Structural racism may play a role in increased cancer mortality rates among racial minorities

Structural racism was associated with increased county-level cancer mortality rates among minority populations compared with whites, according to results presented at the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved, held September 29–October 2, 2023.

"Applying measures that attempt to capture the multiple and compounding ways racism presents in policies, laws, and practices at a population level shows how racism manifests beyond interpersonal interactions to negatively impact cancer outcomes," said presenter Joelle N. Robinson-Oghogho, Ph.D., MPH, a postdoctoral fellow at Johns Hopkins Bloomberg School of Public Health, Department of Health, Behavior and Society. "Studying the impact of structural racism on cancer outcomes allows us to further understand the persistent racial disparities in cancer and broaden our scope of intervention."

Robinson-Oghogho and colleagues explored the association between structural racism and cancer mortality rates in 1,026 U.S. counties and investigated whether this association differed by race among non-Hispanic Black, white, Asian/Pacific Islander, and American Indian and Alaskan Native populations.

The researchers used publicly available data on 2015–2019 cancer mortality rates from the U.S. Cancer Statistics Data Visualization Tool and obtained information on factors associated with cancer mortality rates from the 2019 County Health Rankings and Roadmaps, the U.S. Environmental Protection Agency's 2006–2010 Environmental Quality Index report, and 2015–2019 estimates from the U.S. Census American Community Survey.

The team measured county-level structural racism by applying a previously developed standardized index that takes into account residential segregation, incarceration, employment, economic status/wealth, and education. The county-level structural racism factor scores obtained through this method represent the number of standard deviations that separate the structural racism value for a given county from the mean value for all counties.

After adjusting for environmental quality, adult smoking, obesity, excessive alcohol consumption, health insurance coverage, rates of sexually transmitted infection, mammography screening rates, primary care physician-to-population ratio, rurality, and geographic mobility, higher county structural racism scores were associated with higher rates of cancer mortality: Overall, every standard deviation increase in the score was associated with 3.3 additional cancer deaths per 100,000 people.

Furthermore, the increase was higher among historically minoritized populations compared to white populations. Specifically, for every standard deviation increase in the score, compared to white populations, cancer mortality rates increased by 11.9 deaths per 100,000 people for non-Hispanic Blacks, 4.7 deaths per 100,00 people for Asian/Pacific Islanders, and 17.4 deaths per 100,000 people for American Indian/Alaskan Natives. "This finding demonstrates how racial groups can be differentially impacted by the social characteristics of their environment," said Robinson-Oghogho. "Addressing these disparities will require incorporating processes and tools that tackle structural racism."

The limitations of this study include that the analysis was based on a subset of U.S. counties, which likely limited the number of counties with available data for American Indian/Alaskan Natives and certain other populations.