Insulin-Induced Hypoglycemia and Mortality After Acute MI

Controversy surrounds the use of insulin for glucose control in patients with hyperglycemia after acute MI, because some data have suggested that hypoglycemia in these patients is associated with increased mortality. In this retrospective analysis of 7820 patients hospitalized for acute MI between January 1, 2000, and December 31, 2005, investigators assessed whether hypoglycemia, occurring either spontaneously or after insulin administration, is associated with increased in-hospital mortality. All subjects had glucose levels 140 mg/dL on admission.


Overall in-hospital mortality was significantly higher in patients who developed hypoglycemia than in those who did not. However, mortality in insulin-treated patients who developed hypoglycemia was not significantly higher than in insulin-treated patients who did not develop hypoglycemia. In multivariate analyses, hypoglycemia was an independent predictor of mortality in patients who did not receive insulin, but not in those who did.

Comment: The results of this large retrospective study suggest that hypoglycemia occurring during a hospital stay for MI is a marker for, but not a cause of, poor outcome. In view of recent findings suggesting that intensive glucose lowering does not confer cardiovascular benefit, these results are reassuring for clinicians facing the decision of whether to treat hyperglycemia after acute MI. The best target glucose level for such treatment, however, remains in dispute and must be determined by carefully designed clinical trials.
— JoAnne M. Foody, MD
Published in Journal Watch Cardiology April 29, 2009