The heterogeneity of non-motor symptoms of Parkinson's disease

In addition to motor symptoms, patients with Parkinson's disease (PD) may experience non-motor symptoms (NMS), more often with more advanced disease stage. However, the clinical feature of the NMS and potential risk factors that affect NMS in idiopathic PD patients remain unclear. 493 PD patients diagnosed with PD via the UK. Parkinson's Disease Society Brain Bank Clinical Diagnostic Criteria and 93 healthy control subjects (CN) were recruited in the current study. Questionnaires were used to assess the NMS, motor symptoms, cognitive function, and disease severity in both groups. Levodopa daily dose was calculated in PD patients. Multivariate linear regression analysis was used to identify the risk factors that potentially affect NMS in PD patients. The results showed that, the NMS occurrence and positive endorsement rate of PD patients were significantly higher compared to CN subjects. Multiple stepwise regression analysis found the motor symptom was the only factor that affected NMS in PD patients within five years of the disease course, whereas motor symptoms, cognitive function, disease severity and Levodopa daily dose significantly affected NMS if the disease course was more than five years. These findings demonstrated that NMS are affected by several risk factors at different stages of PD. The distribution of difference NMS is associated with the severity of motor symptoms and the dosage of anti-PD medications in Chinese PD patients.