(113) Racial disparities in survival among low-income populations with lung, breast, prostate or colorectal cancers across the Southeastern United States

Background: It is well established that race and income levels are social factors that contribute to persistent inequities in cancer care delivery and outcomes, inclusive of breast, prostate, lung and colorectum, the four most common cancers in the United States. However, patterns of cancer disparities within underserved populations—such as those with an annual household income (AHI) of less than $15,000—remain incompletely understood.

Objectives: We sought to evaluate survival among low-income individuals diagnosed with breast, prostate, lung and colorectal cancers in the Southeastern United States.

Methods: Using prospectively collected data from the Southern Community Cohort Study, linkage to state cancer registries and the National Death Index, we identified adults diagnosed with a primary breast, prostate, lung or colorectal cancer. Cox proportional hazards models were used to compare race-specific survival among individuals by AHI.

Results: A total of 5,131 individuals who self-identified as White or Black included in this study were diagnosed with breast (n=1,347), prostate (n=1,367), lung (n=1,569) or colorectal (n=848) cancers. Over half of individuals (56.3%; n=2,889) reported an AHI of less than $15,000 at study enrollment. For all cancer types, individuals with an AHI of less than $15,000 had a significantly higher hazard of death compared with those $15,000+ AHI in adjusted models. Among those reporting an AHI of less than $15,000, Black individuals did not have a significantly higher hazard of death compared with Whites for breast (hazard ratio [HR], 1.14; 95% CI 0.83-1.55), prostate (HR, 1.18; 95% CI, 0.74-1.87) and colorectal (HR, 0.98; 95% CI, 0.71-1.36) cancers in adjusted models. In contrast, Black individuals with lung cancer and an AHI of less than $15,000 had a lower hazard of death compared with Whites after adjustment for age, sex, surgery, stage, smoking history, enrollment years and source (HR, 0.79; 95% CI 0.68-0.92).

Conclusions: Among individuals with an AHI of less than $15,000, racial disparities in survival persisted for lung, but not breast, prostate or colorectal cancers. In low-income populations, race may not consistently be predictive of unmet medical need. Disentangling the interplay of race and income on cancer survival and improving equitable access to high-quality medical services related to cancer care, harbor potential to mitigate inequities and improve clinical outcomes across disease sites.