Prognostic value of admission glucose and glycosylated haemoglobin levels in acute coronary syndromes.

BACKGROUND Admission hyperglycaemia is associated with poorer prognosis in patients with an acute coronary syndrome (ACS). Whether hyperglycaemia is more important than prior long-term glucose metabolism, is unknown. AIM To investigate the prognostic value of admission glucose and HbA(1c) levels in patients with ACS. METHODS We measured glucose and HbA(1c) at admission in 521 consecutive patients with suspected ACS. Glucose was categorized as <7.8 (n = 305), 7.8-11.0 (n = 138) or > or =11.1 mmol/l (n = 78); HbA(1c) as <6.2% (n = 420) or > or =6.2% (n = 101). Mean follow-up was 1.6 +/- 0.5 years. RESULTS The diagnosis of ACS was confirmed in 332 patients (64%), leaving 189 (36%) with atypical chest pain. In ACS patients, mortality by glucose category (<7.8, 7.8-11.0 or > or =11.1 mmol) was 9%, 8% and 25%, respectively (p = 0.001); mortality by HbA(1c) category (<6.2% vs. > or =6.2%) was 10% vs. 17%, respectively (p = 0.14). On multivariate analysis, glucose category was significantly associated with mortality (HR 3.0, 95% CI 1.1-8.3), but HbA(1c) category was not (HR 1.5, 95%CI 0.6-4.2). DISCUSSION Elevated admission glucose appears more important than prior long-term abnormal glucose metabolism in predicting mortality in patients with suspected ACS.