One hundred and twenty-five randomly chosen active and retired employees of the state of Styria without signs or history of a cerebrovascular disease volunteered in a field study designed to determine the prevalence of asymptomatic carotid artery disease (ACAD) in this population and to examine its relation to cerebrovascular risk factors and possible morphologic and metabolic changes of the brain reflected by CT scanning and CBF measurements. The cohort consisted of 82 men and 43 women, the mean age was 49.6 years (range 24-75). High-resolution Duplex scanning revealed minimal to moderate atherosclerotic carotid plaques in 37/125 probands (29.6%). Univariate analysis without age correction showed significant differences in the incidence of a number of risk factors in the groups with and without ACAD. When controlling for age and sex, multivariate analysis identified, besides higher age (p = 0.0002), elevated fibrinogen (p = 0.02) and mildly impaired CBF (p = 0.02) to be significantly associated with the presence of ACAD.