Pre- and in-hospital lactate ratio as a predictor of mortality in severe diabetic ketoacidosis: a multicenter prospective cohort study

OBJECTIVE: Lactate kinetics between prehospital and in-hospital measurements have been associated with prognosis in acute conditions. This study aimed to evaluate the prognostic value of the prehospital-to-hospital lactate ratio in patients with severe diabetic ketoacidosis (DKA). METHODS: This was a prospective, multicenter cohort study including adults attended by emergency medical services (EMS) with a diagnosis of severe DKA or hyperosmolar hyperglycemic state. The lactate ratio was calculated by dividing the initial prehospital point-of-care lactate value by the in-hospital measurement. The optimal cutoff point was identified via locally weighted scatter plot smoother curve analysis. Survival was analyzed using Kaplan-Meier curves and Cox regression, adjusted for age, age-adjusted Charlson comorbidity index (ACCi), precipitating factor, and prehospital Glasgow Coma Scale (GCS) score. RESULTS: A total of 128 patients were included (median age 71 years [IQR 58.5-80], 47.7 % female). The median ACCi was 7 (IQR 5-9), and in-hospital mortality was 34.4 %. Patients were stratified by lactate ratio