Relationship of socioeconomic markers to daily life ischemia and blood pressure reactivity in coronary artery disease patients

Background: Socioeconomic status (SES) is an important predictor of clinical outcomes in patients with coronary artery disease (CAD). Purpose: We hypothesized that a selected sample of low SES cardiac patients would display heightened cardiovascular stress responses in the laboratory and increased daily life ischemia compared to otherwise comparable higher SES patients. Methods: Eighty-Two patients (M age = 61.8 ± 9.4 years; 71 men, 11 women) with a known history of CAD engaged in a stressful mental arithmetic task while blood pressure (BP) measures were collected. Myocardial ischemia was subsequently assessed via 48-hr ambulatory electrocardiographic monitoring in a subgroup of 51 patients. SES was defined by participants' residential block groups, which were linked to Census Bureau data about their neighborhood, including per capita income, percentage of the population below poverty, educational level, as well as self-report of number of years of education. Results: Contrary to expectation, high SES participants in the study displayed higher diastolic BP (p < .01) and systolic BP (p < .001) responses to mental stress in the laboratory. Conclusions: Participants with daily life ischemia came from wealthier neighborhoods using indexes of poverty (p < .01), income (p < .02), and education (p < .04) compared to patients without ambulatory ischemia. This relationship was not accounted for by age, sex, race, body mass index, marital status, or measures of disease severity.