The role of sleep disturbances in the emergence of neuropsychiatric symptoms in aging and neurodegenerative diseases – SENPSY

It is estimated that around 139 million individuals will suffer from dementia worldwide by 2050, with Alzheimer’s disease (AD) and dementia with Lewy Bodies (DLB) being the leading causes. No curative nor preventive treatment is yet available, although disease-modifying therapies for AD do offer some hope. Notably, we still need to better understand the early mechanisms and clinical consequences of neurodegenerative processes, to help developing effective prevention strategies. In this context, the role of sleep disturbances has gained attention, as they are increasingly recognized as a potential risk factor for dementia. Yet, we still do not fully understand the specific nature of sleep disturbances in AD versus DLB, their differential associations with underlying pathology and clinical consequences. Indeed, if the impact of sleep disturbances on memory deficits are well established, their associations with non-cognitive symptoms such as neuropsychiatric symptoms, is surprisingly very underexplored. Given the prominent role of sleep in emotions regulation, we believe that sleep problems and neuropsychiatric symptoms (especially psycho-affective disturbances such as anxiety and depression) may be intimately inter-related. The SENPSY project will finely 1) compare sleep disturbances between cognitively unimpaired older individuals, AD and DLB patients, 2) investigate the associations with underlying neurodegeneration, amyloid, tau and alpha-synuclein pathologies, and 3) determine their cross-sectional and longitudinal associations with the severity and emergence of neuropsychiatric symptoms, especially psycho-affective disturbances. SENPSY will bring comprehensive new insights on how early and specifically sleep disturbances relate to AD and DLB biomarkers and associated clinical symptoms, contributing to the recognition of sleep as a potential therapeutic target to reduce dementia risk and improve quality of life in older populations.