Validation of the nonmotor symptoms questionnaire for Parkinson's disease: results from a Chinese pilot study

We performed a cross-sectional study of 82 Chinese patients with Parkinson's disease (PD) enrolled during an 18-month period. We used a clinical interview to evaluate a Chinese version of the nonmotor symptoms questionnaire (NMSQuest) as an instrument for measuring the nonmotor symptoms (NMS) in Chinese patients with PD. The patients' cognitive deficit, depression/sleep, disease severity and motor status were assessed based on the mini-mental state examination (MMSE), the Hamilton depression scale (HAMD)/Parkinson's disease sleep scale (PDSS), the modified Hoehn and Yahr staging scale (H&Y) and the unified Parkinson's disease rating scale part III (UPDRS III), respectively. Thirty items distributed in nine different domains of the NMSQuest were evaluated, and the association between the NMSQuest and MMSE, H&Y, UPDRS, HAMD and PDSS was identified. Significant correlations were observed between the NMSQuest and disease duration (r(s) = 0.272, p = 0.013), UPDRS total score (r(s) = 0.444, p < 0.001), UPDRS II (r(s) = 0.415, p < 0.001) and UPDRS III (r(s) = 0.228, p = 0.039). Furthermore, the sleep disorder and mood (depression/anxiety) domain of the NMSQuest were significantly correlated with the PDSS (r(s) = -0.471, p < 0.001) and HAMD (r(s) = 0.687, p < 0.001), respectively. Our results indicate that the Chinese version of the NMSQuest, a useful screening tool, can be considered as a comprehensive, practical measure for NMS evaluation in Chinese PD patients. The NMSQuest highlights the prevalence of the wide range of NMS and indicated good responsiveness and interpretability. We strongly recommend routine use of the simplified Chinese version of NMSQuest in this country.