Japanese men in Japan had a significantly lower prevalence of coronary artery calcification (PR 0.52; 95% CI 0.35-0.76) and lower carotid intima-media thickness than White men in the US.
Cross-Sectional (n=493)
Yes
Is there a difference in the prevalence of subclinical atherosclerosis between Japanese men in Japan and White men in the US aged 40-49 years?
Japanese men in Japan have significantly less subclinical atherosclerosis than White men in the US despite a less favorable risk factor profile, supporting the 'Japanese paradox'.
Relative Risk: 0.52 (95% CI 0.35–0.76)
Coronary heart disease incidence and mortality remain very low in Japan despite major dietary changes and increases in risk factors that should have resulted in a substantial increase in coronary heart disease rates (Japanese paradox). Primary genetic effects are unlikely, given the substantial increase in coronary heart disease in Japanese migrating to the United States. For men aged 40-49 years, levels of total cholesterol and blood pressure have been similar in Japan and the United States throughout their lifetimes. The authors tested the hypothesis that levels of subclinical atherosclerosis, coronary artery calcification, and intima-media thickness of the carotid artery in men aged 40-49 years are similar in Japan and the United States. They conducted a population-based study of 493 randomly selected men: 250 in Kusatsu City, Shiga, Japan, and 243 White men in Allegheny County, Pennsylvania, in 2002-2005. Compared with the Whites, the Japanese had a less favorable profile regarding many risk factors. The prevalence ratio for the presence of a coronary calcium score of > or =10 for the Japanese compared with the Whites was 0.52 (95% confidence interval: 0.35, 0.76). Mean intima-media thickness was significantly lower in the Japanese (0.616 mm (standard error, 0.005) vs. 0.672 (standard error, 0.005) mm, p < 0.01). Both associations remained significant after adjusting for risk factors. The findings warrant further investigations.
Sekikawa et al. (2007) conducted a cross-sectional in Subclinical atherosclerosis (n=493). Japanese men in Japan vs. White men in the United States was evaluated on Presence of a coronary calcium score of ≥10 (PR 0.52, 95% CI 0.35-0.76). Japanese men in Japan had a significantly lower prevalence of coronary artery calcification (PR 0.52; 95% CI 0.35-0.76) and lower carotid intima-media thickness than White men in the US.