Urban families ameliorate rural genitourinary cancer disparities.

Abstract

25 Background: Previous studies have shown that individuals with cancer who live in rural areas have worse cancer-specific outcomes compared to their urban counterparts. Differences in access to high-quality cancer care and adequate social support may explain some of the observed disparity. Rural patients with relatives in urban areas may have better access to care via an increased ability to navigate the healthcare system than their rural counterparts without relatives in urban areas. In this study, we examine the possibility of a family-based social capital effect on genitourinary cancer survival. We hypothesized that rural patients who have family members living in urban areas have survival outcomes similar to their urban counterparts. Methods: We performed a retrospective cohort analysis of individuals diagnosed with genitourinary cancers, including prostate, bladder, kidney, penile, and testicular cancers. We constructed familial networks using the Utah Population Database (UPDB). Patients were classified as living in either rural or urban areas based on the rural-urban commuting area (RUCA) codes associated with their zip code of residence at the time of cancer diagnosis. Adult first degree relatives (siblings, parents, children) were identified and classified as urban or rural based on the zip code or county of residence at the time of the patients’ diagnosis or, when unavailable, the county or zip code of residence before or after diagnosis. Overall survival (OS) was analyzed using Cox proportional hazards models. Results: We identified 24,746 individuals diagnosed with genitourinary cancer between 1968-2018. Median follow-up was 8.72 years. After adjusting for sex, age, race, cancer type, health improvement index (HII), and Simpson’s diversity index, urban patients had the best OS at 5 and 10 years (reference group). Rural cancer patients without an urban first degree relative had the worst outcomes with OS hazard ratios at five and ten years of 1.4 (CI 1.23-1.58) and 1.4 (CI 1.26-1.55), respectively. Having an urban first degree relative ameliorated much of the urban-rural disparity with five- and ten-year OS hazard ratios of 1.19 (CI 1.07-1.31) and 1.12 (CI 1.03-1.21), respectively. Conclusions: Individuals diagnosed with cancer who live in rural areas have worse survival as compared to their urban counterparts, but this relationship appears to be heavily influenced by the presence or absence of relatives who live in urban areas. Further research is needed to better understand the mechanisms through which having an urban family member may contribute to improved cancer outcomes for rural patients. This may help in the crafting of policies that can reduce urban-rural cancer disparities. Funding: Research reported in this publication was supported by the National Cancer Institute of the National Institutes of Health (K08CA234431 & P30CA042014-31S2). The content does not represent the views of the National Institutes of Health.