C-Reactive Protein Is an Independent Predictor of the Rate of Increase in Early Carotid Atherosclerosis

Abstract

Background —An elevated plasma concentration of high-sensitivity C-reactive protein (hs-CRP) is a strong predictor of cardiovascular events. However, there have been no longitudinal studies of the relations between development of atherosclerotic lesions and hs-CRP concentrations. Furthermore, it remains unknown whether increased hs-CRP concentrations result in the development of atherosclerosis. Methods and Results —The study included 179 outpatients 40 to 79 years of age who were treated at our institute for traditional risk factors for cardiovascular disease. The patients had no evidence of advanced carotid atherosclerosis at the time of baseline examination. Patients underwent repeated ultrasonographic evaluation of the carotid arteries for 35±10 months. Blood samples were collected for hs-CRP measurements. Based on focal intima-media thickening ≥1.1 mm representing plaque, plaque number (PN) and plaque score (PS; the sum of all plaque thicknesses) were calculated. The development of atherosclerosis was estimated by the formula Δvalue/year=(last value−baseline value)/number of follow-up years. Multivariate linear regression analysis revealed that the log-transformed value for hs-CRP concentration was not related to baseline PN or PS but was related to ΔPN/year and ΔPS/year (β=0.29 and 0.30; P <0.001 for both) independently of the effect of traditional risk factors. Conclusions —During the early stages of carotid atherosclerosis, the hs-CRP concentration is a marker of carotid atherosclerotic activity rather than extent of atherosclerosis.