Subjects at risk of Parkinson’s disease in health checkup examinees: cross-sectional analysis of baseline data of the NaT-PROBE study

Introduction The present study aimed to survey the prevalence of prodromal symptoms of Parkinson’s disease (PD) in Japanese health checkup examinees, for identifying at-risk subjects. Methods We conducted a questionnaire survey of annual health checkup examinees without neurological symptoms using the following self-reported questionnaires: Japanese version of the Scale for Outcomes in Parkinson’s disease for Autonomic Symptoms (SCOPA-AUT); Self-administered Odor Question (SAOQ); REM Sleep Behavior Disorder Screening Scale (RBDSQ); Beck Depression Inventory-Second Edition (BDI-II); Epworth Sleepiness Scale (ESS); and Physical Activity Scale for the Elderly (PASE). The presence of prodromal symptoms was determined using the 90th percentile threshold of each questionnaire. Subjects ≥ 50 years of age with ≥ 2 core prodromal symptoms (dysautonomia, hyposmia, and RBD), were classified as at risk. Results Between March 2017 and March 2018, 4,953 participants sufficiently answered the questionnaires. Among 2,726 subjects ≥ 50 years of age, 155 were classified as at risk. These subjects had worse values of BDI-II (12.0 ± 8.3 vs. 4.4 ± 3.8, p