Cognitive impairment and dementia are a public health priority. Disturbed sleep has recently been identified as a risk factor for dementia. However, many of these studies occur in an older population. Dementia-related changes occur in the brain decades before the onset of disease, and longitudinal studies examining this relationship are costly and lengthy. To overcome these limitations, we will use genetic techniques to study the casual relationship between sleep and circadian disruption and dementia. We will analyze existing sleep and brain scan data from almost 95 000 individuals from 3 sources: Ontario Health Study, Memory and Aging Project, and UK Biobank. We will determine which genetic variants are associated with sleep fragmentation. Then we will relate these genetic variants to genetic variants associated with dementia to determine if there is a casual relationship between sleep deprivation and dementia-associated brain and cognitive changes. We predict that sleep fragmentation will be casually related to dementia. The project is expected to take 2 years to complete. Results from this study will inform clinical trials that target sleep or the discovery of new treatments which can potentially improve the health of millions of older adults that are at a higher risk of developing dementia.
