Biomarqueurs polysomnographiques des synucléinopathies dans le trouble du comportement en sommeil paradoxal, la maladie de Parkinson et l'atrophie multisystématisée

Isolated REM sleep behavior disorder (iRBD) is a key prodromal marker of alpha-synucleinopathies, such as Parkinson's disease (PD) and multisystem atrophy (MSA). This thesis focuses on the identification of novel polysomnographic biomarkers to better differentiate these disorders at an early stage. Our research revolves around two markers during sleep that could serve as early indicators of neurodegenerative processes, tested in a large cohort of patients with RBDi, PD, MSA and healthy subjects who all benefited from systematic videopolysomnography (PSG). Analyses were visual (sighs) and visual then automated by artificial intelligence (rapid eye movements).First, we focused on sighs during deep slow wave sleep (N3). Sighs were more frequent in MSA patients, than in PD and iRBD patients, or in healthy subjects. This suggests that increased sighing in N3 sleep could be a specific biomarker of MSA. The ability to differentiate MSA from other synucleinopathies is crucial, as MSA progresses more rapidly than PD. Simple integration of this measure into PSG assessments could therefore enable earlier diagnosis and intervention, improving the clinical outlook for MSA patients. In a second step, we examined the presence of rapid eye movements (REMs) during non-REM sleep (N2). REMs are usually restricted to REM sleep, but their appearance during N2 may suggest a disruption of normal sleep architecture. Using visual and automated coding, an abnormal REMs threshold in non-REM sleep distinguished patients with PD and MSA from control subjects, but not patients with iRBD. These results underline the potential of PSG as a non-invasive tool for the early detection of abnormalities associated with neurodegenerative diseases, beyond REM sleep without atonia. The identification of sighs in N3 and REMs in NREM N2 sleep offers a new approach to the diagnosis of synucleinopathies during the numerous polysomnograms performed for other reasons (especially sleep apnea) at this age, and sometimes at the prodromal stage.