Comparing coronary artery cross-sectional area among asymptomatic South Asian, White, and Black participants: the MASALA and CARDIA studies.

BACKGROUND: South Asian individuals have high risk of atherosclerotic cardiovascular disease (ASCVD). Some investigators suggest smaller coronary artery size may be partially responsible. METHODS: We compared the left anterior descending (LAD) artery cross-sectional area (CSA) (lumen and arterial wall) among South Asians in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) study with White and Black participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study, adjusting for BMI, height, and other ASCVD risk factors. We used thin-slice non-contrast cardiac computed tomography to measure LAD CSA. We used linear regression models to determine whether race/ethnicity was associated with LAD CSA after adjusting for demographic factors, BMI, height, coronary artery calcium (CAC), and traditional cardiovascular risk factors. RESULTS: Our sample included 3,353 participants: 513 self-identified as South Asian (44.4% women), 1286 as Black (59.6% women), and 1554 as White (53.5% women). After adjusting for age, BMI, height, there was no difference in LAD CSA between South Asian men and women compared to White men and women, respectively. After full adjustment for CVD risk factors, LAD CSA values were: South Asian women (19.9 mm2, 95% CI [18.8 - 20.9]) and men (22.3 mm2, 95% CI [21.4 - 23.2]; White women (20.0 mm2, 95% CI [19.4-20.5]) and men (23.6 mm2, 95% CI [23.0-24.2]); and Black women (21.6 mm2, 95% CI [21.0 - 22.2]) and men (26.0 mm2, 95% CI [25.3 - 26.7]). Height, BMI, hypertension, CAC, and age were positively associated with LAD CSA; current and former cigarette use were inversely associated. CONCLUSIONS: South Asian men and women have similar LAD CSA to White men and women, and smaller LAD CSA compared to Black men and women, respectively, after accounting for differences in body size. Future studies should determine whether LAD CSA is associated with future ASCVD events.

Association of volumetric bone mineral density with abdominal aortic calcification in African ancestry men.

SUMMARY: We tested for association between cortical and trabecular volumetric bone mineral density (vBMD) with abdominal aortic calcification (AAC) prevalence in 278 Afro-Caribbean men. AAC was present in 68.3 % of the men. Greater cortical, but not trabecular, vBMD was associated with significantly decreased odds of AAC independent of traditional risk factors. INTRODUCTION: The aim of this study is to assess the prevalence and correlates of AAC in a sample of 278 Afro-Caribbean men (mean age 56) and to test for a largely unexplored association between cortical and trabecular vBMD with AAC prevalence. METHODS: Men were recruited consecutively as part of an ongoing prospective cohort study of body composition in men aged 40+. For this analysis, AAC was assessed by computed tomography of the abdomen from L3 to S1. Aortic calcium was scored using the Agatston method, and prevalence was defined as a score ≥10 to rule out false positives. Men also had BMD assessed using peripheral quantitative computed tomography at 4 % (trabecular vBMD) and 33 % (cortical vBMD) of the radius and tibia. RESULTS: Abdominal aortic calcification was present in 68.3 % of the men. Significant independent predictors of AAC prevalence were increased age, increased BMI, hypertension, and current smoking. Age was the strongest predictor, with each SD (7.8 year) increase in age conferring 2.7 times increased odds of having AAC (P < 0.0001). A one SD greater cortical, but not trabecular, vBMD was associated with a significant decreased odds of AAC prevalence independent of other traditional risk factors (OR 0.65; 95 % CI 0.45-0.92). CONCLUSIONS: Cortical vBMD is inversely associated with AAC presence. This finding suggests that there may be shared physiology between cortical bone compartment remodeling and vascular calcification.

Associations of risk factors with segment-specific intimal-medial thickness of the extracranial carotid artery.

BACKGROUND AND PURPOSE: It is generally assumed that risk factors affect extracranial carotid intimal-medial thickness similarly among all arterial segments. This assumption underlies use of single segments or walls of segments as outcome variables for risk factor studies and clinical trials. However, if the impact of risk factors was unequal for various segments or circumferentially asymmetrical within segments, then inferences drawn from a single segment or wall might not be generalizable; furthermore, since individual segments and walls have unique histological characteristics and are differentially exposed to turbulent flow, risk factor relationships with a particular segment or wall may provide inferences regarding pathogenesis of atherosclerosis. METHODS: We evaluated associations of risk factors with intimal-medial thickness at the near and far walls of the common carotid artery, bifurcation, and internal carotid artery in 280 individuals older than 45 years equally divided between coronary artery disease cases and controls and between men and women. RESULTS: The patterns of differences in mean intimal-medial thickness among segments vary, depending on age, history of hypertension, body mass index in women, and coronary (case-control) status. The asymmetry of disease depended on blood glucose concentrations, prior history of diabetes, smoking, and coronary status. Sex, postmenopausal status, LDL cholesterol, systolic blood pressure, and history of myocardial infarction all had statistically significant relationships with intimal-medial thickness that were fairly homogeneous among arterial sites. CONCLUSIONS: Focus on an individual segments or walls of the extracranial carotid arteries may lead to overestimation or underestimation of associations of risk factors with extracranial carotid intimal-medial thickness.

Apolipoprotein E polymorphism is associated with segment-specific extracranial carotid artery intima-media thickening.

BACKGROUND AND PURPOSE: Apolipoprotein E (apoE) polymorphism affects plasma cholesterol and may influence risk of atherosclerosis. We investigated the association of apoE with carotid artery wall thickening (an index of atherosclerosis) in individuals with and without coronary artery disease (CAD). METHODS: ApoE phenotypes were resolved in 260 individuals equally represented by angiographically determined CAD case subjects and disease-free control subjects. Carotid artery intima-media thickening (IMT) was evaluated by B-mode ultrasound. Associations of apoE (E2, E3, or E4) with risk factors and IMT were evaluated in general linear models adjusted for age, sex, and CAD status with and without other traditional risk factors. RESULTS: Total cholesterol (TC) and LDL cholesterol were associated with apoE isoforms. Mean TC and LDL cholesterol were lower in E2 (n = 33) carriers than E3 (n = 155) and E4 (n = 66) carriers (each P < .001). IMT also varied by apoE. E2 carriers had less common carotid IMT than E3 and E4 carriers (P < .01), while internal carotid IMT was less in E2 and E3 carriers than in E4 carriers (P < .02). Bifurcation IMT was not associated with apoE (P = .24). ApoE polymorphism remained associated with common (P < .01) and internal (P < .04) IMT, and the association of apoE with mean IMT of all sites reached significance (P < .04) after adjustment for age, sex, CAD status, TC, LDL cholesterol, HDL cholesterol, triglycerides, diabetes, hypertension, and smoking. CONCLUSIONS: ApoE polymorphism is associated with segment specific carotid IMT. The association of apoE with carotid IMT was statistically independent of apoE-associated variation in LDL cholesterol levels.

Gliomas in children following radiation therapy for lymphoblastic leukemia.

Four children treated for acute lymphoblastic leukemia developed intracranial gliomas between 40 and 120 months following multiagent chemotherapy, prophylactic whole brain irradiation, and intrathecal Methotrexate. The diagnosis of glioma was confirmed in each case with biopsy or autopsy. These children were part of a larger series of 73 patients with acute lymphoblastic leukemia treated at Indiana University receiving 24 Gy as per the protocol guidelines of the Children's Cancer Study Group. Currently 42 patients of the original 73 children survive in continuous remission.