Socioeconomic and Urban-Rural Disparities in Genome-Matched Treatment Receipt and Survival after Genomic Tumor Testing.

Abstract

Emerging cancer treatments are often most available to socially advantaged individuals. This study examines the relationship of patient educational attainment, income level, and rurality to the receipt of genome-matched treatment (GMT) and overall survival. Survey and clinical data were collected from patients with cancer (n = 1258) enrolled in the Maine Cancer Genomics Initiative. Logistic regression models examined whether receipt of GMT differed by patient education, income, and rurality. Kaplan-Meier curves and Cox regression were conducted to evaluate 12-month mortality. We completed additional exploratory analyses using Kaplan-Meier curves and Cox models stratified by receipt of GMT. Both logistic and Cox regression models were adjusted for age and gender. Educational attainment, income level, and rurality were not associated with GMT receipt. Of 1258 patients, 462 (36.7%) died within 365 days of consent. Mortality risk was associated with lower educational attainment (hazard ratio (HR): 1.30; 95% CI: 1.06 to 1.59; p = .013). No statistically significant differences in mortality risk were observed for income level or rurality. Exploratory models suggest that patients who did not receive GMT with lower educational attainment had higher mortality risk (HR = 1.36, 95% CI: 1.09 to 1.69, p = .006). For patients who did receive GMT, there was no difference in mortality risk between the education groups (HR: 1.01, 95% CI: 0.56 to 1.81, p > .9). While there were no disparities in who received GMT, we found a disparity in mortality associated with education level, which was more pronounced for patients who did not receive GMT. Future research is warranted to investigate the intersectionality of social disadvantage with clinical outcomes to address survival disparities.