Type 2 diabetes does not attenuate racial differences in coronary calcification.

AIMS: Coronary artery calcification (CAC) is a strong predictor of atherosclerotic cardiovascular disease (CVD). Whites appear to have a higher prevalence of CAC than African-Americans (AAs), but it is unknown if type 2 diabetes, a major cardiovascular risk factor, attenuates this difference. We investigated the relationship of race and CAC in a sample of patients with type 2 diabetes without clinical CVD. METHODS: multivariable analyses of self-reported ethnicity and CAC scores, stratified by gender, in 861 subjects [32% AA, 66.9% male] with type 2 diabetes. RESULTS: AA race was associated with lower CAC scores in age-adjusted models in males [Tobit ratio for AAs vs. Whites 0.14 (95% CI 0.08-0.24, p<0.001)] and females [Tobit ratio 0.26 (95% CI 0.09-0.77, p=0.015)]. This persisted in men after adjustment for traditional, metabolic and inflammatory risk factors, but adjustment for plasma triglycerides [0.48 (95% CI 0.15-1.49, p=0.201)] and HOMA-IR [0.28 (95% CI 0.08-1.03, p=0.055)] partially attenuated the association in women. CONCLUSIONS: relative to African-Americans, White race is a strong predictor of CAC, even in the presence of type 2 diabetes. The relationship in women appears less robust possibly due to gender differences in metabolic risk factors.

Quantitative angiography in South Asians reveals differences in vessel size and coronary artery disease severity compared to Caucasians.

South Asians are one of the highest risk ethnic groups for development of coronary artery disease (CAD) mortality and morbidity. Previous studies have investigated whether South Asians exhibit differences in angiographic coronary artery disease compared to Caucasians, with inconsistent results. We conducted a retrospective observational study comparing South Asians undergoing cardiac catheterization at a tertiary care institution with Caucasians who underwent catheterization at the same time and location to assess whether South Asians demonstrated smaller coronary artery size and/or increased angiographic coronary artery disease. Demographic and laboratory data were retrospectively abstracted. Quantitative coronary angiographic analysis of all three coronary arteries was performed using the edge-detection method. South Asian patients were younger (57 versus 64 years, p=0.004) and showed higher prevalences of diabetes, dyslipidemia, and acute coronary syndrome compared with Caucasians (40% versus 16%, p=0.004; 65% versus 46%, p=0.04; and 37% versus 10%, p<0.001; respectively). South Asians exhibited smaller normalized proximal LAD luminal diameters (1.56 versus 1.72 mm/m(2), p=0.04) when compared to Caucasians. South Asians also displayed more severe CAD as determined by both increased mean percent stenosis in the proximal LAD and RCA segments (22.7% versus 11.1%, p=0.004; and 24.5% versus 13.9%, p=0.0001, respectively) as well as a higher number of patients with multiple diseased vessel segments. South Asians demonstrated more severe CAD compared to Caucasians undergoing cardiac catheterization as evidenced by smaller proximal LAD luminal diameters, higher mean percent stenosis per vessel, and more patients with multivessel disease. Further study is warranted to better define factors important in the development of CAD and inform risk stratification in this high-risk population.

Association of lower plasma fetuin-a levels with peripheral arterial disease in type 2 diabetes.

OBJECTIVE: Fetuin-A is an inhibitor of vascular calcification and a mediator of insulin resistance. This study evaluated the association of plasma fetuin-A and peripheral arterial disease (PAD). RESEARCH DESIGN AND METHODS: A total of 738 individuals with type 2 diabetes (mean age 58.7 years, 37.1% female) without known cardiovascular or kidney disease were included in this cross-sectional analysis. RESULTS: Subjects with PAD had a significantly lower fetuin-A (264.3 vs. 293.4 ng/dl, P < 0.001). In multivariable analysis, a 1-SD decrease in fetuin-A increased the odds of PAD (odds ratio 1.6, P = 0.02). Subgroup analysis revealed an increased odds even in subjects with glomerular filtration rate >80 (odds ratio 1.9, P = 0.05) or high-sensitivity C-reactive protein <3 mg/dl (odds ratio 2.7, P = 0.002). CONCLUSIONS: Lower circulating fetuin-A is associated with PAD in type 2 diabetes beyond traditional and novel cardiovascular risk factors. Our findings suggest a potentially unique role for fetuin-A deficiency as a biomarker of PAD in patients with type 2 diabetes.