Objectives To examine whether marine-derived n-3 fatty acids (FAs) are associated with less atherosclerosis in Japanese than Whites in the United States. Background Marine-derived n-3 FAs at low levels are cardioprotective through their anti-arrhythmic effect. Methods 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. Results 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). Conclusions 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.

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.

Visceral adipose tissue (VAT) is an independent risk factor for metabolic and cardiovascular disorders. There has been no study that demonstrated different abdominal fat distribution between Asian and Caucasian men. As the Japanese are less obese but more susceptible to metabolic disorders than Caucasians, they may have larger VAT than Caucasians at similar levels of obesity. We compared the abdominal fat distribution of the Japanese (n ¼ 239) and Caucasian-American (n ¼ 177) men aged 40-49 years in groups stratified by waist circumference in a population-based sample. We obtained computed tomography images and determined areas of VAT and subcutaneous adipose tissue (SAT). We calculated VAT to SAT ratio (VSR). The Japanese men had a larger VAT and VSR in each stratum, despite substantially less obesity overall. In multiethnic studies, difference in abdominal fat distribution should be considered in exploring factors related to obesity. International Journal of Obesity (2006) In these studies, VAT was compared after adjusting for other factors such as age and obesity. There has been no report directly comparing VAT between the Japanese and Caucasian men in a population-based sample. Therefore, we compared the abdominal fat distribution of the Japanese and Caucasian-American men aged 40-49 years in groups stratified by waist circumference in a population-based sample. We recruited 240 American men aged 40-49 years (Caucasians: 82%), randomly selected from Allegheny County, Pennsylvania, US, and 240 Japanese men aged 40-49 years, randomly selected from Kusatsu, Shiga, Japan. We confined our analyses to Caucasian and Japanese men, because African men have been compared with Caucasians elsewhere, 6 and we had only one man who categorized himself as neither Caucasian nor African-American. In order to compare the abdominal adipose tissue (AAT) distribution at similar levels of waist circumference, participants with extremely large or small waist circumference (beyond the levels of mean 72 (s.d.)) were excluded from the present analysis. After excluding 44 non-Caucasian-Americans and 20 outliers in waist circumference, 416 (239 Japanese and 177 Caucasian) men were examined. Waist circumference

Women with polycystic ovary syndrome (PCOS) exhibit an adverse cardiovascular risk profile, characteristic of the metabolic cardiovascular syndrome (MCS). The aim of this study was to determine the prevalence of coronary artery (CAC) and aortic (AC) calcification among middle-aged PCOS cases and controls and to explore the relationship among calcification, MCS, and other cardiovascular risk factors assessed 9 yr earlier. This was a prospective study of 61 PCOS cases and 85 similarly aged controls screened in 1993-1994 for risk factors and reevaluated in 2001-2002. The main outcome measures were CAC and AC, measured by electron beam tomography. Women with PCOS had a higher prevalence of CAC (45.9% vs. 30.6%) and AC (68.9% vs. 55.3%) than controls. After adjustment for age and body mass index, PCOS was a significant predictor of CAC (odds ratio = 2.31; P = 0.049). PCOS subjects were also 4.4 times more likely to meet the criteria for MCS than controls. High-density lipoprotein cholesterol and insulin appeared to mediate the PCOS influence on CAC. Interestingly, total testosterone was an independent risk factor for AC in all subjects after controlling for PCOS, age, and body mass index (P = 0.034). We conclude that women with PCOS are at increased risk of MCS and demonstrate increased CAC and AC compared with controls. Components of MCS mediate the association between PCOS and CAC, independently of obesity.

We studied the relationship of coronary artery calcification (CAC), a marker of coronary atherosclerosis, with prevalent clinical coronary artery disease (CAD) and established cardiovascular disease (CVD) risk factors in a type 1 diabetic population. At the 10-year follow-up examination of the Pittsburgh Epidemiology of Diabetes Complications (EDC) Study cohort, 302 adults (mean age 38.1 ± 7.8 years) received electron beam tomography (EBT) scanning of the heart and a clinical examination. Clinical CAD was defined as a confirmed history of myocardial infarction (MI), angiographic stenosis ≥50%, Pittsburgh EDC Study physician-diagnosed angina, or ischemic electrocardiogram (ECG). CAC correlated with most CVD risk factors. CAC had 84 and 71% sensitivity for clinical CAD in men and women, respectively, and 100% sensitivity for MI or obstructive CAD. A CACS cut point of 400 was the most efficient coronary calcium correlate of CAD. In subjects with angina only, CAC sensitivity was 83% in men and 46% in women. In logistic regression, CAC, ECG R-R variation, peripheral vascular disease, and Beck Depression Inventory independently correlated with prevalent CAD in men and overall. Except for CAC, the same variables independently correlated with CAD in women, and age also entered the model. CAC was an independent correlate of MI or obstructive CAD in both sexes and was the strongest independent correlate in men, but CAC was not independently associated with angina and ischemic ECG in either sex. It is concluded that EBT-detected CAC is strongly correlated with CAD in type 1 diabetes-particularly in men.