Alzheimer's Disease
Conditions
Keywords
Retina, ALzheimer's disease, neurodegenerative signs
Brief summary
A few studies suggest that patients suffering from neurodegenerative diseases (such a multiple sclerosis or Alzheimer's disease (AD)) show decreased thickness of the retinal nerve fiber layer (RNFL), indicating axonal degeneration. High-definition spectral domain optical coherence tomography (SD-OCT), performed without radiation in a few seconds per eye, offers a precise and standardized estimation of this parameter, which could constitute a biomarker for cerebral axonal degeneration. These RNFL deficits might even be the earliest sign of AD, prior to damage of the hippocampal region that impacts memory. Besides, some associations of AD with some degenerative diseases of the eye (glaucoma, microvascular abnormalities, age-related macular degeneration (AMD)) have also been reported. It therefore seems interesting to determine whether RNFL thickness, and other ocular parameters, may give some indications for a better detection of AD and cognitive decline in the elderly.
Interventions
OTHEROphthalmological examination & Questionnaire
The following examinations will be performed, after pupil dilation: * Examination with SD-OCT (macular scans, macular volume, peri-papillary scan, retinal autofluorescence, infer-red and red-free imaging) * Colour photographs of the retinal, centered on the macula and on the optic nerve (digital non mydriatic retinal camera) * Wide-field colour and autofluorescence imaging (Optomap) * Measure of intra-ocular pressure (pneumotonometer) The following informations will be collected through a standardized questionnaire, administered face-to-face during the inclusion visit, or at the moment of the verification of eligibility criteria: * Age, gender * educational level * smoking * cardiovascular diseases, current medications * scores at neuropsychological tests
Sponsors
University Hospital, Bordeaux
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
50 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Inclusion criteria for AD cases: * Diagnosis of probable AD, defined according to the NINCDS-ARDRA criteria51 * Light to moderate severity of the disease, defined by a MMSE score \>10 (global evaluation of cognition) * Patient aged 50 years or more * Patient benefiting from social insurance Inclusion criteria for controls: * Absence of suspicion of dementia, based on normal performance according to age and educational level at neuropsychological testing defined as: * Free recall ≥17 and total recall ≥40 for the Free and Cued Selective Reminding Test (Grober and Buschke test 52) MMSE ≥ norm for age and educational level (defined by mean - 1 SD) * Isaac's set test ≥ norm for age and educational level (defined by mean - 1 SD) * Matched to age and gender of the cases * Patient benefiting from social insurance
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| RNFL thickness measured on a peri-papillary scan of SD-OCT examination. | inclusion visit (day0) |
Secondary
| Measure | Time frame |
|---|---|
| Glaucomatous optic nerve damage observed on colour photographs (cup/disc ratio) | inclusion visit (day0) |
| Retinal microvascular abnormalities (microaneurysms, micro-hemorrhage, cotton wool spots, arteriovenous nicking), observed on retinal colour photography | inclusion visit (day0) |
| Macular abnormalities observed on retinal colour photographs (drusen, pigmentary abnormalities, neovascular AMD, atrophic AMD, other retinal diseases) | inclusion visit (day0) |
| Macular abnormalities observed on macular scans in SD-OCT (drusen, pigmentary abnormalities, neovascular AMD, atrophic AMD, epiretinal membranes, other retinal diseases). | inclusion visit (day0) |
| Macular abnormalities observed in autofluorescence imaging (increased autofluorescence, decreased autofluorescence, reticular drusen, atrophic AMD, other abnormalities) | inclusion visit (day0) |
| Macular and peripheral abnormalities diagnosed in wide-field retinal imaging | inclusion visit (day0) |
| Retinal blood flow velocity (RFI) | inclusion visit (day0) |
| Intraocular pressure | inclusion visit (day0) |
| axial length | inclusion visit (day 0) |
Countries
France
Contacts
PRINCIPAL_INVESTIGATORJean-François KOROBELNIK, Pr
University Hospital, Bordeaux, France
STUDY_CHAIRDelcourt Cécile, Dr
ISPED, bordeaux, France
Outcome results
None listed