Blood pressure parameters and carotid intraplaque hemorrhage as measured by magnetic resonance imaging: The Rotterdam Study

Abstract

Intraplaque hemorrhage (IPH) is a characteristic of the vulnerable atherosclerotic plaque that has been associated with ischemic stroke. Not much is known about determinants of IPH. We studied whether blood pressure parameters are associated with presence of IPH. Within the framework of a prospective population-based cohort study, The Rotterdam Study, the carotid arteries of 1006 healthy participants ≥45 years and with intima-media thickening (≥2.5 mm) on ultrasound were imaged with a 1.5-T magnetic resonance imaging scanner. IPH was defined as a hyperintense signal on a 3D-T1w-GRE magnetic resonance sequence. Generalized estimation equation analysis, adjusted for age, sex, carotid wall thickness, and cardiovascular risk factors, was used to assess the association between blood pressure parameters and IPH. Magnetic resonance imaging of the carotid arteries revealed presence of IPH in 444 of 1860 plaques (24%). Systolic blood pressure and pulse pressure (PP) were significantly associated with IPH after adjustment for age and sex. In multivariate analysis, PP yielded the strongest association, with an odds ratio per SD increase in PP of 1.22 (95% CI, 1.07-1.40). The odds ratio per SD for systolic blood pressure was 1.13 (0.99-1.28). Only PP remained significant after additional adjustment for other blood pressure components. The combination of smoking and isolated systolic hypertension was associated with 2.5 times increased risk of IPH (1.2-5.2). In conclusion, PP was the strongest determinant of IPH independent of cardiovascular risk factors and other blood pressure components. The association between pulsatile flow and IPH may provide novel insights in the development of the vulnerable plaque.