Distribution of Cervicocephalic Atherosclerotic Lesions and Their Correlation with Cardiovascular Risk Factors in a Population of Amerindians. The Atahualpa Project

Abstract

BackgroundNo information is available on the distribution of cervicocephalic atherosclerosis in Amerindians. We aimed to assess the distribution of these lesions and their correlation with cardiovascular risk factors in Amerindians living in rural Ecuador. MethodsAtahualpa residents aged ≥40years underwent head CT for assessment of carotid siphon calcifications (CSC) and sonographic examination for measurement of the carotid intima media thickness (cIMT). CSC were used as a surrogate of intracranial atherosclerosis and the cIMT as a surrogate of extracranial atherosclerosis. Linear regression and multinomial logistic regression models were fitted to assess the association between cIMT and CSC, and to evaluate differences in risk factors across individuals with atherosclerosis involving both arterial beds when compared with those with extra- or intracranial atherosclerosis alone, or no atherosclerosis. ResultsOf 590 participants, 145 had high calcium content in the carotid siphons and 87 had a cIMT >1mm (25% versus 15%, P < .001). Thirty-eight (7%) individuals had atherosclerosis at both vascular beds, 107 (18%) had intracranial atherosclerosis, and 49 (8%) had extracranial atherosclerosis alone. The cIMT and CSC were independently associated (P = .008). When compared with participants without atherosclerosis, those with atherosclerosis at both vascular beds were older, more often male, hypertensive and diabetic. Subjects with intracranial atherosclerosis alone were older, and those with extracranial atherosclerosis alone reported less physical activity than those without atherosclerosis. ConclusionIntracranial atherosclerosis is more common than extracranial atherosclerosis in Amerindians. Traditional risk factors only explain a minority of cases of cervicocephalic atherosclerosis in this population.