Coronary risk factors influence plaque morphology in patients with unstable angina

Background The risk of plaque disruption and subsequent thrombosis in patie nts with unstable angina depends on the plaque type and size. Design Intravascular ultrasound (IVUS) was employed to illustrate the corre lation between risk factors and plaque morphology in patients with unstable angina. Methods In a prospective study of 60 of 95 patients consecutively admitted with unstable angina [41 men, aged 61.2 +/- 8.1 years (mean +/- SD)], quali tative (soft and hard plaque, thrombus, calcification, eccentricity, adapti ve and constrictive remodeling) and quantitative [lumen, external elastic m embrane (EEM) and plaque cross-sectional area (CSA) and plaque burden] IVUS data relating to the target lesion, and proximal and distal reference segm ents were analyzed and correlated with risk factors. Univariate and multiva riate nominal logistic regression analyses and analyses of variance were us ed to determine the independent predictors for IVUS morphology. Results For plaque composition univariate analysis showed a younger age (<6 0 years) to be a predictor for adaptive: remodeling (P=0.019), and an older age to be a predictor for constrictive remodeling (P=0.021). Hypercholeste rolemia, smoking and sex were associated with a higher frequency of thrombu s (P=0.044, 0.038 and 0.043, respectively). Multivariate analyses revealed that only younger and older ages were independent predictors for adaptive a nd constrictive remodeling (P=0.039 and P=0.045). For plaque size, univaria te and multivariate analyses demonstrated that diabetes mellitus and hyperc holesterolemia were independent predictors for greater plaque (13.5 +/- 5.7 2 versus 10.17 +/- 4.6 mm(2) P=0.015, for diabetic versus non-diabetic pati ents; 12.0 +/- 5.35 vers us 9.03 +/- 3.76 mm(2), P=0.010, for hypercholeste rolemic versus normocholesterolemic patients) and EEM CSA (17.16 +/- 5.81 v ersus 14.3 +/- 5.1 mm(2), P=0.033, for diabetic versus non-diabetic patient s; 16.57 +/- 5.49 versus 12.25 +/- 3.8 mm(2), P=0.001, for hypercholesterol emic versus normocholesterolemic patients) at the target lesion. Hyperchole sterolemia was associated with significantly greater plaque and EEM CSA in both proximal and distal reference segments. Conclusions Multivariate analyses indicated that age, diabetes and hypercho lesterolemia are independent predictors for plaque morphology in patients w ith unstable angina Coronary Artery Dis 10:211-219 (C) 1999 Lippincott Will iams & Wilkins.