Sex, myelin, and clinical characteristics of Parkinson's disease

Jiayue Cai; Jowon L Kim; Yuheng Wang; Tobias R Baumeister; Maria Zhu; Aiping Liu; Soojin Lee; Martin J McKeown

doi:10.3389/fnins.2023.1235524

Sex, myelin, and clinical characteristics of Parkinson's disease

Front Neurosci. 2023 Sep 13:17:1235524. doi: 10.3389/fnins.2023.1235524. eCollection 2023.

Authors

Jiayue Cai^{1

2}, Jowon L Kim², Yuheng Wang³, Tobias R Baumeister³, Maria Zhu², Aiping Liu⁴, Soojin Lee², Martin J McKeown²

Affiliations

¹ School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen University, Shenzhen, Guangdong, China.
² Department of Medicine, The University of British Columbia, Vancouver, BC, Canada.
³ School of Biomedical Engineering, The University of British Columbia, Vancouver, BC, Canada.
⁴ Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China.

Abstract

Objective: To determine if there are sex differences in myelin in Parkinson's disease, and whether these explain some of the previously-described sex differences in clinical presentation.

Methods: Thirty-three subjects (23 males, 10 females) with Parkinson's disease underwent myelin water fraction (MWF) imaging, an MRI scanning technique of in vivo myelin content. MWF of 20 white matter regions of interest (ROIs) were assessed. Motor symptoms were assessed using the Unified Parkinson's Disease Rating Scale (UPDRS). Principal component analysis, logistic and multiple linear regressions, and t-tests were used to determine which white matter ROIs differed between sexes, the clinical features associated with these myelin changes, and if overall MWF and MWF laterality differed between males and females.

Results: Consistent with prior reports, tremor and bradykinesia were more likely seen in females, whereas rigidity and axial symptoms were more likely seen in males in our cohort. MWF of the thalamic radiation, cingulum, cingulum hippocampus, inferior fronto-occipital fasciculi, inferior longitudinal fasciculi, and uncinate were significant in predicting sex. Overall MWF and asymmetry of MWF was greater in males. MWF differences between sexes were associated with tremor symptomatology and asymmetry of motor performance.

Conclusion: Sex differences in myelin are associated with tremor and asymmetry of motor presentation. While preliminary, our results suggest that further investigation of the role of biological sex in myelin pathology and clinical presentation in Parkinson's disease is warranted.

Keywords: Parkinson’s disease; clinical characteristics; myelin water fraction; sex; white matter microstructure.