Relative impact of genetic ancestry and neighborhood socioeconomic status on all-cause mortality in self-identified African Americans

Abstract

Self-identified race/ethnicity is a correlate of both genetic ancestry and socioeconomic factors, both of which may contribute to racial disparities in mortality. Investigators often hold a priori assumptions, rarely made explicit, regarding the relative importance of these factors. We studied 2,239 self-identified African Americans (SIAA) from the Prostate, Lung, Colorectal and Ovarian screening trial enrolled from 1993–1998 and followed prospectively until 2019 or until death, whichever came first. Percent African genetic ancestry was estimated using the GRAF-Pop distance-based method. A neighborhood socioeconomic status (nSES) index was estimated using census tract measures of income, housing, and employment and linked to participant residence in 2012. We used Directed Acyclic Graphs (DAGs) to represent causal models favoring (1) biomedical and (2) social causes of mortality. Hazard ratios were estimated using Cox models adjusted for sociodemographic, behavioral, and neighborhood covariates guided by each DAG. 901 deaths occurred over 40,767 person-years of follow-up. In unadjusted (biomedical) models, a 10% increase in percent African ancestry was associated with a 7% higher rate of all-cause mortality (HR: 1.07, 95% CI: 1.02, 1.12). This effect was attenuated in covariate adjusted (social) models (aHR: 1.01, 95% CI: 0.96, 1.06). Mortality was lower comparing participants in the highest to lowest nSES quintile following adjustment for covariates and ancestry (aHR: 0.74, 95% CI: 0.57, 0.98, Ptrend = 0.017). Higher African ancestry and lower nSES were associated with higher mortality, but African ancestry was not associated with mortality following covariate adjustment. Socioeconomic factors may be more important drivers of mortality in African Americans.

Disparities in the use of colorectal cancer screening in a universally insured population during the COVID‐19 pandemic

“…The 21% reduction in screening encountered in our own data appears consistent with the latter published reports and endorses the external validity of our findings. Similarly, the reduced use of screening among individuals of lower socioeconomic class, Asian, and the Native American population prior to the pandemic is aligned with other reports from this period 6–8,26 …”

“…Similarly, the reduced use of screening among individuals of lower socioeconomic class, Asian, and the Native American population prior to the pandemic is aligned with other reports from this period. [6][7][8]26 Outside of our determinations regarding reduced colorectal screening overall, the most concerning findings are those that indicate persistent disparities in the use of these services among African Americans, Asians, Pacific Islanders, and Native Americans/Alaskans, as well as individuals of lower socioeconomic backgrounds. Worsening disparities among Native Americans/Alaskans, based on socioeconomic status, were also evident in the pandemic period.…”

“…Despite the known efficacy of CRC screening, the rates of individuals undergoing such testing have remained lower than target thresholds, even prior to the healthcare disruptions precipitated by the COVID‐19 pandemic 1,2,4,5 . Disparities were already identified in the pre‐COVID‐19 window among minorities and those from lower socioeconomic strata (SES) 6–8 . These differences in access to screening as well as utilization may have been exacerbated further by disruptions resulting from COVID‐19, including the restricted performance of elective interventions such as colonoscopies 4,5,9–12 .…”

Neighborhood Disadvantage, African Genetic Ancestry, Cancer Subtype, and Mortality Among Breast Cancer Survivors

“…They found that African genetic ancestry was correlated with TNBC in unadjusted models, but this association attenuated to the null following adjustment for nSES. In a secondary analysis of 2239 Black men and women in the Prostate, Lung, Colorectal, and Ovarian cancer screening trial, associations between African genetic ancestry, nSES, and overall mortality found that although African ancestry was initially associated with higher all-cause mortality, this association attenuated following adjustment for lifestyles and comorbidities . Similarly, no associations were observed between African ancestry and cancer-related mortality.…”

“…While available evidence suggests both genetic and environmental factors may explain excess mortality in Black women, few studies have incorporated them in their design and analysis . Failure to account for both genetic and nSES factors may lead to overestimates of their relative importance . To address these gaps, we examined joint associations of African ancestry (representing genetic influences) and nSES (representing environmental influences) on tumor aggressiveness and mortality in a large, population-based cohort of Black female breast cancer survivors.…”