Social inequalities and atherosclerosis. The atherosclerosis risk in communities study.

The cross-sectional associations of social class indicators with coronary heart disease prevalence and subclinical atherosclerosis were investigated among 15,800 persons from four US communities between 1987 and 1989. Among persons without clinical atherosclerotic disease, ultrasound-determined intimal-medial wall thickening of the carotid arteries was used as an indicator of subclinical atherosclerosis. Odds ratios for coronary heart disease prevalence and mean differences in carotid wall thickness were investigated before and after adjustment for cardiovascular risk factors. After adjustment for age and gender, the lowest income category was associated with a threefold increase in coronary heart disease odds compared with the highest category (for whites, odds ratio (OR) = 3.4, 95% confidence interval (CI) 1.8-6.6; for blacks, OR = 3.2, 95% CI 2.2-4.8). Odds ratios increased linearly with decreasing income (p