Investigation of the nonmotor symptoms in patients with STN-DBS therapy in comparison with those without STN-DBS.

The impact of STN-DBS on NMS remains rather as an underestimated topic. Besides, the significance of NMSs in QOL indexes of PD subjects with STN-DBS is unknown. We primarily aimed to evaluate the NMSs and their significance in QOL indexes in PD subjects comparatively with and without STN-DBS therapy. We enrolled all consecutive PD subjects with and without STN-DBS who applied to our movement disorders outpatient clinics between January/2023 and September/2023. We performed comprehensive assessments of the motor and nonmotor features including the clinical scales of Movement Disorder Society-sponsored revision of the MDS-UPDRS, NMSS, HAM-A, HAM-D, and the PDQ-39. Overall, 48 PD subjects with STN-DBS and 161 without STN-DBS treatment were included. The comparative analyses revealed that the sub-scores of the MDS-UPDRS-2, -3 and -4 were higher in the STN-DBS group. However, the MDS-UDPRS-1 and the total scores of the NMSS were similar between groups. Among eight subitems of the NMSS, only, the sub scores of the mood/cognition and the gastrointestinal tract differed. Remarkably, the significant correlations between the scores of the QOL and the NMSS scores in the STN-DBS (-) group, did not persist within the STN-DBS group. Remarkably, the correlations between the NMSS and PQQ-39 disappeared for most of the sub scores within the STN-DBS group. We found indirect evidence regarding the benefit of STN-DBS therapy on NMSs in our cross-sectional study. Besides, we found weaker impact of NMSs in QOL indexes in PD subjects with STN-DBS therapy.