Article

Differences in endothelial function between Korean-Asians and Caucasians

Department of Physical Therapy, School of Allied Health Professions, Loma Linda University, Loma Linda, CA 92350, USA.
Medical science monitor: international medical journal of experimental and clinical research (Impact Factor: 1.43). 06/2012; 18(6):CR337-43. DOI: 10.12659/MSM.882902
Source: PubMed

ABSTRACT

The vascular endothelium plays an integral role in maintaining vascular homeostasis, including the regulation of blood flow, vascular tone, and platelet aggregation. The aim of this study was to see if there were any differences in endothelial function between Koreans and Caucasians.
This was accomplished by 2 measures of endothelial function--the response to local heat and the response to vascular occlusion. Ten Caucasian and 10 Korean male and female subjects participated (<35 years old). Endothelial function was assessed by the skin blood flow response to local heat using a thermode for 6 minutes at 3 temperatures (38°C, 40°C and 42°C) and by vascular occlusion for 4 minutes followed by release and measurement of skin blood flow for 2 minutes.
When applying 6 minutes of local heat at 3 different temperatures (38°C, 40°C, and 42°C), the skin blood flows were significantly higher for all temperatures in Caucasians as compared with Koreans, with peak blood flow of 223±48.1, 413.7±132.1, and 517.4±135.8 flux in Caucasians and 126.4±41.3, 251±77.9, and 398±97.2 flux in Koreans, respectively (p=0.001). Results of this study support the idea that the skin blood flow response to occlusion was significantly higher in Caucasians (peak 411.9±88.9 flux) than Koreans (peak 332.4±75.8 flux) (p=0.016).
These findings suggest that Koreans may have lower endothelial function than Caucasians, which may be explained, in part, by genetic variations between the 2 ethnic groups.

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    • "Finally, three of the RCTs were conducted among Koreans and 1 RCT among Caucasians [6–9] and it is unclear if the findings are applicable to other countries or ethnic groups. A recent very small study showed that endothelial function, which plays an important part in vascular tone, regulating blood flow, and platelet function, may be lower in Koreans than Caucasians [32]. Furthermore, genetic polymorphism of CYP2C19 was shown to be an independent predictor of clopidogrel resistance in Korean subjects with coronary artery disease [33]. "
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    • "In previous studies, we and others have shown that the endothelial response seen in Asians newly arrived to the US is lower than that seen in age-matched Caucasians [1–4]. Further, in Native born Koreans, when oxidative markers in the blood were measured, the impaired endothelial response in Koreans, as measured by MDA, was inversely related to endothelial function [3]. "
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