Serum glucose levels and hospital outcomes in patients with acute myocardial infarction without prior diabetes: a community-wide perspective

BACKGROUND AND OBJECTIVES: Elevated serum glucose levels are associated with an increased risk of adverse outcomes in patients with diabetes in the setting of acute myocardial infarction. It is, however, unclear whether a similar association exists in nondiabetic patients and whether this relationship is changing over time. The objectives of this population-based investigation were to examine the magnitude of elevated glucose levels in patients with acute myocardial infarction and the association between admission serum glucose levels and hospital outcomes in patients not known to have prior diabetes. METHODS: The sample consisted of 3601 patients without a history of prior diabetes who were hospitalized with acute myocardial infarction at all greater Worcester (Massachusetts) medical centers in five biennial periods between 1995 and 2003. RESULTS: The average age of our study population was 70 years, 59% were men, and the average glucose level at the time of hospital admission was 149 mg/dl. Approximately one-third of patients presented with glucose levels<120 mg/dl, whereas one-quarter had serum glucose levels>or=160 mg/dl. Patients in the uppermost quintiles of serum glucose were significantly more likely to develop heart failure and cardiogenic shock, and die during hospitalization than patients with lower serum glucose levels. Patients with the highest glucose levels were less aggressively treated with effective cardiac medications and coronary interventions. CONCLUSIONS: The results of this population-based investigation provide insights into the magnitude and impact of hyperglycemia in patients not known to have prior diabetes who are hospitalized with acute myocardial infarction. Increased surveillance and more aggressive treatment strategies are needed to improve the outlook of patients with elevated serum glucose levels.