Gender and onset age related-differences of non-motor symptoms and quality of life in drug-naive Parkinson's disease

Objective: This study aims to explore the gender and onset age-related differences of non-motor symptoms (NMS) and the determinants of quality of life (QoL) in a large cohort of Chinese drug-naive Parkinson's disease (PD) patients. Patients and methods: A cross-sectional analysis of 569 drug-naive PD patients was conducted. The frequency and severity of each NMS was evaluated by Non-Motor Symptom Scale (NMSS), which consists of 9 subdomains. PD Questionnaire-39 (PDQ-39) was used to assess the QoL of PD patients. A stepwise multiple regression model was used to explore the determinants of QoL. Results: A total of 552 patients (97.0%) exhibited at least one NMS. The three most common NMS were sleep/ fatigue (74%), attention/memory (62.7%) and miscellaneous (62%). The frequencies of sleep/fatigue and mood/apathy were more prevalent in women and the frequencies of urinary and sexual dysfunction were more prevalent in men (P < 0.05). Patients with late-onset PD showed higher frequencies of perceptual problems/ hallucinations, attention/memory, gastrointestinal, urinary, sexual dysfunction, and miscellaneous compared to patients with early-onset PD (P < 0.05). The multiple regression analysis model indicated that female, disease duration, UPDRS III score, depression, and NMSS subcores including sleep/fatigue, mood/apathy, attention/ memory, and gastrointestinal were the determinants of QoL in patients with drug-naive PD. Conclusions: NMS was common in untreated PD patients. They are heterogeneous in patients with drug-naive PD, which are dramatic determinants on decreased QoL in PD. Our results are beneficial for clinical management of NMS in drug-naive PD.