The Atherosclerosis Risk in Communities Study (ARIC) is a prospective epidemiologic study conducted in four U.S. communities. ARIC is designed to investigate the etiology and natural history of atherosclerosis, the etiology of clinical atherosclerotic diseases, and variation in cardiovascular risk factors, medical care and disease by race, gender, location, and date. Since 2011 a large ancillary study, the ARIC Neurocognitive Study (ARIC-NCS) has been assessing neurocognitive status and adjudicating possible cases of dementia.

Four ARIC field centers each randomly selected and recruited a cohort sample of approximately 4,000 individuals aged 45-64 from a defined population in their community. A total of 15,792 participants received an extensive baseline examination (visit 1, 1987-1989), including medical, social, and demographic data collection. Subsequent examinations occurred in 1990-92 (visit 2), 1993-95 (visit 3), 1996-98 (visit 4), 2011-2013 (visit 5) and 2016-2017 (visit 6). Visit 7 (2018-2019) is currently in progress. Follow-up occurs annually (semi-annually since 2012) by telephone to maintain contact with participants and to assess health status of the cohort.

The health of the agricultural population has been previously explored, particularly in relation to the farming exposures and among professionally active individuals. However, few studies specifically focused on health and aging among elders retired from agriculture. Yet, this population faces the long-term effects of occupational exposures and multiple difficulties related to living and aging in rural area (limited access to shops, services, and practitioners). However, these difficulties may be counter-balanced by advantages related to healthier lifestyle, richer social support and better living environment. The general aim of the AMI cohort was to study health and aging in elderly farmers living in rural area through a multidisciplinary approach, with a main focus on dementia.

The study started in 2007, with two follow-up visits over 5 years. Baseline visits were conducted at home by a neuropsychologist then by a geriatrician for all cases suspected of dementia, for all subjects suspected of being demented. The 10-year visit is currently on going.

The main objective of the FINGER study is to find out if a multi-domain intervention could prevent cognitive decline among older people. With this intervention we also aim to investigate the effect of the multidomain intervention on disability, quality of life, depressive symptoms, the use of health care services and vascular risk factors.

Participants of the FINGER study have previously taken part in population-based non-intervention studies. They have an increased risk of cognitive decline. At the beginning of the study they are 60-77 years old. The FINGER study enrols approximately 1200 participants in six centers in Finland: Helsinki, Kuopio, Oulu, Seinäjoki, Turku and Vantaa.

This project comprises of two complementary parts. One part is aimed at the development of innovative diagnostic techniques to detect molecular signatures of AD based on disturbances of amyloid metabolism and glutamate neurotransmission. In this part, the focus is on the two most promising diagnostic approaches in AD: (molecular) imaging techniques and molecular diagnostic tests of CSF. In the second part of this study, techniques for which proof-of-concept has been found in humans are applied in a large group of AD patients. These patients are recruited in an established network of 4 collaborating memory clinics in The Netherlands, which use a standardized diagnostic protocol and share an extensive common database. Furthermore, more mature molecular, structural, and functional imaging and molecular diagnostic CSF techniques as well as the conventional diagnostic work-up will be applied from the start of the study in patients from the same network of memory clinics.

The Mayo Clinic Study of Aging was designed to establish a prospective population-based cohort of subjects to study prevalence, incidence and risk factors for MCI and dementia. The study was conducted in Olmsted County, where several factors enhance the feasibility of population-based epidemiologic research. Most residents seek care within the community from essentially 2 providers, the Mayo Clinic and Olmsted Medical Center, along with their affiliated hospitals and medical facilities within the county. Both healthcare providers use a unit medical record which includes all outpatient and inpatient information for each patient. The study began October 1, 2004, and recruitment is ongoing to maintain a sample size of about 3,000 active participants. Participants are randomly selected from the Olmsted County population using a sex and age-stratified sampling scheme. Selected participants are invited to participate; exclusion criteria are persons who are in hospice or terminally ill or demented, but recruitment of persons with dementia began in 2015. Nearly 6,000 participants have been recruited to date. At the onset of the study, only 70-89 year olds were eligible. Recruitment of 50-69 year-olds began in 2012, and recruitment of 30-49 year olds began in 2014. Followup is performed every 15 months for 50 yrs and older; every 30 months if younger than 50 years by face-to-face visits in the Center, in-home, or by phone for a minority who decline either of the two but still would like to participate. Medical records are reviewed is used to identify prevalent and incident medical conditions (e.g. vascular diseases such as diabetes, hypertension) and incident dementia cases among persons lost to follow-up.

The ADC was setup in 2004 by including all patients who come to the Alzheimer Center for diagnostic work up and who consent to give all data, collected as part of the routine diagnostic work up, for research. The aim is and was to facilitate research into new and existing biomarkers in the broadest sense, to establish diagnostic, prognostic and theragnostic values and further insight into the pathogenesis of neurodegenerative dementias. The data are collected on a weekly basis and consist of baseline data and annual follow up data. Since it is conception it has grown into one of the largest clinical databases in the dementia field. More info on setup, characteristics and data collection can be found in van der Flier WM, Pijnenburg YA, Prins N, Lemstra AW, Bouwman FH, Teunissen CE, van Berckel BN, Stam CJ, Barkhof F, Visser PJ, van Egmond E, Scheltens P.

Optimizing patient care and research: the Amsterdam Dementia Cohort. J Alzheimers Dis. 2014;41(1):313-27. doi: 10.3233/JAD-132306. PubMed PMID: 24614907.

Last Update 21/09/2017

The Swedish BioFINDER Study consists of four cohorts where patients are included prospectively and followed longitudinally ( At baseline, these individuals undergo detailed and standardized cognitive, neurological and psychiatric examinations. Plasma, blood, CSF and samples for cell biology studies are collected. Most also have also undergone advanced Magnetic Resonance Imaging, and in many of the non-demented cases Amyloid and Tau positron emission tomography (PET) imaging have also been done.

The subcohorts include:
i) Healthy volunteers. Ca 350 volunteers aged 60-100 years old from the population-based Malm’ EPIC cohort (380 participants as of Feb 2016). Follow-up time: at least 8 years with investigations repeated every second year. In this cohort, appr. 20% is expected to have preclinical AD.
ii) Patients with Mild Cognitive Impairment (MCI) or Subjective Cognitive Decline (SCD). Ca 500 patients with MCI/SCD aged 60-80 years. Follow-up time: at least 6 years with investigations repeated every year. In this cohort, appr. 50% is expected to have prodromal AD.
iii) Patients with different dementia disorders. We include ca 250 dementia cases aged 40-100 years with AD, VaD, DLB, PDD or FTD. Follow-up time: at least 2 years with investigations repeated every year.
IV) Patients with Parkinson’s disease (PD) and PD-related disorders. Ca 300 patients with Parkinson-like symptoms. Follow-up time: at least 6 years with investigations repeated every year.

Last Update 21/09/2017

STROKOG is a consortium of longitudinal studies of cognitive disorders following stroke, TIA or small vessel disease. Developed under the auspices of VASCOG (Society for the Study of Vascular Cognitive and Behavioural Disorders), it is the first international effort to harmonise work on post-stroke dementia and is being led by CHeBA researchers.

The consortium brings together studies that have examined post-stroke or other high vascular risk cohorts longitudinally, with cognitive decline and dementia (including sub-types) as primary outcome variables. The included studies (N=27; total sample of more than 10,000 individuals, representing 17 countries) have rich neuropsychological and MRI data, and some recent studies (n=3) have included amyloid imaging in sub-samples. A number of studies have CSF and/or plasma available for biomarker studies, and participant enrolment in brain banks for neuropathology.

Last Update 21/09/2017

AIBL is a study of over 2,000 people assessed over a long period of time (over 10 years) to determine which biomarkers, cognitive characteristics, and health and lifestyle factors determine subsequent development of symptomatic Alzheimer’s Disease (AD).

The baseline inception cohort consisted of:
i. 211 individuals with AD as defined by NINCDS-ADRDA (McKhann et al, 1984);
ii. 133 individuals with Mild Cognitive Impairment (MCI)
iii. 768 healthy individuals without cognitive impairment. This group included volunteers with at least one copy of the ApoE ?4 allele, volunteers without a copy of the ApoE ?4 allele and 396 volunteers who expressed subjective concern about their memory function.

The enrichment cohort consists of:
i. 142 individuals with AD
ii. 220 individuals with MCI
iii. 582 individuals with without cognitive impairment.

The data was collected through clinics and questionnaires.

Last Update 21/09/2017

The aim of the Alfa Study is to focus on the processes taking place before the initiation of Alzheimer’s symptoms in order to design interventions to prevent or delay the onset of dementia. Inclusion criteria were being cognitively normal Spanish and/or Catalan-speaking persons aged between 45 and 74 years that agreed with the study procedures and tests: clinical interview and questionnaires associated to risk factors, cognitive tests, a blood sample extraction for DNA analysis, and MRI.

A subset (n=450) of the ALFA parent cohort participants are currently being recruited / undergoing a nested longitudinal long-term study, named the ALFA+ study, in which a more detailed phenotyping will be performed. On top of a similar characterization as in the ALFA parent cohort, it will entail the acquisition of both wet (CSF, blood, and urine sample collection) and imaging (magnetic resonance imaging [MRI] and PET) biomarkers. Furthermore, ALFA parent cohort participants may also be invited to participate in other BBRC studies such the ALFAlife primary intervention study (n=400) or the full genetic and neuroimaging characterisation study referred to as ALFAgenetics (n=2000).

Last Update 21/09/2017