Fine-mapping the contribution of sleep alterations to neurodegeneration – a prospective polysomnographic study in the general population

• Applicant: Professor Dr. Hans Jörgen Grabe
• Subject Area: Biological Psychiatry
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 406711066

Dementias are neurodegenerative disorders caused by a complex interaction between modifiable and non-modifiable factors. Among these, sleep has been recently gaining attention, with a study estimating that up to 15% of Alzheimer cases could be delayed or prevented through the effective treatment of sleep disorders. In the initial project, we found strong associations between obstructive sleep apnoea and advanced brain ageing and white matter hyperintensity burden, as well as between slow-wave sleep and Alzheimer-related brain atrophy patterns. But while these results are compatible with hypothesized pathophysiological pathways, some controversy remains regarding other published results. This might indicate that the categorization and/or temporal compression of the used metrics of sleep macro-architecture and obstructive sleep apnoea might not accurately reflect the relevant sleep processes. Using cross-sectional and longitudinal polysomnography and structural MRI data from the Study of Health in Pomerania (SHIP-Trend-0/1) general population study, we therefore propose to extend our analyses to EEG-based microstructural events, global sleep markers incorporating temporal and individual-specific dynamics of sleep and hypoxic markers assessing the temporal and structural composition of these events. We believe that these markers will clarify some of the controversy and provide additional insight into the impact of sleep and obstructive sleep apnoea on dementia-related neurodegeneration.

• DFG Programme: Research Grants