Static and dynamic brain morphological changes in isolated REM sleep behavior disorder compared to normal aging

Gilsoon Park; Hyunjin Jo; Yaqiong Chai; Hea Ree Park; Hanul Lee; Eun Yeon Joo; Hosung Kim

doi:10.3389/fnins.2024.1365307

Static and dynamic brain morphological changes in isolated REM sleep behavior disorder compared to normal aging

Front Neurosci. 2024 May 1:18:1365307. doi: 10.3389/fnins.2024.1365307. eCollection 2024.

Authors

Gilsoon Park^#¹, Hyunjin Jo^#^{2

3}, Yaqiong Chai¹, Hea Ree Park⁴, Hanul Lee², Eun Yeon Joo², Hosung Kim¹

Affiliations

¹ USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States.
² Department of Neurology, Neuroscience Center, Samsung Medical Center, Samsung Biomedical Research Institute, School of Medicine, Sungkyunkwan University, Seoul, Republic of Korea.
³ Medical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea.
⁴ Department of Neurology, Inje University College of Medicine, Ilsan Paik Hospital, Goyang, Republic of Korea.

^# Contributed equally.

Abstract

Objective/background: To assess whether cerebral structural alterations in isolated rapid eye movement sleep behavior disorder (iRBD) are progressive and differ from those of normal aging and whether they are related to clinical symptoms.

Patients/methods: In a longitudinal study of 18 patients with iRBD (age, 66.1 ± 5.7 years; 13 males; follow-up, 1.6 ± 0.6 years) and 24 age-matched healthy controls (age, 67.0 ± 4.9 years; 12 males; follow-up, 2.0 ± 0.9 years), all participants underwent multiple extensive clinical examinations, neuropsychological tests, and magnetic resonance imaging at baseline and follow-up. Surface-based cortical reconstruction and automated subcortical structural segmentation were performed on T1-weighted images. We used mixed-effects models to examine the differences between the groups and the differences in anatomical changes over time.

Results: None of the patients with iRBD demonstrated phenoconversion during the follow-up. Patients with iRBD had thinner cortices in the frontal, occipital, and temporal regions, and more caudate atrophy, compared to that in controls. In similar regions, group-by-age interaction analysis revealed that patients with iRBD demonstrated significantly slower decreases in cortical thickness and caudate volume with aging than that observed in controls. Patients with iRBD had lower scores on the Korean version of the Mini-Mental Status Examination (p = 0.037) and frontal and executive functions (p = 0.049) at baseline than those in controls; however, no significant group-by-age interaction was identified.

Conclusion: Patients with iRBD show brain atrophy in the regions that are overlapped with the areas that have been documented to be affected in early stages of Parkinson's disease. Such atrophy in iRBD may not be progressive but may be slower than that in normal aging. Cognitive impairment in iRBD is not progressive.

Keywords: MRI analysis; cerebral cortical thinning; longitudinal studies; rapid eye movement sleep behavior disorder; subcortical volume atrophy.

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. This work was supported in part by the National Institute of Health [Grant numbers: P41EB015922, 1R01AG066711]; Samsung Medical Center Grant [Grant number: OTC1190671]; and a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea [Grant number: HI19C1328].