Abstract P238: Cardiovascular Risk Factors for Intimal and Medial Calcification in a High-risk Population

Abstract

Introduction: Arterial calcification is associated with an increased cardiovascular risk. Intimal calcification has long been held responsible for this association, whereas the role of medial calcification was unclear. Hypothesis: We hypothesize that the risk factor profile in patients with high cardiovascular risk differs for those with intimal or medial calcification of the lower extremity arteries. Methods: We conducted a cross-sectional study of 203 patients included in the Second Manifestations of ARTerial Disease (SMART) study, comprising of patients with CVD as well as patients at high risk for CVD, who underwent CT (computed tomography) scanning of the lower extremities. Calcification in the femoral and crural arteries was scored as absent, dominant intimal, dominant medial or indistinguishable according to a previously validated algorithm scoring linearity and circularity. We fitted multinomial regression models assessing the associations of cardiovascular risk factors with different patterns of calcification. Results: No calcification was present in 18% for the femoral and 28% for the crural arteries, while prevalence of intimal calcification was 44% and 38%. Medial calcification prevalences were 25% and 20% for the femoral and crural arteries, respectively. We found considerable consistency in the predominant calcification pattern of the crural and femoral arteries (linear weighted Cohen’s kappa [0.41, 95%CI 0.29-0.52]). Patients with dominant medial calcification were older, more often male and more often had diabetes than patients with intimal calcification. Conversely, patients with intimal calcification were more often smokers than patients with medial calcification. In multinomial logistic regression models, age was a significant risk factor for all types of calcification compared with no calcification. Male sex was associated with an increased risk of medial calcification [OR femoral 10.37, 95%CI 2.14-50.32], but not with intimal or indistinguishable calcification, compared with no calcification. Current smoking was associated with intimal calcification[OR femoral 3.25, 95%CI 0.98;10.83], but not with medial calcification. No significant relationships were found with other cardiovascular risk factors. Conclusions: Within the same individual, a predominant arterial calcification type (intimal or medial) often exists throughout the lower extremity. These patterns of calcification appear to have different associated risk factor profiles.