Background: Low income is associated with CVD, although causality remains debated because low income is also associated with depression and negative health behaviors, which can be associated with CVD. For more robust causal inference, changes in income and their association with CVD must be observed.
Study design: Prospective observational cohort study.
Setting: Four U.S. urban centers – Jackson, Miss.; suburbs of Minneapolis; Washington County, Md.; and Forsyth County, N.C.
Synopsis: Among a large cohort of community-dwelling middle-aged adults, this study showed that negative income changes are associated with an increased incidence of CVD. Among 8,989 patients recruited from the four urban centers above, 10% experienced an income drop, 70% did not have a change in income, and 20% experienced an income increase over the first 6 years of the study. Patients were followed for a mean of 17 years, and those who experienced an income drop were found to have a 17% higher risk of incident CVD, whereas those who experienced an income increase had a 14% lower risk of CVD.
The study was limited by difficulties classifying income and its changes; the complicated nature of income, its relationship with other socioeconomic factors, and causation inferences; and the relatively short span over which income was monitored.
Bottom line: Income decrease is associated with an increased risk of incident CVD.
Citation: Wang S et al. Longitudinal associations between income changes and incident cardiovascular disease, the atherosclerosis risk in communities study..
Dr. Rupp is a hospitalist and clinical instructor of medicine at the University of Utah, Salt Lake City.