Parkinson’s Disease-Related pattern in isolated REM sleep behaviour disorder as a prodromal progression marker: 8-Year Follow-Up changes assessed at three time points

• Published in: European journal of nuclear medicine and molecular imaging Vol. 52; no. 10; pp. 3550 - 3556
• Main Authors: Carli, Giulia, Dortmond, Anna, Janzen, Annette, Sittig, Elisabeth, De Meyer, Eline, Leenders, Klaus L., Oertel, Wolfgang, Meles, Sanne
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2025; Springer Nature B.V
• Subjects: Age; Aged; Basal ganglia; Biomarkers; Cardiology; Central nervous system diseases; Dementia disorders; Disease Progression; Female; Fluorodeoxyglucose F18; Follow-Up Studies; Humans; Identification; Imaging; Lewy bodies; Longitudinal studies; Male; Medical imaging; Medicine; Medicine & Public Health; Middle Aged; Movement disorders; Neurodegenerative diseases; Neuroimaging; Nuclear Medicine; Oncology; Orthopedics; Parkinson Disease - complications; Parkinson Disease - diagnostic imaging; Parkinson's disease; Positron emission; Positron emission tomography; Prodromal Symptoms; Radiology; REM sleep; REM Sleep Behavior Disorder - complications; REM Sleep Behavior Disorder - diagnostic imaging; Short Communication; Sleep disorders; Standard scores; Time Factors; Variance analysis; Canada; Montreal Quebec Canada; F-FDG PET; brain glucose metabolism; iRBD; disease progression; PDRP; 18F-FDG PET
• ISSN: 1619-7070; 1619-7089; 1619-7089
• DOI: 10.1007/s00259-025-07260-9

Background Isolated REM sleep behavior disorder (iRBD) is a prodromal stage of alpha-synucleinopathies. Biomarkers are crucial for predicting and monitoring its progression, warranting long-term neuroimaging studies. While the Parkinson's Disease Related Pattern (PDRP) from 18 F-FDG PET is a recognized Parkinson's Disease (PD) biomarker, its role in tracking progression in prodromal PD remains unclear. Objective To explore PDRP expression across three time points using 18 F-FDG PET over an 8-year follow-up in iRBD. Methods Thirteen iRBD subjects underwent 18 F-FDG PET brain scans at baseline (BL), follow-up 1 (FU1, 4 years), and follow-up 2 (FU2, 8 years). Among them, four developed PD, one Dementia with Lewy Bodies (DLB), three showed subthreshold parkinsonism, and five showed no progression. PDRP z-scores were analyzed within and between groups (converters vs. non-converters) using a two-way repeated measures ANOVA. Similar analyses were conducted for motor scores (Unified Parkinson’s Disease Rating Scale part three, UPDRS-III). Results There was a significant main effect of group ( p  = 0.011), time ( p  < 0.001), and a group*time interaction ( p  = 0.020), indicating that while PDRP z-scores increased over time in most iRBD subjects, the increase was more pronounced in converters ( n  = 5) than in non-converters ( n  = 8). Post-hoc tests revealed significantly higher PDRP z-scores in converters compared to non-converters at FU1 ( p  = 0.042) and FU2 ( p  = 0.024). For UPDRS-III scores we found significant effects of group ( p  = 0.011), time ( p  < 0.001), and their interaction ( p  = 0.0003). Conclusions Repeated 18 F-FDG PET scans may be useful to monitor prodromal disease progression and predict conversion in iRBD patients.