms with adaptive DBS compared to traditional DBS, while three out of four reported having an improved quality of life.
The team says that in addition to adaptive DBS, medications will still be needed, albeit possibly at lower doses.
“Medications are often needed to support mood and movement in Parkinson’s disease, and therefore should not be stopped altogether,” said Dr. Simon Little, another author of the study, also of the University of California, San Francisco.
Claire Bale, deputy director of research at Parkinson’s UK, welcomed the research.
“Current DBS can be life-changing, but this major step forward could help manage the varying symptoms people experience and reduce the number of side effects,” she said.
However, Bale said the study included only a small number of participants.
“The promising results support the need for larger clinical trials to confirm the safety and effectiveness of the therapy and provide the evidence needed to make ‘adaptive’ DBS a much-needed, approved new treatment for people with Parkinson’s disease,” she added.