Incidence of Stomach, Liver, and Colorectal Cancers by Geography and Social Vulnerability Among American Indian and Alaska Native Populations, 2010-2019

Social determinants of health and associated systems, policies, and practices are important drivers of health disparities. American Indian and Alaska Native (AI/AN) populations in the United States have elevated incidence rates of stomach, liver, and colorectal cancers compared with other racial/ethnic groups. In this study, we examined incidence rates of 3 types of gastrointestinal cancer among non-Hispanic AI/AN (NH-AI/AN) and non-Hispanic White (NHW) populations by geographic region and Social Vulnerability Index (SVI) score. Incident cases diagnosed during 2010-2019 were identified from population-based cancer registries linked with the Indian Health Service patient registration databases. Age-adjusted incidence rates (per 100,000 population) for stomach, liver, and colorectal cancers were compared within NH-AI/AN populations and between the NH-AI/AN and NHW populations by SVI score. Rates were higher among NH-AI/AN populations in moderate- and high-SVI-score counties in Alaska, the Southern Plains, and the East than in low-SVI counties. Incidence rates among NH-AI/AN populations were elevated when compared with NHW populations by SVI category. Results indicated that higher social vulnerability may drive elevated cancer incidence among NH-AI/AN populations. Additionally, disparities between NH-AI/AN and NHW populations persist even when accounting for SVI. Exploring social vulnerability can aid in designing more effective interventions to address root causes of cancer disparities among AI/AN populations.