Cohorts     Targeted population Number of  participants/follow-up Biobank Imaging and exams
SHIVA (ongoing recruitment) Hypertensive patients (aged 60 to 88), with a memory complaint

200 patients with extensive cSVD vs 200 patients with minimal cSVD

3 years follow-up

Blood, DNA, RNA
  • 3T Brain MRI (N~800)
  • SS-OCT-A and AO imaging (N~800)
Memento Non-demented patients with an isolated cognitive complaint or mild to moderate cognitive impairment

2,323 patients deficits from 28 French memory clinics

≥ 5 years follow-up

Blood, DNA, RNA, CSF
  • Brain MRI (N~5,000)
  • Amyloid PET (N~669)
  • FDG PET optional (N~3,000)
  • Retinophoto. & OCT (N~400)
  • Cardio exams
i-Share Healthy students

~19,000 participants from French Universities

10 years follow-up

Blood, DNA
  • 3T Brain MRI (N~1,900)
  • Retinophoto. & OCT-A & AO (N~400)
  • GWAS (N~1,800), WGS (N~600)
B cube Population-based cohort aged 55 to 80 2,000 French participants in Bordeaux Blood, urine, stool, saliva, hair, nails, nasal swabs
  • 3T Brain MRI (N~500)
Three City (3C) Population-based cohort aged 65+ (non-institutionalized individuals)

9,693 participants : 4,931 from Dijon + 2,104 from Bordeaux + ~2,259 from Montpellier

12 years follow-up

Blood, DNA
  • 1.5T brain MRI
  • Retinophoto. & OCT (N~2,500)
  • Cardiologic exams
  • >6,500 genome-wide, 500 WES, 400 WGS
Valiant Population-based cohort aged 50+ ~1,000 Nigerian participants Blood, DNA
  • Brain MRI
  • Genetic

The B cube cohort is a population-based cohort of 2,000 French individuals, aged 55 to 80, randomly selected on electoral lists of Bordeaux or its metropole, from neighborhoods contrasted in terms of socio-economic status. It aims at investigating the determinants and natural history of brain aging using molecular epidemiology (analysis of 2000 metabolites) with an extensive biobank (blood, urine, stool, saliva, hair, nails, nasal swabs). The overarching ambition of B cube is to establish a next-generation etiological research platform using high throughput molecular and cutting-edge neuroimaging approaches, to shed light to the complex etiology of cognitive aging and related diseases. A focus is given on nutrition and lifestyle, yet environmental exposures at large (the exposome), including psychosocial factors and chemical exposures, are also evaluated. An ancillary neuroimaging study is funded for n=500 participants.

The SHIVA cohort is a national comparative multicenter study following up over 3 years a cohort of 2 groups of 200 older hypertensive patients (aged between 60 and 88 years), with a memory complaint (with or without objective cognitive deficits but without advanced dementia), frequency-matched on age (by 5-years strata) and sex. The first group will consist of patients with little or no white matter hyperintensities on brain MRI (no or minor feature of cSVD); while the second will include patients with moderate to severe white matter hyperintensities (MRI feature of extensive cSVD). This study aims to explore the relation of brain and retinal microvasculature image characteristics (imaging biomarkers), as well as molecular biomarkers derived from blood, with presence or absence of extensive cSVD and with cognitive and other clinical characteristics in 400 patients 60+ years of age.

The Three City (3C) study is a population-based cohort of 9,693 French non-institutionalized individuals, aged 65+, randomly selected from electoral rolls of Dijon, Bordeaux and Montpellier. Participants benefited from detailed clinical examination with prospective ascertainment of incident events (including stroke, dementia). ~2,000 participants from 3C-Dijon and ~1,000 participants from 3C-Bordeaux underwent at least one 1.5T brain MRI; OCT and retinophotography was performed in ~2,500 participants. Genome-wide genotypes are available in >6,500 participants and in 3C-Dijon whole exome sequencing (WES) in 500 and whole genome sequencing (WGS) in 400. Ancillary studies include measurements of blood pressure variability, pulse wave velocity, carotid ultrasound.

The Memento cohort includes 2,323 non-demented participants with ean isolated cognitive complaint or mild to moderate cognitive deficits, recruited consecutively in 28 French memory clinics, and followed-up annually for >5 years. At enrolment and every 2 years, a brain MRI and blood samples (DNA/RNA) are performed, genome-wide genotypes are available for all pa rticipants; amyloid positron emission tomography (PET) is performed in 669 participants (other optional investigations include FDG PET and lumbar puncture). An ancillary study (VASCOD, N~400) exploring the role of vascular disease on cognitive decline includes among other measurements retinophotography, OCT, and pulse wave velocity. Principles and rules for data sharing are well established and help maximize the use of Memento.

The i-Share Study is a prospective cohort study on students’ health run in several French universities. Over 19,000 students have been included of whom ~1,900 students have participated in ancillary studies including 3T brain MRI and blood sampling with genome-wide genotypes available in all and WGS in 600. Retinophotography and OCT are also performed. This provides a lifetime perspective of cSVD biomarker progression over the lifespan.

The Valiant cohort: Globally, the proportion of global burden of disease that is attributable to brain health disorders is expected to rise partly because of the projected increase in the proportion of older adults. This rise will be steeper in low- and middle- income countries although it is not fully understood why individuals of African ancestry are more prone to vascular cognitive disorders and frailty. To explore this intriguing research question, we have established the Vascular heAlth, fraiLty and cognItion in Ageing Nigerians sTudy (VALIANT), a rigorous population-based cohort study aimed at exploring the association between cardiovascular health and cognition and frailty in Nigeria using a longitudinal design. 1,000 participants selected by multistage, stratified cluster random sampling method are being recruited from the population over a six month period (November 2022 - April 2023) and taken through a battery of cardiovascular, cognitive and fragility assessment tools. Neuroimaging (MRI), biochemical and genetic analysis are anticipated through partnership with the VHBI Study. On a long term, VALIANT offers opportunity to study the genetics, epigenetics, biomarkers and intermediate phenotypes of vascular brain disease and thus contribute to understanding the neurobiology and mechanisms of vascular cognitive brain disorders and frailty in a population of African ancestry.