Exploring the Intersection Between Persistent Poverty and Rurality Status for Advanced Stage Diagnosis of Breast Cancer using the Surveillance, Epidemiology, and End Results (SEER) Program

Abstract

Persistent poverty has been associated with disparities in cancer outcomes. Prior studies have described these disparities as most important for rural areas. This study seeks to provide insight into the roles of persistent poverty and rurality status, on receiving an advanced stage breast cancer diagnosis (stage II, III, and IV) relative to stage I. This cross-sectional study utilized the SEER database, including female individuals diagnosed from 2010 to 2020. Persistent poverty was defined as an area that has consistently maintained a poverty rate of 20% or more for a period of at least 30 years. Urban rural status was defined based on the percentage of people living in a non-urban area. Adjusted multinomial logistic regression models were used to estimate the likelihood of receiving an advanced stage diagnosis associated with persistent poverty and urban-rural status. Stratified analysis and a likelihood ratio test comparing models with and without interaction terms were used to assess effect modification by urban-rural status. A total of 492,050 female individuals were included in this study of which 6.9% lived in persistent poverty areas. Individuals residing in persistent poverty areas had higher risks of presenting with a more advanced stage at diagnosis. The risks were also higher for individuals residing in mostly rural and all rural areas. Stratified analysis by urban-rural classification revealed that the effect of persistent poverty was greater among all urban and mostly urban areas. Effect modification was found by urban-rural classification (p=0.002). This study found that persistent poverty and urban-rural status is associated with advanced breast cancer stage at diagnosis. Additionally, we found that the effect of persistent poverty is modified by urban-rural classifications.