Biomarkers of Sleep-wake Cycle in Prodromal Alzheimer's Disease: Role in Cognitive Decline?

Alzheimer's disease (AD) is characterised by a progressive loss of memory and cognitive function. In the early stages of AD, there is a progressive accumulation of molecules: β-amyloid peptides (Aβ) in the brain. There is a link between the accumulation of Aβ peptides and the deterioration of sleep, but current knowledge does not confirmed this link. The objective of this study is to define whether there is a link between cognitive decline and sleep disorders. If a correlation is found, this could allow earlier treatment of sleep disorders in the longer term in order to slow the development of AD.

Inclusion Criteria:Diagnosis of mild Alzheimer's disease with a Mini Mental State (MMS) between 21-30The presence of a family carer to complete neuropsychological scales, questionnaires and sleep diariesHaving a neurological assessment and/or follow-up requiring blood and cerebrospinal fluid (CSF) sampling with biomarkers for diagnostic purposesPatient who had a lumbar puncture less than one year ago or patient with a scheduled lumbar puncture as part of careSigned informed consentAble to carry out all visits and follow study proceduresAffiliation to the French social security systemExclusion Criteria:Genetic form of alzheimer's diseaseInsufficient clinical and paraclinical information for the diagnosis of ADAnticholinesterase and/or memantine treatment or on stable doses for at least 3 monthsUse of antidepressants, anxiolytics, hypnotics, neuroleptics, 15 days before inclusionPatient living in a nursing homeIlliteracy or inability to perform psycho-behavioural testsMajor physical or neurosensory problems that may interfere with the testsInitial contraindication to diagnostic lumbar puncture (LP) (spinal surgery, skin infection, haemostasis abnormality, intracranial hypertension, severe coagulation disorders, curative anticoagulant therapy, severe liver failure)Refusal to perform a diagnostic lumbar punctureContraindication to the use of E-Celsius: people weighing less than 40 kg, with intestinal disorders, with known swallowing disordersPatient deprived of liberty, by judicial or administrative decision;Major protected by law;Patient in a period of relative exclusion from another protocol or for whom the maximum annual compensation of €4500 has been reached;Refusal to participate in the protocol.