Predictive value of admission hyperglycaemia on mortality in patients with acute myocardial infarction

Abstract

Rationale and aim In patients with an acute myocardial infarction, admission hyperglycaemia (AH) is a major risk factor for mortality. However, the predictive value of AH, when the risk score and use of guidelines‐recommended treatments are considered, is poorly documented. Methods The first fasting plasma glucose levels after admission, risk level, guidelines‐recommended treatment use and 1‐year mortality were recorded. Patients with first fasting glucose level after admission > 7.7 mmo/l were considered to have AH. Results Three hundred and twenty patients with ST segment elevation myocardial infarction (STEMI) and 404 with non‐ST segment elevation myocardial infarction (NSTEMI) were included. One hundred and seventy‐five (24%) patients had pre‐existing diabetes (diabetes group), 154 (21%) had AH (AH+ group) and the remainding 395 (55%) had neither diabetes nor AH (AH– group). The Global Registry of Acute Coronary Events (GRACE) risk score was lower in the AH– group, but the use of guidelines‐recommended treatment was comparable in all groups. At 1 year, the mortality rate was higher in the AH+ group compared with the AH– group (18.8 vs. 6.1%, P < 0.01) and similar to that in the diabetes group (18.8 vs. 16.6%, P = NS). The relation between glycaemic status and mortality remained strong [AH+ vs. AH–, OR = 3.0 (1.5, 6.0) and diabetes vs. AH–, OR = 3.6 (1.7, 6.6)] after adjustment for the GRACE risk score [OR = 2.4 (1.8, 3.1) per 10% increase] and for treatment score [OR = 0.7 (0.6, 0.8) per 10% increase]. Conclusions In patients without a history of diabetes, the presence of AH indicates an increased risk of 1‐year mortality, similar to that of patients with diabetes, even when the risk score and use of guidelines‐recommended treatment are controlled for.