Evaluation of Non-Motor Symptoms in Wilson Disease Using the Parkinson's Disease Nonmotor Symptoms Questionnaire: A Pilot Cross-Sectional Study and Critical Assessment

BACKGROUND: There is a dearth of studies on non-motor symptoms of Wilson's disease (WD) which is primarily because of the non-availability of a suitable scale. OBJECTIVE: To assess the suitability of the Parkinson's Disease non motor symptoms questionnaire (PD-NMS Quest) in the assessment of non-motor symptoms of WD patients. METHODS: In this case-control study, patients of WD above ≥12 years of age diagnosed by Leipzig's criteria and age and gender-matched control subjects were recruited. Critically ill patients, patients with severe hepatic impairment, or with pure hepatic WD were excluded. PD-NMS Quest was applied and relevant statistical analyses were performed. RESULTS: A total of 18 cases and 25 controls were studied. Patients had a mean age of 22.6 years and a median disease duration of 8 years. WD patients had higher frequencies of all NMS than controls. Drooling (P = 0.0037), dysphagia or choking (P = 0.0088), nocturia (P = 0.0471), anxiety/fear (P = 0.0337), feeling sad or blue (P = 0.0020) and falling (P = 0.0197) were significantly higher in WD patients than controls. CONCLUSIONS: Although many NMS of WD patients are picked up effectively with PD-NMS Quest, some of them need detail assessment including cognitive, behavioral, and psychiatric symptoms, drooling and dysphagia, sleep as well as autonomic disturbances. Questions pertaining to sexual activity may be omitted from the questionnaire.