Significance of Subclinical Atherosclerosis in Cardiovascular Risk Assessment

pp. 209-214

Abstract

Background: The current recommendation for risk stratification of the new ACC/AHA guidelines on cholesterol therapy to reduce atherosclerotic cardiovascular risk questions the usefulness of subclinical atherosclerosis detection in primary prevention.

Objectives: The aim of this study was to analyze the prevalence of subclinical atherosclerosis assessed by carotid echocardiography in the different risk groups according to the new guidelines, and to evaluate the prevalence of subclinical atherosclerosis in the different subgroups when a sub-stratification based on the number of risk factors is added.

Methods: Consecutive primary prevention patients were selected. Patients with a history of diabetes and/or coronary artery disease and/or peripheral vascular disease were excluded from the study. Subclinical atherosclerosis was defined as the presence of one or more atherosclerotic plaques detected by carotid Doppler echocardiography.

Results: Five hundred and forty one patients were analyzed; 243 (45%) were stratified as low risk, 100 (18%) as intermediate risk and 198 (37%) as high risk. The prevalence of plaque (subclinical atherosclerosis) was 12% (95% CI 9-17) in the low risk group, 23% (95% CI 16-32) in the intermediate risk group and 41% (95% CI 34-48) in the high risk group (p<0.001). When analyzing the different subgroups, the prevalence of subclinical atherosclerosis was 30% (95% CI 20-43) in the intermediate risk patients with two or more risk factors; however, in the subgroup with 0 to 1 risk factors, the prevalence was 14% (95%CI 6-27) (p<0.05).

Conclusions: Subclinical atherosclerosis assessment added to the number of risk factors can identify subjects with different risks beyond the stratification established by the new American guidelines, which can be useful when deciding individual therapeutic management.