A Literature Review of Comparative Effectiveness of Subthalamic Nucleus Versus Globus Pallidus Interna Deep Brain Stimulation with Modeled Adjunctive Traditional Chinese Medicine Interventions

Abstract

Background

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi) are established treatment options for advanced Parkinson’s disease; however, their comparative efficacy on long-term outcomes remains uncertain. Traditional Chinese medicine (TCM) modalities such as acupuncture, herbal medicine, and moxibustion have shown potential as adjunctive therapies to standard care in improving motor and non-motor symptoms. This literature-based review compares the effectiveness of STN versus GPi DBS and evaluates any additional benefit of TCM adjuncts.

Methods

Randomized controlled trials comparing STN and GPi DBS were identified from peer-reviewed publications, with key data extracted from the New England Journal of Medicine Trails multicenter trial (n = 299) and the Neurostimulation for Parkinson’s Disease Study trial (n = 128). Outcome measures included Unified Parkinson's Disease Rating Scale (UPDRS) part III (off medication), levodopa equivalent daily dose (LEDD), executive function, and adverse events at 12 and 36 months. Effects of TCM adjuncts were drawn from meta-analyses of randomized trials evaluating acupuncture and related interventions as add-ons to conventional therapy. Inclusion and exclusion criteria matched those of the anchor DBS trials, and pooled estimates from the literature were narratively reviewed.

Results

Across 427 patients in DBS trials, both targets significantly improved UPDRS III scores off medication, with STN showing a modestly greater reduction at 36 months. STN patients demonstrated greater LEDD reduction compared with GPi, while cognitive and mood outcomes favored GPi in some measures. Adverse event rates were comparable between the two treatment targets. Meta-analytic evidence of TCM adjuncts (25–27 randomized trials, n = 1,616–2,314) indicated additional improvements in UPDRS total and part III scores when combined with conventional therapy. Overall evidence suggests that such adjunctive TCM interventions could enhance motor outcomes following either DBS target, although direct post-DBS RCTs are lacking.

Conclusion

Both STN and GPi DBS provide durable motor benefits in advanced Parkinson’s disease, with STN offering greater medication reduction and GPi showing relative cognitive preservation. Evidence supports the potential role of TCM modalities as adjuncts to standard care, warranting further investigation in post-DBS populations through well-designed randomized trials.