Carotid artery intima-media thickness: normal and percentile values in the Italian population (camp study)

Aims: Carotid intima-media thickness (IMT) is one of the best non-invasive parameters for evaluating previous vascular lesions and could be used to identify a preclinical stage of the atherosclerotic process. The aim of our research was to develop an epidemiological study of the normal mean values of IMT of the common carotid artery, adjusted for age and sex, in the Italian population. Methods and results: In this multicenter study, a total of 1017 patients (596 males, mean age: 58.5 + 13.2 years) were enrolled at four different Italian centers. Inclusion criteria were the absence of cardiovascular risk factors or presence of not more than one. Patients underwent two-dimensional echo-color Doppler scanning of the carotid arteries, adopting a high-definition vascular echographic apparatus and a 11-3 MHz linear electronic probe. The arithmetical mean of the IMT value was calculated. Data obtained from this study show the carotid IMT changes in relation to age and sex. In particular, it grows higher with increasing age, and is always higher in men than in women. Conclusion: In relation to the percentile distribution of the values in the population analyzed, the normal range of m-IMT could be established just on the basis of the patient's age and sex. In this way, the ultrasound scan operator can rely on a simple reference scheme. This will help to refine the use of carotid ultrasound as an excellent tool for detecting asymptomatic carotid alterations and patients at high risk for cerebral and cardiovascular disease.