The magnitude of the variation in glycemia: a new parameter for risk assessment in acute coronary syndrome?

INTRODUCTION AND OBJECTIVES The aim was to evaluate the relationship between the magnitude of the variation in the level of glycemia during hospitalization and in-hospital and long-term mortality and postdischarge endpoints in two groups of patients with acute coronary syndrome: those with and those without a previous diagnosis of diabetes. METHODS The study included 1210 patients admitted for acute coronary syndrome between May 2004 and July 2007. The study population was divided in two subgroups: patients with a previous diagnosis of diabetes (n=386) and nondiabetics (n=824). Each subgroup was further divided into four smaller groups according to the quartile of glycemia variation: diabetics (Q1: <46 mg/dl; Q2: 46-88 mg/dl; Q3: 88-164 mg/dl; Q4: >or=164 mg/dl) and nondiabetics (Q1: <14 mg/dl; Q2: 14-30 mg/dl; Q3: 30-60 mg/dl; Q4: >or=60 mg/dl). Patients were followed up for an average of 18 months after the occurrence of the acute coronary syndrome. RESULTS In diabetic patients, there was no relationship between the magnitude of the glycemia variation and in-hospital or postdischarge endpoints. In nondiabetics, no significant difference was observed in in-hospital mortality or morbidity, but statistically significant clinical differences were found during follow-up. Multivariate regression analysis showed that Q4 versus Q1, age >or=70 years, and previous antiplatelet or angiotensin-converting enzyme inhibitor therapy were independent predictors of postdischarge endpoints in the nondiabetic group. CONCLUSIONS In nondiabetic acute coronary syndrome patients, the magnitude of the variation in glycemia observed during hospitalization was a strong independent predictor of postdischarge clinical endpoints.