LESCOD: "A Single Center, Prospective Study Aimed at Validating a Clinical Scale, Screening for Symptoms of Lewy Body Disease in Patients Incipient Dementia of the Alzheimer's and/or Lewy Body Type"

Dementia with Lewy body (DLB) is the second most common neurodegenerative dementia in autopsy series. However, DLB represents a small proportion of the clinical diagnoses in epidemiology registries. Indeed Alzheimer disease (AD) and DLB are often concomitant, they share many symptoms and only a small weight is given to non-motor symptoms in DLB diagnosis. DLB is at the end of a pathological spectrum overlapping with AD, explaining the poor diagnostic value of both diagnostic criteria. To date there is still a need for a tool able to discriminate patients with pure DLB from those expressing common signs with both AD and DLB and those with pure AD. The purpose of this study is to validate a semi quantitative scale designed to reflect the Lewy Bodies burden in patients with mild to moderate cognitive decline. The investigators hypothesized that the score obtained may differentiate between AD, DLB and patients fulfilling clinical criteria for both DLB an AD. This score could also be correlated with dopaminergic depletion assessed with [18F]fluorodopa PET/computed tomography and/or with potential biomarkers of ADD measured in cerebrospinal fluid. This clinical validation is a preliminary work preceding further studies correlating the LeSCoD score with functional imaging features, prognosis and therapeutic response. Thus, the expected outcomes involve an improvement in demented patients' care, as well as a better patient selection for further therapeutic studies