Influence of Race, Insurance, Rurality, and Socioeconomic Status on Equity of Lung and Colorectal Cancer Care.

Background: This study evaluated the influence that social determinants of health had on stage at diagnosis and receipt of cancer-directed surgery for patients with lung and colorectal cancer in the North Carolina Central Cancer Registry (2010-2015).

Methods: This study examined non-Hispanic uninsured or privately-insured patients 18 to 64 years of age. Multivariable logistic regression models, including two-way interaction terms, assessed the influence of race, insurance status, rurality, and Social Deprivation Index on stage at diagnosis and receipt of surgery.

Results: 6574 lung cancer patients and 5355 colorectal cancer patients were included. Among the lung cancer patients, the uninsured patients had higher odds of having stage IV disease (odds ratio [OR] = 1.46; 95 % confidence interval [CI] = 1.22-1.76) and lower odds of receiving surgery (OR = 0.48; 95 % CI = 0.34-0.69) than the privately-insured patients. Among the colorectal cancer patients, uninsured status was associated with higher odds of stage IV disease (OR = 1.53; 95 % CI = 1.17-2.00) than privately-insured status. A significant insurance status and rurality interaction (p = 0.03) was found in the colorectal model for receipt of surgery. In the privately-insured group, non-Hispanic Black and rural patients had lower odds of receiving colorectal surgery (OR = 0.69; 95 % CI = 0.50-0.94 and OR = 0.68; 95 % CI = 0.52-0.89; respectively) than their non-Hispanic White and urban counterparts.

Conclusions: After controlling for confounding and evaluation of interactions between patient-, community-, and geographic-level factors, uninsured status remained the strongest driver of patients' presentation with late-stage lung and colorectal cancer. As policy and care delivery transformation targets uninsured and vulnerable populations, explicit recognition, and measurement of intersectionality should be considered.