Mediating Factors Between Race and Time to Treatment in Colorectal Cancer

BACKGROUND: Previous disparities research has demonstrated that underrepresented racial minority patients have worse colorectal cancer outcomes and that they experience unnecessary delays in time to treatment. These delays may explain worse colorectal cancer outcomes for minority patients and serve as a marker of inequalities in our healthcare system. OBJECTIVE: This study aims to quantify the mechanisms that contribute to this disparity in treatment delay. DESIGN: This is a retrospective analysis of colorectal cancer patients who underwent elective resection from 2004 to 2017. A causal inference mediation analysis using the counterfactual framework was utilized to estimate the extent to which racial disparities among patient factors explain the racial disparities in time to treatment. Mediators included income, education, comorbidities, insurance, and hospital type. SETTINGS: This study was conducted at hospitals participating in the National Cancer Database. PATIENTS: Stage I-III colorectal cancer patients, >= 18 years old, who underwent elective resection from 2004 through 2017 were included. MAIN OUTCOMES MEASURES: The primary measures were indirect effects of mediators between race and delayed time to treatment. RESULTS: Of the 504,405 patients (370,051 colon and 134,354 rectal), 10%, 5%, and 4% were black, Hispanic, and other. In multivariable models, compared to white patients, these patients had 25%, 27%, and 17% greater odds of delayed treatment. Mediation analyses suggested that 43%, 20%, and 31% of the treatment delay among them could be removed if an intervention equalized income, education, comorbidities, insurance, and hospital type to that of white patients. Treatment at an academic hospital explained 15% to 32% of the racial disparity and was the most potent mediator. LIMITATIONS: This study was limited by its retrospective design and failure to capture all meaningful mediators. CONCLUSIONS: Black, Hispanic, and other colorectal cancer patients experience treatment delays when compared to white patients. Equalization of the mediators used in this study could reduce treatment delays by 20% to 43% depending on the racial/ethnic group. Future research should identify other causes of racial disparities in treatment delay and intervene accordingly. See Video Abstract at http://links. lww. com/DCR/B871.

Automated summary

This study found that there are racial disparities in treatment delay among colorectal cancer patients, with minority patients experiencing longer treatment times. Income, education, comorbidities, insurance, and hospital type were important factors contributing to these disparities. Treatment delays could be significantly reduced if these factors were equalized to that of white patients.