Admission glycemia: a predictor of death after acute coronary syndrome in non-diabetic patients?

BACKGROUND: Previous studies have demonstrated that acute phase hyperglycemia is associated with increased in-hospital mortality in diabetic patients admitted with acute coronary syndrome (ACS), but this has not been clearly demonstrated in non-diabetic patients. The present study was designed to determine whether admission hyperglycemia (AG) is an independent predictor of in-hospital and six-month mortality after ACS in non-diabetic patients.

METHODS: This was a retrospective cohort study of 426 non-diabetic patients consecutively admitted with ACS. The patients were stratified into quartile groups according to AG, which was also analyzed as a continuous variable. Vital status was obtained at six-month follow-up in 96.8% of the patients surviving hospitalization. Logistic regression analysis was used to identify independent predictors of in-hospital and six-month death.

RESULTS: Of the 426 patients included in the study (age 62.6 years+/-13.1, 77% male), 22 (5.4%) patients died during hospitalization and 20 (5.2% of the patients surviving hospitalization) within six months of ACS. Mean AG was 134.89 mg/dl+/-51.95. The higher the AG, the more probable was presentation with ST-segment elevation ACS (STEMI), anterior STEMI, higher heart rate, Killip class higher than one (KK >1), higher serum creatinine and greater risk of in-hospital and six-month death. In multivariate analysis, only age (OR=1.10; 95% CI 1.04-1.17), STEMI (OR=3.02; 95% CI 1.07-8.50), AG (OR=1.073; 95% CI 1.004-1.146), serum creatinine (OR=1.10; 95% CI 1.009-1.204) and KK >1 on admission (OR=4.65; 95% CI 1.59-13.52) were independently associated with in-hospital death. Age (OR=1.07; 95% CI 1.03-1.12), serum creatinine (OR=1.09; 95% CI 1.01-1.18) and in-hospital development of heart failure (OR=2.34; 95% CI 1.07-5.10) were independently associated with higher risk of death within six months of ACS.

CONCLUSIONS: AG is an independent predictive factor of in-hospital death after ACS in non-diabetic patients. Although it did not show an independent association with higher risk of six-month death, AG appears to contribute to it, since the risk is greater the higher the AG. Its predictive value may have been blunted by the insufficient power of the sample and/or by the time interval between acquisition of AG and the evaluated endpoint.