Socioeconomic status and health: education and income are independent and joint predictors of ambulatory blood pressure.

Epidemiological research suggests that different indicators of socioeconomic status (SES) such as income and education may have independent and/or interactive effects on health outcomes. In this study, we examined both simple and more complex associations (i.e., interactions) between different indicators of SES and ambulatory blood pressure (ABP) during daily life. Our sample consisted of 94 married couples who completed a one-day ABP protocol. Both income and education were independently related to systolic blood pressure and only income was significantly related to diastolic blood pressure. There were also statistical interactions such that individuals with high levels of both income and education evidenced the lowest ABP. Gender moderated these findings. Three-way interactions revealed that, in general, women appear to benefit from either indicator of SES, whereas men appear to benefit more from income. The findings are consistent with epidemiological research and suggest one important physiological mechanism by which income and education may have independent and interactive effects on health.