LESCOD: Lewy Body Screening in Cognitive Disorders

Study Overview
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Brief Summary
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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

Official Title
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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

Conditions
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Lewy Body Disease, Alzheimer Disease

Intervention / Treatment
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* Other: LeSCoD scale


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be a woman or a male >60 to < 90 years Have sufficient visual and auditory acuity Be able to speak, read, hear and understand french language Be covered by health care insurance Have a reliable help/partner/informant/caregiver Have a mild to severe cognitive decline based on MMSE (Mini-Mental State Examination) score ( From 18 to 26) Give oral agreement to the assessment of the LEsCoD scale during routine consultation Have performed neuropsychology tests and MRI respectively within 6 and 12 months Exclusion Criteria: Has evidence of neurological or psychiatric disorder other than AD or DLB explaining cognitive decline Has received previously or currently neuroleptic treatment Has no reliable help/caregiver the day of the visit Refuses to give his/her oral agreement to the assessment of the LeSCoD scale Has presence on MRI of radiologic evidence of cerebrovascular disease (score Fazekas 2)

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Alzheimer disease (AD)<br>Patients with AD according to NINCDS-ADRDA (National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association) criteria Intervention: LeSCoD scale | Other: LeSCoD scale<br>* LeSCoD is a clinical scale<br>|
| Other: Dementia with Lewy Bodies (DLB)<br>Patients with probable DLB according to McKeith criteria. Intervention: LeSCoD scale | Other: LeSCoD scale<br>* LeSCoD is a clinical scale<br>|
| Other: Probable AD and possible DLB<br>Patients with clinical criteria for possible or probable AD and possible DLB Intervention: LeSCoD scale | Other: LeSCoD scale<br>* LeSCoD is a clinical scale<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Construct validity of the LeSCoD scale with a factorial analysis | The study consists in one single mandatory visit and 2 optional visits. The clinical scale is performed during the inclusion visit which corresponds to a routine consultation scheduled at the memory clinic | Day 0 (during the inclusion visit) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic validity of the Lescod scale by measuring the sensitivity and the specificity | The study consists in one single mandatory visit and 2 optional visits. The clinical scale is performed during the inclusion visit which corresponds to a routine consultation scheduled at the memory clinic | Day 0 (During the inclusion visit) | 
| Intergroup variance will be used to assess the quality of the patient denomination | The study consists in one single mandatory visit and 2 optional visits. The clinical scale is performed during the inclusion visit which corresponds to a routine consultation scheduled at the memory clinic | Day 0 (during the inclusion visit) | 
| Concurrent validity will be assessed by the measurement of the striatal dopaminergic depletion and its correlation with the Lescod score | The study consists in one single mandatory visit and 2 optional visits. The clinical scale is performed during the inclusion visit which corresponds to a routine consultation scheduled at the memory clinic | Day 0 (during the inclusion visit) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Alzheimer Disease, Lewy Body Disease