Non-motor fluctuation patterns in dyskinetic patients with advanced Parkinson's disease

To explore the pattern of non-motor symptoms (NMS) and their fluctuations in dyskinetic patients with advanced Parkinson's disease (PD). Exploratory post-hoc analyses of the multicenter NoMoFlu-PD cross-sectional study originally designed to study NMS fluctuations using clinical examination of key NMS quantified using a visual analogue scale (VAS; assessing 10 key NMS: dysphagia/choking, anxiety/panic, depressive symptoms, fatigue, excessive sweating, inner restlessness, pain, concentration/attention, dizziness and bladder urgency) and the NMS scale (NMSS) in motor defined-On (NMS_On) and Off state (NMS_Off). Motor state independent assessments were performed using the Wearing-Off Questionnaire 9 (WOQ-9). Participants were either allocated to the dyskinesia group based on detailed medical history, clinical examination, and/or by Unified PD Rating Scale (UPDRS) part IV assessment (dyskinesia questions 32/33 sum score ≥ 1 point) or to the group of participants without any evidence of dyskinesia. Of 100 patients with PD (median [IQR] age: 69 [63-74] year, 54% males), 55% presented with dyskinesia. Frequency and severity patterns of NMS and their fluctuations were not different in dyskinetic compared to non-dyskinetic participants. This result was independent of the NMS assessment tool. NMS burden defined as the overall severities of NMS_on, NMS_Off and ΔNMS_On/Off did neither correlate with the presence of dyskinesia nor with dyskinesia severity as assessed by UPDRS-IV dyskinesia subscore or UPDRS-IV questions 32/33 sum score. Our findings suggest that NMS patterns and their fluctuations do not differ by dyskinesia status, and that NMS burden shows no link to dyskinesia severity. Future studies are warranted to confirm these results in larger cohorts.