Covariates

We adjusted for several sociodemographic variables including age, sex, race or ethnicity (non-Hispanic White, non-Hispanic Black, Chinese, or Hispanic), education (categorized as less than high school, high school graduate, some college, and college or more completed), and income (broken into quartiles).

We also adjusted for several CVD risk factors explain associations of chronic stress with endothelial dysfunction, either as mediators or confounders. Waist circumference was measured at the umbilicus to the nearest 1cm. Seated, resting blood pressure was measured 3 times at 2-minute intervals using an automated oscillometric device with appropriate sized cuffs (Dinamap Monitor Pro 100, GE Healthcare). Systolic blood pressure and diastolic blood pressure were modeled continuously based on the average of the final 2 readings. Plasma high-density lipoprotein cholesterol and total cholesterol were measured by the cholesterol-oxidase method and modeled continuously. Use of blood pressure-lowering and any lipid-lowering medication were each self-reported. Cigarette smoking was based on self-report and categorized as current, former, and never. Physical activity was assessed using the MESA Typical Week Physical Activity Survey, adapted from the Cross-Cultural Activity Participation Study.¹⁹ Participants were asked to report the time and frequency spent in 28 different types of physical activities during a typical week in the previous month. Minutes of each activity were multiplied by the appropriate metabolic equivalent level and summed to obtain a composite score. Physical activity was modeled continuously.