Abstract 11242: Clopidogrel Improves Endothelial Function in Healthy Individuals With Heightened Platelet Aggregation
Introduction: Platelet activation can lead to enhanced oxidative stress, inflammatory response and endothelial dysfunction. To quantify the effects of platelet inhibition on endothelial function, we assessed platelet activity of healthy individuals before and after clopidogrel administration and evaluated its effects on endothelial function.
Hypothesis: We hypothesized that clopidogrel, by attenuating platelet activity, would result in enhanced endothelial function.
Methods: Microcirculatory endothelial function was quantified by thermal hyperemia (TH) and post-occlusive reactive hyperemia (PORH) laser Doppler flowmetry (LDF) in 287 and 241 relatively healthy and homogenous Old Order Amish individuals, respectively. LDF and platelet aggregation measures were obtained at baseline and after 7 days of clopidogrel administration. Our primary outcome was percent change in post- versus pre-clopidogrel LDF measures.
Results: Pre-clopidogrel TH-LDF and platelet aggregation were higher in women than men (p<0.001). Clopidogrel administration was associated with an approximately twofold higher percent change in TH-LDF, in subjects with high compared to low baseline platelet aggregation (39.4%±10.1 vs. 17.4%±5.6, p=0.03). Clopidogrel also increased absolute TH-LDF measures in individuals with high platelet aggregation (1757.2 ± 765.6 to 2153.8 ± 1054.5, p=0.03), with a more prominent effect in women (1909.4 ± 845.7 to 2518.1 ± 1047.9, p=0.001). There was no evidence that clopidogrel influenced PORH-LDF measures.
Conclusions: The administration of clopidogrel, in healthy individuals with high baseline platelet aggregation, results in improved TH-induced microcirculatory endothelial function. These data suggest that clopidogrel may have a beneficial effect on microcirculatory endothelial function, presumably through anti-platelet activity, and may confer additional vascular benefits.
Author Disclosures: S. Salimi: None. J.P. Lewis: None. L. Yerges-Armstrong: None. B.D. Mitchell: None. J.R. O’Connell: None. A.R. Shuldiner: None. A. Parsa: None.
- © 2016 by American Heart Association, Inc.