Background: Admission hyperglycaemia is associated with an increased risk of mortality after myocardial infarction. Whether long-term glucose dysregulation (assessed by HbA1c) is more important than acute hyperglycaemia is unknown. We evaluated the prognostic value of admission glucose and HbA1c levels in nondiabetic patients with ST-segment elevation acute myocardial infarction (STEMI).
Methods: In 504 unselected, consecutive patients with STEMI, glucose and HbA1c levels were measured on admission. Glucose was categorised as <11.1 mmol/l (n=422) and >or= 11.1 mmol/l (n=82). HbA1c levels were categorised as <6.0% (n=416) and >or=6.0% (n=88). Mean follow-up was 1.6+/-0.6 years.
Results: Patients with hyperglycaemia on admission were comparable with those with normoglycaemia. However,patients with HbA1c >or=6.0%, as compared with those with HbA1c <6%, were older, were more often on beta-blockers and more frequently had multivessel disease. Thirty-day mortality in the subsequent glucose categories (<11.1 mmol/l and >or=11.1 mmol/l) was 4% and 19% (p<0.001) and in the subsequent HbA1c categories (<6% and >or=6%) was 5% and 12% (p=0.03). After multivariable analyses, admission glucose (OR 4.91,95% CI 2.03 to 11.9, p< 0.001) but not HbA1c (OR 1.33, 95%CI 0.48 to 3.71, p=0.58) was significantly associated with 30-day mortality. Among 30-day survivors, neither admission glucose nor HbA1c were predictors of long-term mortality.
Conclusion: Elevated admission glucose is an important predictor of 30-day outcome after STEMI, while prior long-term glucose dysregulation is a covariate of other high-risk clinical characteristics. Among 30-day survivors, neither admission blood glucose nor HbA1c were predictors of long-term outcome.