Racial and Ethnic Disparities in Type 2 Diabetes Complications and In-Hospital Mortality in the United States: A Retrospective Cohort Study

Objectives: To describe the association of race with type 2 diabetes complications and determine if differences in rates of complications exist between racial/ethnic groups of adult type 2 diabetes patients in the United States. Additionally, we model the odds of in-hospital patient mortality across racial/ethnic groups. Methods: A retrospective cohort study was conducted using data from the 2018 National Inpatient Sample of Healthcare Cost and Utilization Project, including 97,314 unweighted and 486,500 weighted adults with type 2 diabetes. Chi-square analysis was used to determine the association of race with diabetes complications, along with z-tests to determine the differences in complication rates of 11 different complications between racial/ethnic groups and binary logistic regression to model in-hospital mortality. Results: Our analysis revealed significant racial/ethnic disparities in both complication rates and odds of in-hospital mortality. Whites had the lowest rate of complications overall, except for arthropathy/oral complications (18.8%) and foot/skin ulcers (18.2%), while Black/African Americans had the highest rates of hyperosmolarity (7.3%), ketoacidosis (21.2%), neurological complications (8.9%), and hyperglycemia (13.4%). Asian/Pacific Islanders had the highest rates of hypoglycemia (17.6%) as well as kidney (7.2%) and ophthalmic (0.3%) complications, and Hispanics the highest rates of circulatory complications (19.0%). Hispanic ethnicity was associated with 10.6% reduced odds of in-hospital mortality, and Asian/Pacific Islanders and Other races had increased odds of mortality by 25.2% and 27.0%, respectively. Notably, neurological (OR = 0.278, 95% CI: 0.111, 0.702) complications and hyperglycemia (OR = 0.304, 95% CI: 0.124, 0.749) were associated with a reduction in mortality odds by 62.2% and 69.6%, possibly reflecting the study's focus on in-hospital rather than all-cause or 30-day mortality. Conclusions: We demonstrated disparities in both rates of type 2 diabetes complications and odds of mortality between different racial/ethnic groups. These results lay groundwork for future research into the root causes of these disparities and highlight the importance of targeting interventions and equitable case for those most at risk.