Objective: To investigate the brain bioelectric activity during REM/NREM sleep and determine the relationship with visual impairment and structural brain alteration in non-demented PD patients with RBD.

Background: Pathological cortical activation during REM/NREM sleep underlies sleep disorders and may favor Parkinson’s disease (PD) progression. Factors such as PD-related visual impairment, may also contribute to the manifestation of REM Behavioral Disorder (RBD). We assume that RBD should have association with the specific structural changes of the brain.

Method: 28 PDpatients aged 45-56 years were divided into 2 groups according to the presence (group 1) and absence of RBD (group 2), and 20 age-match healthy were included in the control group.
      Polysomnography with quantitative EEG spectral power analysis was used for sleep assessment. Visual function was evaluated by threshold perymetry and  measurement of contrast sensitivity (CS). Structural brain alteration was investigated by MRI voxel-based morphometry (VBM).

Results: There were no differences between groups in terms of age, duration and PD severity. All PD patients showed a significant decrease in retinal sensitivity thresholds and CS as compere with control. During NREM sleep, slow-wave activity (SWA) reduction was observed in all regions in 1st and 2nd group. However, RBD patients displayed a more pronounced decline in SWA over frontal regions during NREM and an increase in α and β band power over the parietal-occipital regions during REM sleep. In both groups of PD patients, VBM demonstrated a bilateral grey matter (GM) reduction in the prefrontal cortex and in structures of the dorsal and ventral visual streams. Wherein, PD patients with RBD had a significant increase in the amygdala GM as well as PAG density. We found the association between reduced NREM sleep SWA over frontal regions and prefrontal cortex GM. In addition, GM reduction in the inferior occipital gyrus, lingual cortex, middle temporal gyrus, posterior cingulate had positive correlation with deterioration in CS.

Conclusion: RBD in PD is based on selective structural changes in the brain that lead to topographically related disturbances of the bioelectrical activity during REM/NREM sleep. PD-related visual impairment may contribute in primary and secondary visual cortex reduction which also facilitates RBD development

« Back to 2022 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/relationship-between-brain-bioelectrical-activity-during-rem-nrem-sleep-grey-matter-changes-and-visual-disorders-in-patients-with-rbd-in-parkinsons-disease/