The potential neuromodulatory impact of subthalamic nucleus deep brain stimulation on Parkinson’s disease progression

Abstract Introduction STN-DBS has been claimed to change progression symptoms in animal models of PD, but information is lacking about the possible neuromodulatory role of STN-DBS in humans. The aim of this prospective controlled study was to evaluate the long-term impact of STN-DBS on motor disabilities and cognitive impairment in PD patients in comparison to Best-Medical-Therapy (BMT) and Long-term-Post-Operative (POP) groups. Material and methods Patients were divided into 3 groups: the BMT-group consisted of 20 patients treated only with pharmacotherapy, the DBS-group consisted of 20 PD patients who underwent bilateral STN-DBS (examined pre- and postoperatively) and the POP-group consisted of 14 long-term postoperative patients in median 30 month-time after DBS. UPDRS III scale was measured during 3 visits in 9 ± 2 months periods (V1, V2, V3) in total-OFF phase. Cognitive assessment was performed during each visit in total-ON phase. Results The comparable UPDRS III OFF gain was observed in both BMT-group and POP-group evaluations (p   0.05). Cognitive assessment revealed significant alterations between DBS-group and BMT-group in working memory, executive functions and learning abilities (p  Conclusions The impact of STN-DBS on UPDRS III OFF score and cognitive alterations suggest its neuromodulatory role, mainly during the first 9–18 months after surgery.