Background This study aims to evaluate admission blood glucose level (BGL) in patients presenting to the emergency department (ED) as a risk factor for a major adverse cardiac event (MACE) on presentation and up to 30 days post discharge. Admission BGL is a prognostic indicator in patients with confirmed acute coronary syndrome (ACS). It is unclear if admission BGL improves the diagnosis and stratification of patients presenting to the ED with suspected ACS.

Methods This study is an analysis of data collected from a prospective observational study. The study population consisted of ED patients from Brisbane, Australia and Christchurch, New Zealand. Patients were enrolled between November 2007 and February 2011. Admission BGL was taken as part of routine admission blood with fasting status unknown. The primary end point for this study was a MACE at presentation and up to 30 days post discharge. Logistic regression analyses examined the relationship between admission hyperglycaemia and MACE. A hyperglycaemic threshold of 7 mmol/L was chosen based on WHO standards.

Results A total of 1708 patients were eligible. A MACE was identified in 336 patients (19.7%) within 30 days. Of these 98 had confirmed unstable angina and 232 had non-ST elevation myocardial infarction. Hyperglycaemia was identified in 476 (27.9%) patients with 147 (30.9%) having a MACE. Admission BGL >7 mmol/L was demonstrated as an independent predictor of a MACE (OR1.51 CI 1.06 to 2.14). Gender, age, hypertension, dyslipidaemia, family history, ischaemic ECG and positive troponin remained important factors.

Conclusions Admission BGL is an independent risk factor for a MACE in patients with suspected ACS. Hyperglycaemia should be considered a risk factor for MACEs and consideration be given to its inclusion in existing diagnostic tools.