Sleep, Cognition and Memory Disorder

The increasing incidence of Alzheimer's disease (AD) and related sleep-disorders with the aging of the population is a major issue of public health. The prevalence of sleep disturbances is about 50% in dementia patients. Sleep in dementia is mainly characterized by prolonged night-time awakenings, sometimes with longer sleep latency and/or early awakening. The presence of these sleep disturbances is the main reason for the institutionalization of AD patients, as well as a major cause of the deterioration of the caregivers' sleep. The MEMENTO cohort is composed of patients with isolated memory complaints or mild cognitive impairment, at high risk to develop dementia. All voluntary patients from the CMRR (Center of Memory, resources and Research) of Bordeaux (MEMENTO cohort) will be tested at inclusion and followed-up 1 year later. For these two evaluations, actigraphic monitoring at home, 2-night polysomnography (PSG) monitoring at hospital including a 24-hour period of urinary melatonin dosage, neuropsychological tests battery, a virtual reality tool and questionnaires will be used.