The association of admission blood glucose level with the clinical picture and prognosis in cardiogenic shock - Results from the CardShock Study

Background: Critically ill patients often present with hyperglycemia, regardless of previous history of diabetes mellitus (DM). Hyperglycemia has been associated with adverse outcome in acute myocardial infarction and acute heart failure. We investigated the association of admission blood glucose level with the clinical picture and short-term mortality in cardiogenic shock (CS).

Methods: Consecutively enrolled CS patients were divided into five categories according to plasma glucose level at the time of enrolment: hypoglycemia (glucose <4.0mmol/L), normoglycemia (4.0-7.9mmol/L), mild (8.0-11.9mmol/L), moderate (12.0-15.9mmol/L), and severe (≥16.0mmol/L) hyperglycemia. Clinical presentation, biochemistry, and short-term mortality were compared between the groups.

Results: Plasma glucose level of 211 CS patients was recorded. Glucose levels were distributed equally between normoglycemia (26% of patients), mild (27%), moderate (19%) and severe (25%) hyperglycemia, while hypoglycemia (2%) was rare. Severe hyperglycemia was associated with higher blood leukocyte count (17.3 (5.8) E9/L), higher lactate level (4.4 (3.3-8.4) mmol/L) and lower arterial pH (7.23 (0.14)) compared with normoglycemia or mild to moderate hyperglycemia (p<0.001 for all). In-hospital mortality was highest among hypoglycemic (60%) and severely hyperglycemic (56%) patients, compared with 22% in normoglycemic group (p<0.01). Severe hyperglycemia was an independent predictor of in-hospital mortality (OR 3.7, 95% CI 1.19-11.7, p=0.02), when adjusted for age, gender, LVEF, lactate, and DM.

Conclusions: Admission blood glucose level has prognostic significance in CS. Mortality is highest among patients with severe hyperglycemia or hypoglycemia. Severe hyperglycemia is independently associated with high in-hospital mortality in CS. It is also associated with biomarkers of systemic hypoperfusion and stress response.