Prognostic Value of Admission Blood Glucose Level in Critically Ill Patients Admitted to Cardiac Intensive Care Unit according to the Presence or Absence of Diabetes Mellitus

BACKGROUND: Admission blood glucose (BG) level is a predictor of mortality in critically ill patients with various conditions. However, limited data are available regarding this relationship in critically ill patients with cardiovascular diseases according to diabetic status. METHODS: A total of 1,780 patients (595 with diabetes) who were admitted to cardiac intensive care unit (CICU) were enrolled from a single center registry. Admission BG level was defined as maximal serum glucose level within 24 hours of admission. Patients were divided by admission BG level: group 1 (< 7.8 mmol/L), group 2 (7.8–10.9 mmol/L), group 3 (11.0–16.5 mmol/L), and group 4 (≥ 16.6 mmol/L). RESULTS: A total of 105 patients died in CICU (62 non-diabetic patients [5.2%] and 43 diabetic patients [7.9%]; P = 0.105). The CICU mortality rate increased with admission BG level (1.7%, 4.8%, 10.3%, and 18.8% from group 1 to group 4, respectively; P < 0.001). On multivariable analysis, hypertension, mechanical ventilator, continuous renal replacement therapy, acute physiology and chronic health evaluation II (APACHE II) score, and admission BG level significantly influenced CICU mortality in non-diabetic patients (group 1 vs. group 3: hazard ratio [HR], 3.31; 95% confidence interval [CI], 1.47–7.44; P = 0.004; group 1 vs. group 4: HR, 6.56; 95% CI, 2.76–15.58; P < 0.001). However, in diabetic patients, continuous renal replacement therapy and APACHE II score influenced CICU mortality but not admission BG level. CONCLUSION: Admission BG level was associated with increased CICU mortality in critically ill, non-diabetic patients admitted to CICU but not in diabetic patients.