Protocol for a scoping review of measurement of sleep in mild cognitive impairment and early dementia

Sleep abnormalities are increasingly recognised to emerge early in dementia, at or before the Mild Cognitive Impairment (MCI) phase. Abnormal sleep accelerates cognitive decline and may directly contribute to pathophysiology. Its accurate measurement is therefore crucial, firstly to characterise sleep abnormalities in early disease potentially facilitating earlier identification of those at risk of dementia and secondly to test sleep intervention efficacy. However, it is our a priori hypothesis that sleep outcomes are reported heterogeneously inhibiting side-by-side comparison of study findings. As a translational step towards informing choice and decisions on optimal measures, this scoping review will describe measurement tools utilised and sleep parameters currently reported in early dementia and MCI. This scoping review follows the Joanna Briggs Institute Manual for Evidence Synthesis for Scoping Reviews. The search strategy consists of an electronic search of the CINAHL Plus, Embase, Medline, Psychinfo and British Nursing Index databases and date limited to articles published from 2000. Search results will be merged using reference management software and duplicates removed. 10% of returned titles and abstracts will be checked by each reviewing member to ensure continuity of decision making. Full-texts will be reviewed by at least two reviewers with discrepancies resolved by whole team consensus. A PRISMA flow diagram will document the selection process. Extracted data will be analysed and reported narratively. This scoping review will identify which sleep parameters are reported and the means by which they are measured in people with MCI or early dementia. We intend to explore differences in reporting practice within group subsets, e.g. by dementia and study subtype. Ethical approval is not required due to absence of human participants. Results will be published in a peer-reviewed journal and presented at relevant academic conferences. The search strategy will be made available publicly for transparency.