Intima-media thickness of the carotid artery and the distribution of lipoprotein subclasses in men aged 40–49 between whites in the U.S. and the Japanese in Japan for the ERA JUMP Study

摘要

In men in the post World War II birth cohort, i.e., men aged 40–49, whites in the United States (U.S.) had significantly higher levels of intima-media thickness of the carotid arteries (IMT) than the Japanese in Japan. The difference remained after adjusting for traditional risk factors. Primary genetic effects are unlikely, given the degree to which IMT is increased in the Japanese who migrated to the U.S. We investigated whether the differences in the distributions of lipoprotein subclasses explain the difference in IMT between the two populations. We examined population-based samples of 466 randomly-selected men aged 40–49 (215 whites from Allegheny County, U.S., and 241 Japanese from Kusatsu, Japan). Lipoprotein subclasses were determined by nuclear magnetic resonance (NMR) spectroscopy. The whites had significantly higher levels of large very-low-density-lipoprotein particles and significantly lower levels of large high-density-lipoprotein particles than the Japanese, whereas the two populations had similar levels of small low-density-lipoprotein particles. The two populations had similar associations of IMT with NMR lipoproteins. Adjusting for NMR lipoproteins did not attenuate the significant difference in IMT between the two populations (0.671 ± 0.006 for the whites and 0.618 ± 0.006 mm for the Japanese, P=0.01, mean (standard error)). Differences in the distributions of NMR lipoproteins between the two populations did not explain the higher IMT in the whites.