Prevalence of sleep disturbances in people with mild cognitive impairment: a systematic review protocol

Objective: This review will determine the prevalence of sleep disturbances in individuals with mild cognitive impairment.

Introduction: Mild cognitive impairment is regarded as a transitional state between normal functioning and dementia, and has a high likelihood of conversion to dementia. Individuals with mild cognitive impairment may suffer more severe sleep disturbances compared with normal older people. In some studies, sleep disturbances were associated with significantly higher odds of mild cognitive impairment. There is a need for prevalence estimates of sleep disturbances in people with mild cognitive impairment based on the currently available literature to guide clinical health care professionals and public health policies.

Inclusion criteria: The review will consider studies reporting on the prevalence of sleep disturbances in individuals with mild cognitive impairment, using validated instruments, including subjective and/or objective measures. Studies will be excluded if the participants report sleep-related breathing or movement disorders. Studies using only the Mini-Mental State Examination to diagnose mild cognitive impairment will also be excluded.

Methods: The review will follow the JBI methodology for systematic reviews of prevalence and incidence. The MEDLINE (Ovid), Embase, Cochrane Library (CDSR and CENTRAL), CINAHL (EBSCOhost), PsycINFO (EBSCOhost), Scopus, and Web of Science Core Collection databases will be systematically searched from inception to the present with no language limitations. Analytical observational studies, including prospective and retrospective cohort, case-control, and cross-sectional studies, will be considered. Two reviewers will independently conduct the study selection, critical appraisal, and data extraction. Methodological quality will be evaluated using the JBI critical appraisal checklist for studies reporting prevalence data. A meta-analysis will be conducted to synthesize the prevalence data, where possible.

Review registration: PROSPERO CRD42022366108.