Stress hyperglycaemia and increased risk of death after myocardial infarction in patients with and without diabetes: a systematic overview

Background High blood glucose concentration may increase risk of death and poor outcome after acute myocardial infarction. We did a systematic review and metaanalysis to assess the risk of in-hospital mortality or congestive heart failure after myocardial infarction in patients with and without diab etes who had stress hyperglycaemia on admission. Methods We did two searches of MEDLINE for English-language articles publis hed from 1966 to October, 1998, a computerised search of Science Citation I ndex from 1980 to September, 1998, and manual searches of bibliographies. T wo searchers identified all cohort studies or clinical trials reporting in- hospital mortality or rates of congestive heart failure after myocardial in farction in relation to glucose concentration on admission. We compared the relative risks of in-hospital mortality and congestive heart failure in hy perglycaemic and normoglycaemic patients with and without diabetes. Findings 14 articles describing 15 studies were identified. Patients withou t diabetes who had glucose concentrations more than or equal to range 6.1-8 .0 mmol/L had a 3.9-fold (95% CI 2.9-5.4) higher risk of death than patient s without diabetes who had lower glucose concentrations. Glucose concentrat ions higher than values in the range of 8.0-10.0 mmol/L on admission were a ssociated with increased risk of congestive heart failure or cardiogenic sh ock in patients without diabetes. In patients with diabetes who had glucose concentrations more than or equal to range 10.0-11.0 mmol/L the risk of de ath was moderately increased (relative risk 1.7 [1.2-2.4]). Interpretation Stress hyperglycaemia with myocardial infarction is associat ed with an increased risk of in-hospital mortality in patients with and wit hout diabetes; the risk of congestive heart failure or cardiogenic shock is also increased in patients without diabetes.