Abstract 1731: Among Inflammatory Markers, E-Selectin and P-Selectin Are The Earliest To Index Atherosclerotic Plaque Regression During Lipid Lowering Therapy
Background: Elevated levels of cell surface adhesion molecules and other markers of inflammation are associated with the presence of atherosclerosis. In the present study, we have sought to determine whether reductions in serum markers of inflammation parallel alterations of carotid artery plaque architecture and size.
Methods: The internal carotid arteries (ICAs) of 82 subjects ≥65 years of age (63 males) with atherosclerosis of at least moderate severity in ≥ 1 vascular bed were imaged on a 1.5 T MR scanner at baseline, 6, and 12 months for a prospective clinical trial investigating the effects of lipid lowering therapy on carotid atherosclerosis. Five oblique slices of the thickest region of each ICA in T1-weighted (post-gadodiamide) images were obtained and vessel wall volume (cm3) was calculated. Levels of inflammatory markers were measured at each MRI visit by indirect enzyme-linked immunosorbent assays.
At 6 months: There was a statistically significant reduction in mean carotid wall volume (0.05±0.1 mm3, p=0.004), E-selectin (6.7±13.5 ng/ml, p=0.0026) and P-selectin levels (14.1±45.9 ng/ml, p=0.047). Multivariate analysis after adjusting for age, gender, smoking, hypertension, diabetes, and family history of heart disease, showed that reduction in carotid wall volume was significantly and positively related to reduction in E-selectin (0.008 ng/ml , p<0.001) and P-selectin (0.009 ng/ml, p<0.001) levels. No significant associations were found for CRP, IL-6, ICAM-1 or TNF-α.
At 12 months: There was a statistically significant reduction in mean carotid wall volume (0.1±0.12 mm3, p=0.0001), E-selectin (10.53±19.5 ng/ml, p=0.007), P-selectin (17.96±40 ng/ml, p=0.047) and ICAM-1 (21.7±49.5 ng/ml, p=0.021). Multivariate analysis showed that reduction in carotid wall volume was significantly and positively related to reduction in E-selectin (0.0083 ng/ml, p=0.001), P-selectin (0.0079 ng/ml, p=0.001) and ICAM-1 (0.0073 ng/ml, p=0.001). No significant associations were found for CRP, IL-6 or TNF-α.
Conclusions: There is a statistically significant association with reduction in carotid wall volume and reduction in selectins as well as ICAM-1, but only reduction in E- and P-selectin parallel plaque regression as early as 6 months.