Marine-Derived n-3 Fatty Acids and Atherosclerosis in Japanese, Japanese-American, and White Men

To examine whether marine-derived n-3 fatty acids (FAs) are associated with less atherosclerosis in Japanese than Whites in the United States. Marine-derived n-3 FAs at low levels are cardioprotective through their anti-arrhythmic effect. A population-based cross-sectional study in 281 Japanese, 306 White, and 281 Japanese American men aged 40–49 was conducted to assess intima-media thickness of the carotid artery (IMT), coronary artery calcification (CAC), and serum FAs. Japanese in Japan had the lowest levels of atherosclerosis whereas Whites and Japanese Americans had similar levels. Japanese in Japan had twofold higher levels of marine-derived n-3 FAs than Whites and Japanese Americans. Japanese in Japan had significant and non-significant inverse associations of marine-derived n-3 FAs with IMT and CAC prevalence, respectively. The significant inverse association with IMT remained after adjusting for traditional cardiovascular risk factors. Neither Whites nor Japanese Americans had such associations. Significant differences between Japanese in Japan and Whites in multivariable-adjusted IMT (mean difference 39 μm (95% confidence interval (CI), 21 to 57), p<0.001) and CAC prevalence (mean difference 10.7% (95% CI, 2.9 to 18.4), p=0.007) became non-significant after further adjusting for marine-derived n-3 FAs (22 μm (95% CI, −1 to 46), p=0.065 and 5.0 % (95% CI, −5.3 to 15.4), p=0.341, respectively). Very high levels of marine-derived n-3 FAs have anti-atherogenic properties independent of traditional cardiovascular risk factors and may contribute to lower burden of atherosclerosis in Japanese in Japan, which is unlikely due to genetic factors. Keywords: Atherosclerosis, epidemiology, n-3 fatty acids, coronary artery calcification, intima-media thickness, Japanese