Incidence and long-term outcomes of adult patients with diabetic ketoacidosis admitted to intensive care: A retrospective cohort study.

AIMS: Diabetic ketoacidosis is a life-threatening but avoidable complication of diabetes mellitus often managed in intensive care units. The risk of emergency hospital readmission in patients surviving an intensive care unit episode of diabetic ketoacidosis is unknown. We aimed to report the cumulative incidence of emergency hospital readmission and costs in all patients surviving an intensive care unit episode of diabetic ketoacidosis in Scotland.
METHODS: We used a national six-year cohort of survivors of first diabetic ketoacidosis admissions to Scottish intensive care units (1 January 2005-31 December 2010) identified in the Scottish Intensive Care Society Audit Group registry linked to acute hospital and death records (follow-up censored 31 December 2010). Diabetic ketoacidosis-related emergency readmissions were identified using International Classification of Disease-10 codes.
RESULTS: During the study period, 386 patients were admitted to intensive care units in Scotland with diabetic ketoacidosis (admission rate 1.5/100,000 Scottish population). Median age was 44 (IQR 29-56); 51% male; 55% required no organ support on admission. Mortality after intensive care unit admission was 8% at 30 days, 18% at one year, and 35% at five years. A total of 349 patients survived their first intensive care unit diabetic ketoacidosis admission [mean (SD) age 42.5 (18.1) years; 50.4% women; 46.1% required ≥1 organ support]. Following hospital discharge, cumulative incidence of 90-day, one-year, and five-year diabetic ketoacidosis readmission (all-cause readmission) was 13.8% (31.8%), 29.7% (58.9%) and 46.4% (82.6%). DISCUSSION: Diabetic ketoacidosis in patients requiring intensive care unit admission is associated with high risk of long-term mortality and high hospital costs. An understanding of the precipitating causes of diabetic ketoacidosis in patients admitted to intensive care units may allow patients who are at high risk to be targeted, potentially reducing future morbidity and the substantial burden that diabetic ketoacidosis currently places on the healthcare system.