Lowering Cardiovascular Disease Risk for African Americans Focus of Study

By Dirk Hoffman

Rebekah Walker, PhD, associate professor of medicine and chief of the Division of Population Health, is principal investigator on a five-year, $3.28 million grant from the National Institute on Minority Health and Health Disparities, part of the National Institutes of Health (NIH).

The study is titled “Cardiovascular Risk Reduction for Adults With Food Insecurity Using Structured Incentives (CVD-FIT).”

Nearly 127 million people in the United States have cardiovascular disease and it is the leading cause of death, both in the U.S. and worldwide.

Food insecurity is associated with increased cardiovascular risk and excess death due to CVD, and while 10.5% of the U.S. population experience food insecurity, over 20% of African Americans experience it, according to Walker.

“Most food insecurity interventions focus on identifying people who are food insecure and referring them to resources, providing food supplementation through a variety of ways such as farmers markets or stockboxes, or providing rebates or grocery store discounts to improve access to food,” Walker says.

“All of these methods focus on food itself, but do not address the underlying driver of food insecurity, which is poverty, or address the long-term health risks that result from food insecurity,” she notes.

The clinical trial will test an intervention that combines three components:

• monthly income supplementation to address the underlying poverty faced by individuals who are food insecure
  
• financial incentives conditional on the purchase of healthy food aimed at increasing the likelihood of food insecure individuals eating a healthier diet
  
• education and skills training specific to reducing CVD risk
  

“Our study aims to change the focus on the singular aspect of increasing food access without accounting for underlying poverty, which is the reason people are food insecure,” Walker says.

“If successful, this intervention will simultaneously address food insecurity and lower CVD risk for individuals at high risk. It will also help to shift the focus away from addressing food insecurity as an issue of food alone, and provide evidence for how to integrate social and medical care to improve health outcomes.”

Walker says her research team has been investigating the role behavioral economics can play in improving health outcomes for adults with diabetes through using financial incentives.

Behavioral economics theorizes that financial incentives provide an extrinsic motivation in the form of a financial reward for behavior change. Provided over time and linked to healthy behaviors, this initial extrinsic motivation can transition to intrinsic motivation to continue engaging in healthy behaviors, she adds.

Income supplementation provides funds to maintain a basic living standard and helps to address material needs, such as housing or nutrition.

“This work has been very promising; however, incentives alone may not allow individuals struggling with food insecurity to change behavior,” Walker says.

Walker says some studies of income supplementation show impacts on lowering food insecurity, but there are few income supplementation studies that target health outcomes.

“We are hypothesizing that we need a combination of income supplementation to address underlying poverty, financial incentives to incentivize behavior change surrounding food purchasing, and education to help support overall behavior change to reduce CVD risk,” she says. “So, our intervention incorporates all three components.”

The researchers will recruit study participants directly from the community and will be enrolling adults 40 years or older, who self-report as African American or Black, screen positive for food insecurity risk, and screen positive for CVD risk.

“There are many risk factors for developing CVD, including high blood pressure, high cholesterol, smoking, type 2 diabetes, and having excess weight or obesity,” Walker says. “Individuals with any of these risk factors will be eligible for this study.”

The researchers will randomize 200 clinical trial participants to receive either the multi-component intervention (monthly income supplementation, weekly financial incentives for healthy food purchase, and CVD risk reduction education) or CVD risk reduction education alone.

“Each participant will be followed for 12 months and will participate in four study visits where we will measure CVD risk indicators and complete questionnaires to capture social and psychosocial factors,” Walker says.

“Following the study, we will compare the two groups to test if the intervention resulted in greater improvement of their 10-year CVD risk score compared to the education and skills training control group,” she adds. “We are also planning to see if the intervention improves quality of life and if it is cost effective.”

Leonard E. Egede, MD, the Charles and Mary Bauer Endowed Professor and Chair of the Department of Medicine, is a co-investigator on the grant. 

His NIH-funded study through the National Institute of Diabetes and Digestive and Kidney Diseases investigating the use of financial incentives to improve diabetes outcomes was one of the drivers of development of the current study. 

Other co-investigators on the grant from the Division of Population Health are:

• Jennifer A. Campbell, PhD, MPH, associate professor of medicine
  
• Obinna Ekwunife, PhD, assistant professor of medicine
  
• Raphael Fraser, PhD, research associate professor of medicine