Circadian rhythm: from preclinical to post-diagnosis dementia

ongoing

Circadian rhythm (CR) regulates body functions over the 24-hour day/night period; sleep/wake cycle is its most visible manifestation. CR disruptions have long been observed in patients with dementia and emerging evidence points to their presence in the preclinical period of dementia. This suggests that certain aspects of CR could be useful in identification of high-risk individuals and could serve as potential targets for interventions to delay dementia onset and progression. This requires an in-depth understanding of the role of CR in dementia pathogenesis. As population ageing increases dementia burden, it is critical to find strategies to identify patients at risk of dementia with precision, prevent, and slow its progression. Building on recent advances in accelerometery (to assess CR features comprehensively) and dementia biomarkers (deep-phenotyping of dementia pathogenesis), RHYTHM IN DEMENTIA will make a decisive step-change in knowledge by determining CR features involved in dementia processes along the course of the disease. The aims are: 1) identify core CR features that shape 10-year risk of dementia in a community-dwelling cohort of 4000 older adults; 2) uncover specific CR disruptions that characterise major dementia subtypes and stages of Alzheimer’s disease (determined by biomarkers) in a new cohort of 1500 patients recruited from two memory clinics in Paris; and 3) ascertain how CR affects dementia prognosis in the patient cohort by examining cognitive and functional decline, hospitalisation, institutionalisation, and mortality. This project will yield new insight into the nature of the association between CR and dementia progression. These findings will ultimately inform the potential for a cost-effective and easy to use tool to assess CR features to facilitate both identification of patients at risk of dementia and tailored secondary prevention interventions that address CR disruptions in dementia patients and slow progression of dementia.