Nonmotor symptoms of 820 Taiwanese patients with Parkinson's disease: an exploratory-comparative study

Introduction Nonmotor symptoms (NMSs) severely affect the daily quality of life of patients with Parkinson's disease (PD). Although many studies have documented the clinical characteristics of NMSs in PD patients, some issues remain unaddressed. The severity and gender distribution of NMSs in Asian and the Western patients differ. The correlations between clinical characteristics and NMS manifestations remain unclear. We studied these relationships in a large cohort of Taiwanese PD patients. Methods Patients with PD were recruited from the outpatient clinic of a tertiary medical center and evaluated with standardized assessment protocols, including the NonMotor Symptoms Scale (NMSS), Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn and Yahr (H&Y) scale, Mini-Mental Status Examination, and Montreal Cognitive Assessment. Results Among 820 patients enrolled, 41.8% were female. The prevalence of the NMSs was 96.5%, with attention/memory (79.51%) being the most frequently involved domain. The mean severity score on the NMSS was 36.48 +/- 34.30. Male patients reported higher NMS prevalence and severity than female patients, mostly in the gastrointestinal tract and urinary domains. We found that the severity of NMSs was correlated with disease duration, UPDRS Part III score, and H&Y stage. Conclusion Although they exhibited similar NMS prevalence, Taiwanese PD patients reported less intense NMSs compared with those reported by Western patients. Furthermore, the NMS items our patients emphasized and gender discrepancies were distinct from those in Western studies.