Multi-Ethnic Study Of Atherosclerosis Participants Research Articles

Associations of neighborhood problems and neighborhood social cohesion with mental health and health behaviors: The Multi-Ethnic Study of Atherosclerosis

Few studies have investigated the specific features implicated in neighborhood–health associations. We examined associations between measures of neighborhood problems and neighborhood social cohesion with depression, smoking, drinking, and walking for exercise in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Neighborhoods were characterized according to participant self-report and aggregated measures based on other MESA participants. Individuals living in the least problematic neighborhoods were significantly less likely to be depressed, to smoke, or to drink. Less socially cohesive neighborhoods were associated with increased depression, smoking, and not walking for exercise. Results persisted after adjusting for individual-level variables. Each measure appeared to capture distinct features of the neighborhood and associations did not differ by race/ethnicity. Results for neighborhood problems were robust to the use of aggregate measures but results for social cohesion generally were not. Future work should determine the health effect of modifying specific features of the neighborhood context.

Risk Factor Associations With the Presence of a Lipid Core in Carotid Plaque of Asymptomatic Individuals Using High-Resolution MRI

Atheroma vulnerability to rupture is increased in the presence of a large lipid core. Factors associated with a lipid core in the general population have not been studied. The Multi-Ethnic Study of Atherosclerosis (MESA) is a multicenter cohort study of individuals free of clinical cardiovascular disease designed to include a high proportion of ethnic minorities. We selected MESA participants from the top 15th percentile of maximum carotid intima media thickness by ultrasound and acquired high-resolution black blood MRI images through their carotid plaque before and after the intravenous administration of gadodiamide (0.1 mmol/kg). Lumen and outer wall contours were defined using semiautomated analysis software. We analyzed only plaques with a maximum thickness >or=1.5 mm by MRI (n=214) and assessed cross-sectional risk factor associations with lipid core presence by multivariable logistic regression. A lipid core was present in 151 (71%) of the plaques. After controlling for age, ethnicity, sex, maximum arterial wall thickness, hypertension, cigarette smoking, diabetes, and C-reactive protein, compared with participants in the lowest tertile of total plasma cholesterol, the ORs of having a lipid core for participants in the middle and highest tertiles were 2.76 (95% CI: 1.01 to 7.51) and 4.63 (95% CI: 1.56 to 13.75), respectively. None of the other risk factors was associated with lipid core. In persons with thickened carotid walls, plasma total cholesterol, but not other established coronary heart disease risk factors, is strongly associated with lipid core presence by MRI. High total cholesterol may be associated with rupture proneness of atherosclerotic lesions in the general population.

Associations between two common polymorphisms in the ABCA1 gene and subclinical atherosclerosis: Multi-Ethnic Study of Atherosclerosis (MESA)

Objective ABCA1 controls the first step in reverse cholesterol transport. The potential associations between G1051A (R219K) and −565C/T genetic polymorphisms in the ABCA1 gene, high-density lipoprotein cholesterol (HDL-C) and subclinical cardiovascular disease in the general population remains unclear. We examined these associations in a sample of Multi-Ethnic Study of Atherosclerosis (MESA) participants. Methods Nine hundred and sixty-nine MESA participants were genotyped and underwent CT examinations for coronary artery calcification (CAC) and carotid ultrasound examinations for intima media thickness. Genetic association analyses were performed. Results The AA genotype was associated with a 2.4 mg/dl higher HDL-C, adjusting for age, gender, race/ethnicity and clinic site ( p = 0.04). There was a 28% lower prevalence of CAC ( p = 0.002) in those with AA genotype that persisted after further adjustment for HDL-C. There were no significant associations between −565 C/T genotype and HDL-C. There were trends towards a higher prevalence of CAC in those with CT (PR = 1.13, p = 0.08) and TT (PR = 1.16, p = 0.08) genotypes, compared with CC genotype. Neither G1051A nor −565C/T polymorphisms were associated with carotid intima media thickness. Conclusion The AA genotype of the G1051A polymorphism is associated with slightly higher HDL-C and lower prevalence of CAC and thus may protect against subclinical cardiovascular disease. The T allele of −565 C/T polymorphism may increase risk for subclinical cardiovascular disease.

Regional diastolic dysfunction in individuals with left ventricular hypertrophy measured by tagged magnetic resonance imaging—The Multi-Ethnic Study of Atherosclerosis (MESA)

Impairment of global diastolic function is considered to be the mechanism of congestive heart failure in individuals with preserved systolic left ventricular (LV) function. Left ventricular hypertrophy (LVH) is known to be a risk factor for congestive heart failure with preserved systolic function, and this process may begin as a regional process. We investigated whether regional LV diastolic function measured by magnetic resonance tagging is altered in asymptomatic participants of the MESA with LVH and preserved systolic LV function. Regional systolic and diastolic strain rates were calculated from strain data in 218 participants of the MESA study. Circumferential strain was calculated from the midwall layer of the septum, anterior, lateral, and inferior walls at mid-LV level. Global LV function measures were studied by magnetic resonance imaging in 4291 MESA participants. Left ventricular hypertrophy for men and women was defined from the MESA population using previously established Framingham criteria. Global systolic function was slightly less in the LVH (ejection fraction = 0.66 +/- 0.10) versus the non-LVH group (ejection fraction = 0.69 +/- 0.07, P < .001). Stepwise regression analyses showed a direct relationship between regional diastolic dysfunction and increasing LV mass. Regional systolic strain and strain rate measures from participants with LVH were not significantly different from those without LVH. However, regional diastolic strain rate was significantly reduced in participants with LVH (1.5 +/- 1.1 s(-1)) compared with the non-LVH group (2.2 +/- 1.1 s(-1), P < .001) regardless of age or sex. Left ventricular hypertrophy is associated with regional diastolic dysfunction in individuals without evidence of clinical cardiovascular disease and preserved systolic function. Magnetic resonance imaging tagging provides detailed quantification of regional diastolic function noninvasively.

The Relationship Between Blood Pressure and C-Reactive Protein in the Multi-Ethnic Study of Atherosclerosis (MESA)

The goal of this study was to determine the relationship between resting blood pressure (BP) and C-reactive protein (CRP) in a multi-ethnic cohort of men and women from the Multi-Ethnic Study of Atherosclerosis (MESA). Several investigators have observed elevated levels of CRP in individuals with hypertension. Hypertension prevalence varies considerably across ethnic groups. Important questions remain regarding whether the relationship between hypertension and CRP is similar across ethnic and gender subgroups. The MESA participants had CRP levels determined at the baseline clinical examination (N = 6,814). Hypertension, treated as a dichotomous variable (yes/no), was defined as a systolic or diastolic BP > or =140/90 mm Hg or a self-reported history of hypertension and use of antihypertensive medications. The geometric mean CRP in hypertensive participants was 2.3 +/- 0.07 mg/l compared with 1.6 +/- 0.07 mg/l among normotensive participants (p < 0.0001). The relative difference in CRP levels in hypertensives compared with normotensives was similar regardless of gender (13% in men and 13% in women). Ethnic comparisons showed that Chinese participants had the lowest CRP concentration but the largest difference in CRP by hypertension status (24%). Caucasians and African Americans had 10% to 15% higher CRP levels with hypertension, whereas Hispanics had no significant difference in CRP by hypertension status. This study confirms the existence of an independent association between hypertension and inflammation in both men and women. Ethnic group differences were evident, with the strongest association observed in Chinese participants and no difference in CRP levels by hypertension status in Hispanics.

Urine Albumin Excretion and Subclinical Cardiovascular Disease

We examined the association between urine albumin excretion (UAE) and common and internal carotid artery intima-media thickness (IMT), end-diastolic left ventricular (LV) mass, and coronary artery calcification (CAC) scores using data from the Multi-Ethnic Study of Atherosclerosis (MESA), a population-based study of 6814 adults aged 45 to 85 years without clinical cardiovascular disease (CVD). The mean age of the MESA participants was 62.7 years, 47% were male, and 15% had diabetes mellitus (DM). Sex-specific spot urine albumin/creatinine ratios were used to define 4 UAE categories: normal, high normal, microalbuminuria, and macroalbuminuria. CAC scores were log-transformed after adding 1 to all scores. Mean values of subclinical CVD measures were computed by level of UAE after adjustment for blood pressure, DM, and other covariates. After adjustment for all covariates, geometric mean CAC scores were higher among participants with high normal UAE (8.8; P=0.07), microalbuminuria (9.9; P=0.002), and macroalbuminuria (13.1; P=0.02) compared with normal UAE (7.4), but only microalbuminuria reached statistical significance. Mean LV mass (g/m2.7) was significantly higher in participants with high normal UAE (37.0; P=0.001), microalbuminuria (38.3; P< or =0.0001), and macroalbuminuria (42.3; P< or =0.0001) compared with normal UAE (36.0) after adjustment for all covariates. No significant difference in mean carotid IMT was found after adjustment for all covariates. Similar results were noted in MESA participants with and without DM. In conclusion, higher UAE, including levels below microalbuminuria, may reflect the presence of subclinical CVD among adults without established CVD.

Cardioprotective Effects of High-Density Lipoproteins

The fact that a low level of high-density lipoprotein (HDL) cholesterol is highly predictive of future cardiovascular events has been established in population studies beyond all reasonable doubt. Furthermore, the evidence is overwhelming that the relationship is one of cause and effect rather than an epiphenomenon, with numerous studies in animals demonstrating that HDL-raising interventions translate into profound reductions in atherosclerosis. Such interventions have included the infusion of both native and reconstituted HDLs into rabbit models of atherosclerosis, the overexpression of apolipoprotein (apo) A-I (the major HDL protein) in transgenic mice and rabbits, and the inhibition of cholesteryl ester transfer protein (CETP) in rabbits. See pages 1325 and 1426 Evidence that raising the level of HDLs is also antiatherogenic in humans is mounting, although there are still relatively few human studies that have directly tested the phenomenon. Fibrates, statins, and niacin all raise the level of HDL cholesterol, and treatment with each of these agents has been shown to be associated with a reduction in future cardiovascular events. Fibrates are especially effective in event reduction in people with insulin resistance or with other features of the metabolic syndrome, although the benefits cannot be explained in terms of the observed HDL raising.1 Statins are effective in reducing events in all subjects, but the benefits can be explained almost completely in terms of the achieved LDL lowering2; the contribution of a statin-induced elevation of HDL is difficult to evaluate. Niacin, the most effective of the currently available HDL-raising agents, has also been shown to reduce cardiovascular events, especially when coadministered with a statin3; but again, other properties of niacin may …

Racial/Ethnic differences in hypertension and hypertension treatment and control in the multi-ethnic study of atherosclerosis (MESA)

Most previous studies investigating the association between ethnicity and hypertension focused on differences between African Americans and whites and did not include other racial/ethnic groups such as Chinese or Hispanics. We used data from the Multi-Ethnic Study of Atherosclerosis (MESA), a population-based study of 6814 adults without clinical cardiovascular disease, to examine the association between ethnicity and hypertension and hypertension treatment among white, African American, Chinese, and Hispanic ethnic groups. The prevalence of hypertension, defined as systolic blood pressure (BP) <140 mm Hg and diastolic BP <90 mm Hg or self-reported treatment for hypertension, was significantly higher in African Americans compared to whites (60% v 38%; P < .0001), whereas prevalence in Hispanic (42%) and Chinese participants (39%) did not differ significantly from that in whites. After adjustment for age, body mass index, prevalence of diabetes mellitus, and smoking, African American (odds ratio [OR] 2.21; 95% confidence interval [95% CI] 1.91-2.56) and Chinese (OR 1.30; 95% CI 1.07-1.56) ethnicity were significantly associated with hypertension compared to whites. Among hypertensive MESA participants, the percentage of treated but uncontrolled hypertension in whites (24%) was significantly lower than in African Americans (35%, P < .0001), Chinese (33%, P = .003), and Hispanics (32%, P = .0005), but only African-American race/ethnicity remained significantly associated with treated but uncontrolled hypertension after controlling for socioeconomic factors (OR 1.35; 95% CI 1.07-1.71). Diuretic use was lowest in the Chinese (22%) and Hispanic participants (32%) and was significantly lower in these groups compared with white participants (47%; P < .0001 for both comparisons). Programs to improve hypertension treatment and control should focus on a better understanding of differences in the prevalence of hypertension and hypertension control among minority groups in the United States, especially African Americans, compared with whites, and on techniques to prevent hypertension and improve control in high-risk groups.