Diffusion tensor metrics, motor and non-motor symptoms in de novo Parkinson's disease

Author(s)

Soares, Nayron Medeiros ; da Silva, Pedro Henrique Rodrigues ; Pereira, Gabriela Magalhaes ; Leoni, Renata Ferranti ; Rieder, Carlos Roberto de Mello ; Alva, Thatiane Alves Pianoschi

• Document type: Journal article
• Source: NEURORADIOLOGY; v. 66, n. 11, p. 12-pg., 2024-08-27.

Abstract

Introduction Parkinson's disease (PD) is a neurodegenerative disorder characterized by dopaminergic neurons' degeneration of the substantia nigra, presenting with motor and non-motor symptoms. We hypothesized that altered diffusion metrics are associated with clinical symptoms in de novo PD patients. Methods Fractional Anisotropy (FA) and Mean (MD), Axial (AD), and Radial Diffusivity (RD) were assessed in 55 de novo PD patients (58.62 +/- 9.85 years, 37 men) and 55 age-matched healthy controls (59.92 +/- 11.25 years, 34 men). Diffusion-weighted images and clinical variables were collected from the Parkinson's Progression Markers Initiative study. Tract-based spatial statistics were used to identify white matter (WM) changes, and fiber tracts were localized using the JHU-WM tractography atlas. Motor and non-motor symptoms were evaluated in patients. Results We observed higher FA values and lower RD values in patients than controls in various fiber tracts (p-TFCE < 0.05). No significant MD or AD difference was observed between groups. Diffusion metrics of several regions significantly correlated with non-motor (state and trait anxiety and daytime sleepiness) and axial motor symptoms in the de novo PD group. No correlations were observed between diffusion metrics and other clinical symptoms evaluated. Conclusion Our findings suggest microstructural changes in de novo PD fiber tracts; however, limited associations with clinical symptoms reveal the complexity of PD pathology. They may contribute to understanding the neurobiological changes underlying PD and have implications for developing targeted interventions. However, further longitudinal research with larger cohorts and consideration of confounding factors are necessary to elucidate the underlying mechanisms of these diffusion alterations in de novo PD. (AU)

• FAPESP's process: 22/03266-0 - Investigation of neuroimaging assessments and current flow modeling as target engagement and predictor biomarkers of convulsive therapies
• Grantee: Pedro Henrique Rodrigues da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral