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BEAM: Brain-Eye Amyloid Memory Study

Recruiting
Conditions
Mild Cognitive Impairment
Vascular Cognitive Impairment
Alzheimer's Disease
Parkinson's Disease
Lewy Body Disease
Interventions
Other: Pittsburgh Compound B [11C]-PIB
Registration Number
NCT02524405
Lead Sponsor
Sunnybrook Health Sciences Centre
Brief Summary

The main objectives for this study are:

1. To investigate novel, non-invasive ocular measurements including optical coherence tomography and eye tracking in a cross-sectional study of participants with various neurodegenerative dementias against standard cognitive assessments and brain imaging measures; and

2. To assess the potential utility of ocular assessments for early detection in the pre-dementia, i.e. the so-called Mild Cognitive Impairment (MCI) stage, across the common neurodegenerative dementia syndromes and, Vascular Cognitive Impairment (VCI) due to small vessel disease (SVD).

3. To determine the prevalence and relevance of amyloid uptake on PET scanning across the dementias most commonly associated with amyloidosis. Specifically we aim to examine correlations with amyloid uptake status in patients symptomatic from the most common proteinopathies (ie amyloid, tau, synuclein) combined in varying degrees with the most common vasculopathies (ie small vessel disease) using multimodal structural and functional imaging, cognitive behavioral, and gait and balance measures, taking into account genetic risk markers (particularly apolipoprotein E genotypes) and fluid biomarkers ( eg cytokines, oxidative stress, lipidomics).

Detailed Description

1. Retinal correlations with neurodegeneration:

1. Retinal nerve fiber layer (RNFL) pattern will differ in participants in the MCI and early stages of LBD spectrum, AD, and VCI, relative to normal elders. i) RNFL thinning around the optic disc and macular thinning will correlate with hippocampal atrophy and with the cortical thickness signature of MCI and AD2-4. ii) If detected in the other disorders, RNFL thinning will also correlate with this topographical AD pattern of atrophy in those who are amyloid positive on PET. iii) Retinal and cortical thinning will predict brain amyloid PET. iv) Selective peripapillary RNFL thinning in the superior and inferior quadrants described in MCI/milder AD cases will correlate with precuneus and lingual gyrus cortical thinning respectively.

2. Retinal artery narrowing will correlate with presence of covert lacunar infarcts and retinal venular widening with moderate to severe periventricular white matter hyperintensities.

2. Amyloid deposition above accepted cut-offs will vary across the 4 cohorts and when present will correlate meaningfully with cognitive and behavioural patterns, including ocular (retinal and eye tracking), gait and balance measures and brain imaging results.

Specific hypotheses are:

1. Apoelipoprotein E e4 carrier status will increase likelihood of amyloid positivity across the cohorts.

2. Amyloid positivity will be associated with poorer short term memory performance, smaller hippocampal volumes, greater cortical thinning in signature areas traditionally associated with Alzheimer's disease, and also with lobar microbleed counts.

3. Small Vessel Disease burden as quantified on PD/T2 and FLAIR MRI will be associated with speed of processing, attention and executive functions and with a different pattern of cortical thinning involving more inferior and medial frontal regions.

4. Amyloid deposition as measured by regional standardized uptake value ratio (SUVR), and Small Vessel Disease burden will correlate differentially with structural imaging measures, as well as both functional and structural brain connectivity measures.

Study Procedures Overview The study procedures are listed below in the recommended order of assessment but may be performed in any sequence (with specific exceptions as described). Multiple assessments may be performed on the same day for participant convenience. Brain imaging and neuropsychology procedures should be completed within 4 months of screening.

Screening Visit Consent. The study will be explained and written informed consent for participation will be obtained from the patient or his/her substitute decision maker and the participant's study partner (if applicable).

Screening. The general and disease-specific inclusion and exclusion criteria will be assessed. If the MMSE, MoCA, DOC (Depression, Obstructive Sleep Apnea, Cognition) questionnaire and/or TorCA (formally known as Behavioural Neurology Assessment - Revised (BNA-R) have not been administered within the past four months, they will be administered at the screening visit. Information on the patient's concomitant medications, medical, surgical, ophthalmological history, family health history and other relevant history will be collected, as well as information on both the patient's and the study partner's demographics. The patient's corrected near visual acuity will be checked. Auditory acuity at various frequencies will be assessed using an audiometer. Fasting blood will be drawn, for analysis of HbA1c, CBC, electrolytes, creatinine, urea, lipid profile, glucose, liver function (AST, ALT, ALP, bilirubin), homocysteine, B12 and TSH. Blood will also be drawn for genomics and fluid biomarkers (see next section.)

Genomics and Fluid Biomarkers. Fasting blood samples for genetic testing including apoliprotein E4 status, as well as for proteomic, lipidomic and other fluid biomarkers of neurodegeneration and vascular disease, will be collected from each participant.

Neuropsychological Battery and Questionnaires. The cognitive battery comprises most of the tests used in the Ontario Neurodegenerative Disease Research Initiative (ONDRI) study, a new province-wide neurodegeneration research collaboration, with some modifications. It includes measures of executive function, memory, language, and visuospatial ability. Function, mood and behaviour, and caregiver burden will also be assessed using the questionnaires used in ONDRI. The full list of the assessment procedures is included in the BEAM neuropsychology manuals.

SD-OCT. Assessments to meet ocular criteria will include visual acuity, intra-ocular pressure (IOP) measurement and a non-mydriatic fundus camera recording, performed by a certified ophthalmic technician. The participant will then undergo SD-OCT to determine retinal nerve fiber layer thickness.

Vital Signs and Neurological Exam. Vital signs will be measured and a neurological examination will be performed.

Gait and Balance Assessment. Information on aid use and balance will be collected using questionnaires. Participants' leg length, calf circumference, height, and weight will be measured and recorded when possible.

Eye Tracking. Participants will be asked to look at a computer monitor and perform three sets of tasks (pro-saccade, anti-saccade, and dynamic free viewing) while a specialized camera tracks and records their eye movements. Participants who are unable to complete these assessments will be allowed to continue participation in the study.

SV-OCT at Sunnybrook. SV-OCT will be done in subsamples with high SVD vs. minimal SVD loads. A rapid (\>100 fps) 3D scanning protocol will be applied to SD-OCT, allowing acquisition of speckle variance due to microscopic blood flow in the retinal vasculature. Image processing using GPU based technique will provide real-time assessment of microvasculature morphology.

MRI. 3DT1 SPGR, interleaved spin echo PD/T2 and FLAIR to assess SVD, and gradient echo images to assess microbleeds, will be obtained on the 3 Tesla scanners at each of the TDRA sites. The PD/T2 and FLAIR images are co-registered to the T1-weighted image to remove non-brain tissues to determine total supratentorial intracranial volume to correct for head size, classify brain tissue compartments and automatically identify subcortical and white matter hyperintensities using a published in-house pipeline, "Lesion Explorer", which with manual editing yields number, size, location, and volume of the hyperintensities. For hippocampal volume, we use our fully automated segmentation pipeline based on a template library registration117, 118. We will also acquire DTI to generate total and regional fractional anisotropy (FA) and Mean Diffusivity Maps, using FSL and DTI tool box, and a resting state fMRI to explore Default Mode Network (DMN) connectivity, using a processing pipeline steps previously applied to AD patients and controls119.

Arterial Spin Labeling (ASL) will be included at certain sites which are capable of acquiring this sequence, to obtain measures of regional cerebral perfusion.

Amyloid PET. PIB, labelled with the positron emitting atom carbon-11, is a radiotracer that targets Aβ-aggregates (β-amyloid) in vivo. β-amyloid deposits are present in the brain of patients with Alzheimer's Disease (AD). Therefore, Aβ-plaques in the brain may be a useful biomarker of the disease and its progression and \[11 C\]-PIB may be a useful tool to detect these plaques in the human living brain with PET.

\[11 C \]-PIB is an investigational positron emitting radiopharmaceutical (PER) not yet marketed in Canada. The ligand will be manufactured at CAMH PET centre. PET imaging will be performed using \[11 C\] PIB at CAMH PET Centre with PET/CT-Discovery MI scanner using the standardized acquisition protocol.

The PET imaging protocol begins with a low dose CT scan (less than 0.05 mSv) for attenuation correction. Immediately following this acquisition, a bolus containing approximately 10 ± 1 mCi of \[11 C\]-PIB is administered by IV injection, followed by 90 minutes acquisition. Acquisition and reconstruction of PET images are done according to the standard PET Centre Imaging Protocols.

Phone Check Ups: For safety measures the participants will be contacted by phone to discuss any possible adverse event and general well-being two times during the course of the study:

* 24-72 hours after the PET scan

* 30 days (+/- 7 days) after PET Scan and/or the last study procedure

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
345
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Normal ControlsPittsburgh Compound B [11C]-PIBUpto 85 normal elders, 50-90 years old who are within normal limits on the study neuropsychological battery will be enrolled. All patients involved in the study will undergo SD-OCT, eye tracking, gait and balance assessments, blood draw for genomics and fluid biomarkers, neuropsychological assessment, brain MRI and brain amyloid PET.
Mild Cognitive Impairment (VCI)Pittsburgh Compound B [11C]-PIBSixty-five subjects meeting the National Institute on Aging-Alzheimer's Association criteria for amnestic or multi-domain MCI with MoCA score ≥18 will be enrolled. All patients will undergo SD-OCT, eye tracking, gait and balance assessments, blood draw for genomics and fluid biomarkers, neuropsychological assessment, brain MRI and brain amyloid PET. A subset will undergo SV-OCT.
Alzheimer's Disease (AD)Pittsburgh Compound B [11C]-PIBSixty-five subjects meeting the National Institute on Aging-Alzheimer's Association (NIA-AA) core clinical criteria for probable AD dementia will be enrolled. All patients will undergo SD-OCT, eye tracking, gait and balance assessments, blood draw for genomics and fluid biomarkers, neuropsychological assessment, brain MRI and brain amyloid PET. A subset will undergo SV-OCT.
Subcortical Vascular Impairment (VCI)Pittsburgh Compound B [11C]-PIBSixty-five subjects meeting the American Heart Association-American Stroke Association (AHA-ASA) criteria for probable vascular dementia (VaD) or probable vascular mild cognitive impairment (VaMCI) due to subcortical ischemic vascular disease , and probable or possible Cerebral Amyloid Angiopathy using the Modified Boston Criteria116 will be enrolled. All patients will undergo SD-OCT, eye tracking, gait and balance assessments, blood draw for genomics and fluid biomarkers, neuropsychological assessment, brain MRI and brain amyloid PET. A subset will undergo SV-OCT.
LBD SpectrumPittsburgh Compound B [11C]-PIBSixty- five subjects with: Dementia with Lewy Bodies (DLB) meeting the criteria for probable Dementia with Lewy Bodies with MMSE score ≥20; or PD-MCI meeting the proposed Level I criteria for Mild Cognitive Impairment in Parkinson's Disease with MoCA score 18-24; or; PDD meeting the criteria for probable Parkinson's Disease - Dementia and MMSE score ≥20 will be enrolled. All patients involved will undergo SD-OCT, eye tracking, gait and balance assessments, blood draw for genomics and fluid biomarkers, neuropsychological assessment, brain MRI and brain amyloid PET. A subset will undergo SV-OCT.
Primary Outcome Measures
NameTimeMethod
Retinal nerve fiber layer thicknessOne-time assessment

This potential ocular biomarker will compared among the different cohorts and be validated against brain MRI and brain amyloid PET.

Amyloid DepostitionOne-time assessment

This will be compared among the different cohorts and be validated against brain amyloid PET, and are expected to correlate meaningfully with cognitive and behavioural patterns, including retinal and eye-tracking, gait and balance.

Secondary Outcome Measures
NameTimeMethod
Retinal artery narrowingOne-time assessment

The extent of correlation between retinal artery narrowing and the presence of covert lacunar infarcts on MRI will be assessed.

Retinal venular wideningOne-time assessment

The extent of correlation between retinal venular widening and the amount of periventricular white matter hyperintensities on MRI will be assessed.

Trial Locations

Locations (5)

Sunnybrook Health Sciences Centre

🇨🇦

Toronto, Ontario, Canada

St. Michael's Hospital

🇨🇦

Toronto, Ontario, Canada

Baycrest Health Sciences

🇨🇦

Toronto, Ontario, Canada

University Health Network

🇨🇦

Toronto, Ontario, Canada

Centre for Addiction and Mental Health (CAMH)

🇨🇦

Toronto, Ontario, Canada

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