Income instability nearly doubles risk of CVD, death in young adults

Unpredictable drops in income in a person’s early 20s through mid-30s have been associated with a nearly twofold increased risk of all-cause death or CVD events, including heart attack, stroke and heart failure.

A study, co-funded by the American Heart Association and National Institutes of Health, considered data from the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, an ongoing research effort tracking 3,937 individuals in Minneapolis, Chicago, Birmingham, Alabama, and Oakland, California. Tali Elfassy, PhD, and colleagues analyzed those patients’ income data over a 15-year period and compared it to their medical records during the same time.

“Income volatility is on the rise and presents a growing public health problem,” Elfassy, an assistant professor at the University of Miami Miller School of Medicine, and coauthors wrote in Circulation Jan. 7. “Because in many epidemiological studies income is measured at a single point in time, the association of long-term income volatility with incident CVD and mortality has not been adequately explored.”

CARDIA participants were all between 23 and 35 years old at the study’s baseline in 1990. Elfassy et al. looked at income data collected until 2005 and then cardiovascular outcomes data from 2005 to 2015. The authors defined income volatility as the percent change in income from one assessment to the next—participants were evaluated five times over the course of 15 years—and income drop as a decrease of 25 percent or more from the last measurement.

Using medical records and death certificates, the researchers found a total of 106 CVD events and 164 deaths occurred in the study population between 2005 and 2015. Higher income volatility was directly linked to more than double the risk of CVD and a 1.9-fold increased risk of all-cause mortality.

According to the study, compared to white men, black participants and women were more likely to experience high income volatility and income drops.

“Income volatility presents a growing public health threat, especially when federal programs, which are meant to help absorb unpredictable income changes, are undergoing continuous changes, and mostly cuts,” Elfassy said in a release. “While this study is observational in nature and certainly not an evaluation of such programs, our results do highlight that large negative changes in income may be detrimental to heart health and may contribute to premature death.”