The Three-City Study


The Three-City Study

The Three-City Study (3C Study) is a population-based longitudinal study of the relation between vascular diseases and dementia in persons aged 65 years and older.


A total of 9,294 participants (3,649 men and 5,645 women) were recruited from three French cities: Bordeaux (South-West), Dijon (North-East) and Montpellier (South-East).


The 3C Study started in 1999 and is planned to continue till 2012.


Participants underwent regular extensive examination. Examination included measurements of traditional vascular risk factors (blood pressure, glycaemia, lipids, etc.), cognitive functions, and subclinical vascular diseases using carotid ultrasound and cerebral magnetic-resonance imaging (MRI). Additional measurements such as echocardiography, 24h- dietary recall, assessment of vision, and walking performance, just to mention some of them, were performed in ancillary studies.


The main outcomes are dementia (Alzheimer’s disease and other types of dementia), vascular diseases (coronary heart disease and stroke), and mortality.