Hyperglycaemia at admission in acute coronary syndrome patients: prognostic value in diabetics and non-diabetics

Objective To evaluate the impact of admission glycaemia on short-term and long-term prognosis in diabetic and non-diabetic patients admitted for acute coronary syndromes (ACS), and to identify the independent predictors of post-ACS mortality in this population. Methods This study included 1149 consecutive patients admitted to a single coronary care unit for ACS between May 2004 and December 2006. Our population was divided into four groups according to the quartiles of glycaemia at admission [Q1 > 5.77 mmol/l, Q2 (5.77–7.0) mmol/l, Q3 (7.0–9.22) mmol/l and Q4 ≥ 9.22 mmol/l]. Diabetic (n = 396) and non-diabetic (n = 753) subgroups were then separately analysed. Results Hyperglycaemia at admission was associated with worse cardiovascular risk profile, high levels of necrosis and inflammation biomarkers and low left ventricle ejection fraction. Considering overall population, in-hospital, 30-day and 3-year mortalities were higher in more elevated glycaemia quartiles. In diabetic patients, there were no significant differences in mortality among glycaemia quartiles; however, in non-diabetic group higher admission glucose levels were associated with successively higher in-hospital and 3-year mortalities. After multivariate regression analysis, glycaemia at admission ≥ 5.77 mmol/l, age ≥ 72 years, Killip class [1 and troponin I ≥ 6.0 ng/ml were independent predictors of in-hospital mortality. Conclusion This study suggests that, in a broad ACS population, hyperglycaemia at admission is a short-term and long-term bad prognosis marker, particularly in non-diabetic patients, being a strong independent predictor of in-hospital mortality.