Diabetic ketoacidosis: clinical characteristics, precipitating factors and outcomes of care.

BACKGROUND: Diabetic ketoacidosis (DKA) is a common and serious complication of diabetes mellitus (DM). OBJECTIVES: To evaluate the clinical characteristics, hospital management and outcomes of patients with DKA. METHODS: We performed a retrospective cohort study of patients hospitalized with DKA during the period 1 January 2003 to 1 January 2010. Three groups were compared: patients with mild DKA, with moderate DKA, and with severe DKA. The primary outcome was in-hospital all-cause mortality. The secondary outcomes were 30 days all-cause mortality, length of hospital stay, and complication rate. RESULTS: The study population comprised 220 patients with DKA. In the mild (78 patients) and moderate (116 patients) groups there was a higher proportion of patients with type 1 DM (75.6%, 79.3%) compared with 57.7% in the severe group (26 patients, P = 0.08). HbA1c levels prior to admission were high in all three groups, without significant difference (10.9 +/- 2.2, 10.7 +/- 1.9, and 10.6 +/- 2.4 respectively, P = 0.9). In all groups the most frequent precipitating factors were related to insulin therapy and infections. The patients with severe DKA had more electrolyte abnormalities (hypokalemia, hypomagnesemia, hypophosphatemia) compared with the mild and moderate forms of the disease. While 72.7% of the entire cohort was hospitalized in the general medical ward, 80.8% of those with severe DKA were admitted to the intensive care unit. The in-hospital mortality rate for the entire cohort was 4.1%, comparable with previous data from experienced centers. Advanced age, mechanical ventilation and bedridden state were independent predictors associated with 30 day mortality: hazard ratio (HR) 1.1, 95% confidence interval (CI) 1.02-1.11; HR 6.8, 95% CI 2.03-23.1; and HR 3.8, 95% CI 1.13-12.7, respectively. CONCLUSIONS: Patients with DKA in our study were generally poorly controlled prior to their admission, as reflected by high HbA1c levels. Type 2 DM is frequently associated with DKA including the severe form of the disease. The most common precipitating factors for the development of DKA were related to insulin therapy and infections. Advanced age, mechanical ventilation and bedridden state wer independent predictors of 30 day mortality.