IMPORTANCE Coronary artery calcium (CAC), measured by computed tomography (CT), has strong predictive value for incident cardiovascular disease (CVD) events. The standard CAC score is the Agatston, which is weighted upward for greater calcium density. However, some data suggest increased plaque calcium density may be protective for CVD.OBJECTIVE To determine the independent associations of CAC volume and CAC density with incident CVD events. DESIGN, SETTING, AND PARTICIPANTS Multicenter, prospective observational MESA study (Multi-Ethnic Study of Atherosclerosis), conducted at 6 US field centers of 3398 men and women from 4 race/ethnicity groups; non-Hispanic white, African American, Hispanic, and Chinese. Participants were aged 45-84 years, free of known CVD at baseline, had CAC greater than 0 on their baseline CT, and were followed up through October 2010.MAIN OUTCOMES AND MEASURES Incident coronary heart disease (CHD) and all CVD events RESULTS During a median of 7.6 years of follow-up, there were 175 CHD events and an additional 90 other CVD events for a total of 265 CVD events. With both lnCAC volume and CAC density scores in the same multivariable model, the lnCAC volume score showed an independent association with incident CHD, with a hazard ratio (HR) of 1.81 (95% CI, 1.47-2.23) per standard deviation (SD = 1.6) increase, absolute risk increase 6.1 per 1000 person-years, and for CVD an HR of 1.68 (95% CI, 1.42-1.98) per SD increase, absolute risk increase 7.9 per 1000 person-years. Conversely, the CAC density score showed an independent inverse association, with an HR of 0.73 (95% CI, 0.58-0.91) per SD (SD = 0.7) increase for CHD, absolute risk decrease 2.0 per 1000 person-years, and an HR of 0.71 (95% CI, 0.60-0.85) per SD increase for CVD, absolute risk decrease 3.4 per 1000 person years. Area under the receiver operating characteristic curve analyses showed significantly improved risk prediction with the addition of the density score to a model containing the volume score for both CHD and CVD. In the intermediate CVD risk group, the area under the curve for CVD increased from 0.53 (95% CI, 0.48-0.59) to 0.59 (95% CI, 0.54-0.64), P = .02.CONCLUSIONS AND RELEVANCE CAC volume was positively and independently associated with CHD and CVD risk. At any level of CAC volume, CAC density was inversely and significantly associated with CHD and CVD risk. The role of CAC density should be considered when evaluating current CAC scoring systems.

Background Small studies have shown that South Asians (SAs) have more total body, subcutaneous, visceral and hepatic fat and abnormal adipokine levels compared to Whites. However, comprehensive studies of body composition and adipokines in SAs compared to other ethnic groups are lacking. Methods Using harmonized data, we performed a cross-sectional analysis of two community-based cohorts: Mediators of Atherosclerosis of South Asians Living in America (MASALA, n=906) and Multi-Ethnic Study of Atherosclerosis (MESA which included 2,622 Whites; 803 Chinese Americans; 1,893 African Americans; and 1,496 Latinos). General linear models were developed to assess ethnic differences in ectopic fat (visceral, intermuscular, and pericardial fat; and hepatic attenuation), lean muscle mass, and adipokines (adiponectin and resistin). Models were adjusted for age, sex, site, alcohol use, smoking, exercise, education, household income and BMI. Ectopic fat models were additionally adjusted for hypertension, diabetes, HDL, and triglycerides. Adipokine models were adjusted for subcutaneous, visceral, intermuscular, and pericardial fat; and hepatic attenuation. Results Compared to all ethnic groups in MESA (Whites, Chinese Americans, African Americans, and Latinos), SAs had greater intermuscular fat (pairwise comparisons to each MESA group, p < 0.01), lower hepatic attenuation (p < 0.001), and less lean mass (p < 0.001). SAs had greater visceral fat compared to Chinese Americans, African Americans and Latinos (p < 0.05) and greater pericardial fat compared to African Americans (p < 0.001). SAs had lower adiponectin levels compared to other ethnic groups (p < 0.01; except Chinese Americans) and higher resistin levels than all groups (p < 0.001), even after adjusting for differences in body composition. Conclusion There are significant ethnic differences in ectopic fat, lean mass, and adipokines. A less favorable body composition and adipokine profile in South Asians may partially explain the increased predisposition to cardiometabolic disease. The mechanisms that underlie these differences warrant further investigation.

Albuminuria and reduced eGFR associate with two apolipoprotein L1 gene (APOL1) variants in non-diabetic African Americans. Whether APOL1 associates with subclinical atherosclerosis and survival remains unclear. To determine this, 717 African American-Diabetes Heart Study participants underwent computed tomography to determine coronary artery, carotid artery, and aorta calcified atherosclerotic plaque mass scores in addition to the urine albumin:creatinine ratio (UACR), eGFR, and C-reactive protein. Associations between mass scores and APOL1 were assessed adjusting for age, gender, African ancestry, BMI, HbA1c, smoking, hypertension, use of statins and ACE inhibitors, albuminuria, and eGFR. Participants were 58.9% female with mean age 56.5 years, eGFR 89.5 ml/min/1.73m2, UACR 169.6 mg/g, coronary artery, carotid artery and aorta calcified plaque mass scores of 610, 171 and 5378, respectively. In fully adjusted models, APOL1 risk variants were significantly associated with lower levels of carotid artery calcified plaque (β −0.42, SE 0.18, dominant model), and marginally lower coronary artery plaque (β −0.36, SE 0.21; dominant model), but not with aorta calcified plaque, C-reactive protein, UACR, or eGFR. After a mean follow-up of 5.0 years, 89 participants died. APOL1 nephropathy risk variants were significantly associated with improved survival (hazard ratio 0.67 for 1 copy; 0.44 for 2 copies). Thus, APOL1 nephropathy variants associate with lower levels of subclinical atherosclerosis and reduced risk of death in African Americans with type 2 diabetes mellitus.

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Background The relationship between body weight and cardiometabolic disease may vary substantially by race/ethnicity. Objective To determine the prevalence and correlates of the phenotype of metabolic abnormality but normal weight (MAN) for 5 racial/ethnic groups. Design Cross-sectional analysis. Setting 2 community-based cohorts. Participants 2622 white, 803 Chinese American, 1893 African American, and 1496 Hispanic persons from MESA (Multi-Ethnic Study of Atherosclerosis) and 803 South Asian participants in the MASALA (Mediators of Atherosclerosis in South Asians Living in America) study. Measurements Prevalence of 2 or more cardiometabolic abnormalities (high fasting glucose, low high-density lipoprotein cholesterol, and high triglyceride levels and hypertension) among normal-weight participants was estimated. Correlates of MAN were assessed by using log-binomial models. Results Among normal-weight participants (n = 846 whites, 323 Chinese Americans, 334 African Americans, 252 Hispanics, and 195 South Asians), the prevalence of MAN was 21.0% (95% CI, 18.4% to 23.9%) in whites, 32.2% (CI, 27.3% to 37.4%) in Chinese Americans, 31.1% (CI, 26.3% to 36.3%) in African Americans, 38.5% (CI, 32.6% to 44.6%) in Hispanics, and 43.6% (CI, 36.8% to 50.6%) in South Asians. Adjustment for demographic, behavioral, and ectopic body fat measures did not explain racial/ethnic differences. After adjustment for age, sex, and race/ethnicity–body mass index (BMI) interaction, for the equivalent MAN prevalence at a BMI of 25.0 kg/m2 in whites, the corresponding BMI values were 22.9 kg/m2 (CI, 19.5 to 26.3 kg/m2) in African Americans, 21.5 kg/m2 (CI, 18.5 to 24.5 kg/m2) in Hispanics, 20.9 kg/m2 (CI, 19.7 to 22.1 kg/m2) in Chinese Americans, and 19.6 kg/m2 (CI, 17.2 to 22.0 kg/m2) in South Asians. Limitation Cross-sectional study design and lack of harmonized dietary data between studies. Conclusion Compared with whites, all racial/ethnic minority groups had a statistically significantly higher prevalence of MAN, which was not explained by demographic, behavioral, or ectopic fat measures. Using a BMI criterion for overweight to screen for cardiometabolic risk may result in a large proportion of racial/ethnic minority groups being overlooked. Primary Funding Source National Institutes of Health.