Food deserts linked to poor CV outcomes

Living in food deserts—residential areas with low net income and poor access to healthy food—was independently linked to adverse outcomes in patients with coronary artery disease in a study of nearly 5,000 subjects, researchers reported Feb. 11 in the Journal of the American Heart Association.

The study isn’t lead author Heval M. Kelli, MD et al.’s first rodeo—in a report published in Circulation: Cardiovascular Quality and Outcomes in late 2017, the team noted a higher prevalence of hypertension and smoking and increased overall body mass index, fasting glucose and 10-year CVD risk in individuals who lived in food deserts compared to those who didn’t. But the authors said that study, based in the Atlanta metropolitan area, was small-scale and required follow-up.

“Despite these cross-sectional findings, no study has yet directly examined the association between living in a food desert and incident cardiovascular outcomes in a longitudinal study, which would be essential in establishing the causal relationship between food deserts and CVD,” Kelli and co-authors wrote in JAHA. “Furthermore, given the heterogeneity in the definitions of ‘food desert,’ an in-depth examination of what aspects of food deserts drive adverse CV outcomes will also be crucial to address and elucidate the mechanistic pathways from living in food deserts to cardiovascular outcomes and to help design effective policies.”

Kelli, a cardiology fellow at Emory University School of Medicine, and his team enrolled 4,944 subjects from the Emory Cardiovascular Biobank for their study. All patients were undergoing cardiac catheterization at the time and were prospectively followed for around three years for a primary endpoint of MI or death.

The researchers referred to the U.S. Department of Agriculture’s definition of food desert for their work: “Parts of the country vapid of fresh fruit, vegetables and other healthful whole foods, usually found in impoverished areas.” They determined 981 individuals in their study population—20 percent of the pool—were living in areas that met those criteria.

Individuals living in food deserts had a 44 percent higher adjusted risk of MI than those living in non-food deserts, the authors reported. In multivariate analyses that considered both food access and and area income, only living in a lower-income area was associated with a higher adjusted risk of MI or death (40 percent and 18 percent higher, respectively).

“Access to healthy food may be overridden by income and the ability to actually purchase healthy food regardless of whether there is local access to healthy food options,” Kelli et al. wrote. “Among those living in high-income areas, whether living in areas with poor or adequate access did not result in any significant difference in the risk of adverse outcomes.

“Therefore, access to healthy food by itself may not significantly contribute to improved cardiovascular outcomes, and the relative cost of higher-quality food rather than access may be a major barrier to healthy lifestyle and choices.”

The authors said that as neighborhood poverty levels continue to grow, fresh markets are being replaced with convenience stores and fast-food joints, which don’t exactly promote optimal heart health. They also said other characteristics of low-income areas, like social deprivation, lack of cohesion, decreased access to recreational activities, lack of public spaces and safety issues could explain some of their results, but they didn’t study those individual variables.

Overall, the team concluded that while easy access to healthy food is definitely a contributor to good heart health, their findings seemed to be driven more by income than anything else.

“It appears that these neighborhood attributes are correlated with area income, which can be the driver for adverse health outcomes, as demonstrated in our analysis,” they said. “Thus, simply providing interventions and resources focused on providing access to healthy food alone may not be enough to overcome disease risk, especially as it relates to cardiovascular outcomes.”