Disparities in patient and system factors explain racial/ethnic disparities in delayed time to treatment in muscle invasive bladder cancer.

Abstract

Treatment delays in muscle invasive bladder cancer (MIBC) have been shown to be associated with worse outcomes. While every attempt is made to provide adequate treatment expeditiously, Black and Hispanic patients often experience delays at a higher rate than their White counterparts. This study aims to quantify the mechanisms that contribute to this disparity in treatment delay. Retrospective analysis of clinical T-stages II-IVa MIBC patients who underwent surgical resection from 2004 to 2017 in the National Cancer Database. A causal inference mediation analysis using the counterfactual framework was implemented to estimate the extent to which racial/ethnic disparities in patient and system factors explain the racial/ethnic disparities in time to treatment. Mediators included income, education, comorbidities, insurance, and hospital type. Among 22,864 patients who met inclusion criteria, 7%, 3%, 2% were of Black, Hispanic, and Other race/ethnicity, respectively. In multivariable models, compared to White patients, Black, and Hispanic patients were associated with 26% (odds ratio = 1.26, 95% confidence interval = 1.12-1.42) and 29% (odds ratio = 1.29, 95% confidence interval = 1.07-1.55) increased odds of having a treatment delay relative to White patients. Mediation analyses suggested that 49% and 26% the treatment delay among Black and Hispanic patients, respectively, could be removed if an intervention equalized the distribution of academic treatment, education, and insurance status to that of White patients. Treatment at an academic hospital and education were the mediators that explained the largest portion of the racial/ethnic disparity in treatment delay. Black and Hispanic MIBC patients experience treatment delays when compared to White patients. Intervening upon patient and system factors could reduce substantial treatment delays. Future research is needed to identify other causes of disparities in treatment delays and may help population health initiatives to address racial/ethnic disparities in clinical settings.