ASSOCIATION BETWEEN CAROTID-ARTERY BIFURCATION DISEASE AND RISK-FACTORS FOR ATHEROSCLEROSIS

Patients referred to the vascular laboratory for carotid duplex scanni ng may have identifiable risk factors for atherosclerosis. The presenc e of these risk factors may be associated with a higher risk of signif icant carotid bifurcation atherosclerosis. Furthermore, physicians hav e widely varying thresholds for requesting duplex scanning, and patien t characteristics are likely to be highly variable from one vascular l aboratory to another. The authors examined the relationship between si gnificant carotid disease and atherosclerotic risk factors in patients referred to a community hospital vascular laboratory. Complete inform ation was available for selected atherosclerotic risk factors includin g gender, diabetes, hypertension, cigarette smoking, cardiac disease, and prior stroke for 68 men and 78 women undergoing initial carotid du plex scanning between 4/1/93 and 11/11/93. The authors examined the po ssible correlation of these risk factors with the presence of severe c arotid disease (greater than or equal to 50% stenosis including intern al carotid occlusion) in at least one distal common carotid artery, bu lb, or proximal internal carotid. Severe disease was present in 34 (23 %) of 146 patients. Patients with severe carotid disease tended to be older (76.2 +/- 1.3 vs 73.4 +/- 0.9 years, mean +/- SEM), but this dif ference was not significant (P = 0.11). Patients with severe carotid d isease tended to have more total risk factors (3.2 vs 2.1, P < 0.01). Hypertension was the best predictor of severe carotid disease (36% wit h, 10% without hypertension, P < 0.01). Trends toward greater likeliho od of severe carotid disease in men, smokers, and in patients with car diac disease were not significant. Risk factors may be valuable predic tors of the presence or absence of significant carotid bifurcation dis ease. Hypertension and the total number of atherosclerotic risk factor s were strong predictors of significant carotid disease in the laborat ory. However, patient characteristics in individual vascular laborator ies may be highly skewed and vastly different from other vascular labo ratories and the population. Individual vascular laboratories should t abulate atherosclerotic risk factors in addition to indications for ca rotid duplex scanning so that the importance of these risk factors in each laboratory may be determined.