The future of federally funded research at Harvard Medical School — supported by taxpayers and done in service to humanity — remains uncertain. Learn more.
Higher socioeconomic status, which typically includes higher income and more education, has been linked to better health outcomes. But according to a new study from researchers at Harvard Medical School, these associations are not uniform across racial and ethnic subgroups in the United States — with similar increases in socioeconomic status, some groups saw a much more significant reduction in risk of obesity and diabetes than others.
Socioeconomic status is increasingly being incorporated into tools used to predict health risks and assist doctors in treatment recommendations. However, a risk calculator is only as reliable as its inputs. The findings, published July 8 in PLOS One, show that socioeconomic factors don’t operate uniformly across the population, so a tool that assumes they do will be more accurate for some patients than others.
A one-size-fits-all approach has the potential to widen racial health gaps rather than close them.
The researchers recommend that studies investigating links between socioeconomic status and disease risk account for possible differences between communities and avoid treating the population like a monolith. There’s no agreed-upon standard for how health researchers measure socioeconomic status and the results show that those measurement choices can change the conclusion. Risk prediction requires separating income from education and testing whether effects hold across different groups, the researchers said.
“If we don’t have a good understanding of how these factors impact health, or if we ignore differences across communities, these calculators may lead to worsening health disparities,” said first author Sara Cromer, HMS assistant professor of medicine at Massachusetts General Hospital.
Analyzing data from two large cohort studies — the CDC National Health and Nutrition Examination Survey and the All of Us Study — with over 300,000 U.S. participants, the researchers found that higher education and income were clearly linked with lower rates of type 2 diabetes and obesity for non-Hispanic white Americans and Asian Americans.
But for Black, Hispanic, and other minority groups, higher socioeconomic status had a much weaker effect on health. Strikingly, Black Americans with college degrees had diabetes rates similar to or higher than white Americans who never finished high school. Higher socioeconomic status also had little impact on obesity for these groups, and for some was even associated with worse outcomes.
Although efforts to improve socioeconomic barriers are critical, the work supports prior evidence that improving socioeconomic status alone is not enough to overcome racial and ethnic health disparities in the United States, which arise from a multitude of factors including the direct and indirect effects of structural racism, the researchers said.
“Health disparities run deeper than socioeconomic differences alone, and the way we ascertain it matters,” said senior author Chirag Patel, associate professor of biomedical informatics in the Blavatnik Institute at HMS. “These findings establish a new standard for how researchers should measure, analyze, and report socioeconomic data to capture true health disparities.”
Authorship, funding, disclosures
Additional authors include Julie E. Gervis and Sherri-Ann M. Burnett-Bowie.
This work was supported by the American Diabetes Association (grant 7-21-JDFM-005) and the National Institutes of Health (grants R01ES032470 and R01DK137993).
Cromer has a close family member employed by a Johnson & Johnson company and has served on advisory boards for Alexion Pharmaceuticals, Wolters Kluwer, and Patient Square Capital. Burnett-Bowie serves on a clinical advisory board for Upliv Health.
