COUNTY MEDIAN FAMILY INCOME AS PROGNOSTIC FACTOR IN NON-SMALL-CELL LUNG CANCER WITH BRAIN METASTASES AT PRESENTATION: A POPULATION-BASED STUDY

Abstract INTRODUCTION The purpose of this study was to characterize the impact of household income disparities in the survival of patients with non-small cell lung cancer (NSCLC) presenting with brain metastasis on a population-based level. METHODS This is a population-based cohort study using the SEER database from 2010-2016 including 15,808 NSCLC patients presenting with brain metastasis. Two-tailed log-rank test was used to compare overall survival between groups and association with survival was quantified using hazard ratios (HR) with 95 % confidence intervals (CI) assessed with univariate and multivariate Cox proportional hazard models. RESULTS Patients living in low-income counties had a median survival of 4 months when compared to 5 months for patients living in high-income counties respectively (p< 0.0001). Patients living in first and second bottom quartiles had a median survival of 4 months and 5 months and 6 months for the third and fourth top quartiles, respectively (p< 0.0001). The 1-, 2- and 5-year survival rates for living in the lower household income quartile were 21, 10 and 3% respectively, for the second quartile 24, 10 and 3%; for the third quartile 28, 14 and 4% and for the top fourth quartile 31, 17 and 4% respectively. Multivariate cox proportional hazard analysis adjusted for age, gender, race, hispanic ethnicity, marital status, insurance status, percentage of high school education in the patient’s county, histology, presence of lung metastasis, bone metastasis, liver metastasis, radiation received, surgery performed, and chemotherapy received showed that living in higher quartile household income county is associated with decrease mortality risk (p < 0.0001) HR 0.87 95% CI (0.82-92). CONCLUSION This population-based study suggests that living in higher median household income counties is associated with increased survival time and reduced risk of mortality for patients with NSCLC who have brain metastases present at diagnosis, independent of other factors.