Parkinson's disease changes how people move and think. Deep brain stimulation is a surgery that helps control shaking and stiffness. A large review looked at patients who had this surgery with and without a specific gene change called GBA. The study tracked them for at least one year and up to five years.
Patients who got the surgery saw big improvements in how well they moved without taking their daily medicine. They also needed less of their Parkinson's medication over time. These benefits held up for the full five-year period. The surgery worked well for everyone in the group.
However, thinking skills did not stay the same for everyone. All patients showed some drop in thinking ability over the long term. Those with the GBA gene change had a faster drop in thinking skills compared to others. This difference showed up clearly at the five-year mark. The study did not report exact numbers for these changes. It also did not report how many people stopped the surgery due to side effects. Because the data came from existing records, we cannot say the gene change caused the faster thinking decline. We only know the two groups differed in their results.