Rate and Predictors of 30-day Readmission following Diabetic Ketoacidosis in Type 1 Diabetes Mellitus: A US Analysis

Context: Diabetic ketoacidosis (DKA) is a serious endocrine emergency, associated with morbidity and mortality. Readmissions play a significant but sometimes preventable role in healthcare cost burden on the US. Objective: This study aimed to describe rates and characteristics of nonelective 30-day readmission among adult patients with diabetes mellitus type 1 (T1DM) hospitalized for DKA and also identify predictors of readmission. Methods: The study analyzed the 2018 Nationwide Readmission Database. DKA hospitalizations in patients with T1DM were classified using International Classification of Diseases, Tenth Revision, Clinical Modification codes. We utilized chi-squared tests to compare baseline characteristics between readmissions and index hospitalizations. Multivariable Cox regression was employed to identify independent predictors of readmission. Following this, we developed a 30-day readmission risk scoring system based on independent predictors. Results: The 30-day all-cause readmission rate for DKA was 19.4%. A majority of patients (64.8%) had DKA as the principal diagnosis on readmission. Readmitted patients had a significantly higher mean age (35.3 vs 34.9 years, P =.018) and a higher proportion of females (52.8 vs 49.6%, P <.001) than the index admission. Readmission following DKA was associated with higher odds of inpatient mortality (0.69 vs 0.24%, OR 2.84, 95% CI 1.99-4.06, P <.001). Independent predictors of 30-day all-cause readmission included female sex, index hospitalizations with Charlson Comorbidity Index (CCI) score of 3 or greater, and being discharged against medical advice (AMA). Conclusion: The readmission rate for DKA in T1DM patients is high, and most patients have DKA as the principal diagnosis on readmission. A CCI equal to or greater than 3, hypertension, female sex, and being discharged AMA were significant predictors of readmission.