Abstract C138: Rural realities: Higher mortality in nonelective cancer surgeries and contributing factors
Authors: Torres Crisanto M. , Davis Elizabeth S , Ng Sing Chau , Kenzik Kelly M. 
Published: September 2024

Abstract
Background Rural communities constitute a populace marked by various social challenges influencing health outcomes, with nonelective cancer surgery often serving as an indicator of inadequate healthcare access. This study aims to determine the association between mortality and rurality in patients undergoing nonelective cancer-specific surgery. Additionally, we examine how patient and county-level factors contribute to mortality differences across rural and metropolitan areas. We hypothesize that rural patients experience worse mortality outcomes than metropolitan patients, influenced by race and social determinants. Methods A retrospective study of adult patients captured in the SEER-Medicare data between January 2008 and December 2015. Patients with an incident cancer of the stomach, liver, pancreas, gallbladder, or other biliary origin and who underwent a nonelective cancer-specific surgery were included. The primary outcome was 90-day mortality across the urban-rural continuum categorized as metropolitan (metro), micropolitan (micro), or small town or rural (rural) derived from the 2013 US Department of Agriculture’s Rural-Urban Continuum Codes. We used a multivariable mixed effects model to assess differences in 90-day mortality across the urban-rural continuum while accounting for county-level clustering. The model included age, sex, Elixhauser Comorbidity Index, cancer sites, cancer stage, race, social vulnerability index [SVI], teaching status, and bed size. A nonlinear effect decomposition analysis evaluated the influence of demographic and clinical characteristics on the mortality difference between metropolitan and non-metropolitan residents. ResultsIn total, 2,196 underwent nonelective surgery; metro 1,952 (89%), micro 156 (7%), and rural 88 (4%). The incidence of 90-day mortality was similar across the urban-rural continuum: metro (22%), micro (21%), and rural (25%); p= 0.77. Rural residents had 2.06 higher adjusted odds of 90-day mortality (aOR, 2.06; 95% CI, 1.02-4.14) compared to metropolitan residents. However, there was no difference in the aOR of 90-day mortality between micropolitan (aOR, 0.77; 95% CI, 0.44-1.33) and metropolitan residents. The effect decomposition demonstrated that the mortality difference between metro and non-metro residents was influenced mainly by race (22%), high SVI (8%), and anatomical cancer site (11%). Conclusion Despite the comparable likelihood of receiving nonelective surgery across the urban-rural continuum, rural patients face a distinct disadvantage in postoperative survival. The significant contribution of factors such as race and socioeconomic vulnerability to the observed mortality differences underscores the complexity of healthcare disparities in rural areas. This study highlights the need for policymakers and healthcare providers to address the systemic inequities faced by rural populations. Enhancing access to quality healthcare, improving socioeconomic conditions, and addressing racial disparities should be prioritized to reduce the mortality gap.
Citation Format: Crisanto M. Torres, Elizabeth S Davis, Sing Chau Ng, Kelly M. Kenzik. Rural realities: Higher mortality in nonelective cancer surgeries and contributing factors [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C138.