Carotid atherosclerosis is an important risk factor for stroke, cognitive impairment and dementia. The carotid ultrasound Study and the Tromsø Dementia Study are two sub-studies of the Tromsø Study, a large, longitudinal population health study which was started in 1974.
The study includes repeated measurements of both ultrasound-assessed carotid aterhosclerosis (assessed in 1994-95 and 2001) and of cognitive functioning (2001). We are currently planning the sixth Tromsø survey to take place in 2007-8. We will invite all subjects still alive who had previos ultrasound measurements in 1994-5 and/or 2001, approx. 4500 persons. New measurements of carotid atherosclerosis and cognitive function will be performed.
This allows analysis of cognitive function a nd decline in relation to the whole spectre of carotid atherosclerotic changes, from early intima-media thickening to advanced stenosis.