National-Level Outcomes of Diabetic Ketoacidosis with and without Coma: A Retrospective Analysis of 2.3 Million U.S. Hospitalizations

Background: Diabetic ketoacidosis (DKA) remains a significant complication of diabetes associated with substantial morbidity and mortality. We aimed to evaluate clinical outcomes among patients with DKA, both with and without coma, using a nationally representative database and to identify associated factors. Methods: We analyzed 2,381,619 DKA hospitalizations from the National Inpatient Sample (2016-2022), comparing outcomes between patients with (n=47,355, 1.99%) and without coma (n=2,334,264, 98.01%). Primary outcomes included length of stay (LOS), in-hospital mortality, and total hospital charges. Multivariable regression models adjusted for demographic, clinical, and hospital-level factors. Results: Patients with DKA-related coma had significantly worse outcomes: longer LOS (8.65 vs. 4.91 days), higher mortality (16.36% vs. 3.12%), and higher hospital charges ($119,080 vs. $61,240) compared to non-comatose patients. After adjustment, coma remained strongly associated with adverse outcomes (an additional 3.23 days of LOS, 5.38-fold higher mortality odds, $51,060 higher charges). Age >65 years, Type 2 diabetes, Asian/Pacific Islander race, and treatment at urban teaching hospitals were independently associated with worse outcomes. Female gender was associated with slightly better outcomes across all measures, with a significant interaction between gender and coma status. Conclusion: Consciousness level is among the strongest independent predictors of adverse DKA outcomes. Age, diabetes type, race/ethnicity, and hospital characteristics also significantly impact mortality, length of stay, and hospital charges. These factors should be considered in the clinical management of DKA and hospital resource planning.