Deep brain stimulation improves motor function and reduces levodopa needs in Parkinson's disease patients regardless of GBA mutation statusDeep brain stimulation helps Parkinson's patients but GBA mutation carriers face faster cognitive decline

Neurosurgical review Published May 20, 2026 Study authors: Gonzales Romero Patrick Fabrizio, Bermejo Rosado Pierina, Paredes Torres Fabiana, Váscones-Román Fri… PubMed ↗ DOI ↗ Editorial oversight: Dr. Ji-eun Park, MD · Brain, Mind & Pain

AI-generated summary of the cited source, checked by automated accuracy review. How we work

Key Takeaway

DBS improves motor function and reduces levodopa needs in Parkinson's patients, though GBA mutation carriers face greater long-term cognitive decline.

This meta-analysis of observational studies examined deep brain stimulation in Parkinson's disease patients with and without GBA mutations. The intervention consistently improved motor function when patients were not taking medication. Additionally, these patients sustained reductions in their levodopa equivalent daily dose throughout the study period.

When comparing groups, no significant differences emerged between GBA mutation carriers and non-carriers regarding motor outcomes or medication needs. Both groups benefited similarly from the surgical procedure in terms of movement control and drug reduction.

Cognitive performance showed a different trajectory over time. All patients experienced some decline, but those with GBA mutations demonstrated greater deterioration at the five-year mark. This suggests a specific vulnerability in mutation carriers that clinicians should monitor closely.

The findings highlight the dual nature of the treatment: robust motor benefits for everyone, but distinct cognitive risks for specific genetic subgroups. Practitioners must weigh these long-term cognitive implications when considering surgery for patients with known GBA mutations.

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.

What this means for you:

GBA mutation carriers with Parkinson's showed faster thinking decline after deep brain stimulation surgery.

Study Details

Study typeMeta analysis

EvidenceLevel 1

PublishedMay 2026

PMID42156595

View Original Abstract ↓

Deep brain stimulation (DBS) is an established therapy for motor complications in Parkinson's disease (PD). Patients carrying glucocerebrosidase (GBA) mutations exhibit distinct disease trajectories, raising questions regarding potential differences in clinical outcomes following DBS compared with non-carriers. To evaluate short- and long-term motor, medication, and cognitive outcomes following DBS in patients with GBA-PD compared with non-GBA PD. We conducted a systematic review and meta-analysis of studies reporting clinical outcomes in PD patients with and without GBA mutations who underwent DBS and had a minimum follow-up of one year. Random-effects inverse variance models were applied, with subgroup analyses according to GBA status. DBS was associated with significant improvements in motor function in the off-medication state and sustained reductions in levodopa equivalent daily dose in both GBA carriers and non-carriers, with no significant between-group differences. Cognitive performance declined over long-term follow-up in both groups. At five years, greater cognitive decline, assessed using the Mattis Dementia Rating Scale, was observed among GBA-PD mutation carriers compared with non-carriers. Motor improvement and medication reduction following DBS were comparable between PD patients with and without GBA mutations. Over long-term follow-up, greater cognitive decline was observed among GBA-PD carriers.

Deep brain stimulation improves motor function and reduces levodopa needs in Parkinson's disease patients regardless of GBA mutation statusDeep brain stimulation helps Parkinson's patients but GBA mutation carriers face faster cognitive decline

Study Details

Intravenous tenecteplase improves functional outcomes but increases hemorrhage risk in non-large vessel occlusion acute ischemic stroke

Tenecteplase improves stroke recovery but increases bleeding risk in late treatment window

Clinical research that matters. Delivered to your inbox.

Deep brain stimulation improves motor function and reduces levodopa needs in Parkinson's disease patients regardless of GBA mutation statusDeep brain stimulation helps Parkinson's patients but GBA mutation carriers face faster cognitive decline

More on Parkinson's Disease

Study Details

Intravenous tenecteplase improves functional outcomes but increases hemorrhage risk in non-large vessel occlusion acute ischemic stroke

Tenecteplase improves stroke recovery but increases bleeding risk in late treatment window

Clinical research that matters. Delivered to your inbox.

Related in Neurology

From Other Specialties