[Intensive insulin therapy in non-diabetic patients with myocardial infarction and hyperglycemia. INSUCOR study]

Hyperglycemia at admission has been associated with bad prognosis in patients with myocardial infarction (MI). The clinical benefit of intensive insulin treatment has been evaluated in diabetic patients admitted to intensive care units. The aim of our study was to assess the short-term effects and the safety of strict glycemic control in subjects with MI and hyperglycemia without a previous history of diabetes.

Twenty-eight non-previously diabetic patients admitted with MI and hyperglycemia were randomized to 2 treatment arms during the first 48 h: a) the intensive group (n = 13) received intravenous insulin with target glycemia levels of 80-110 mg/dl, and b) the conventional group (n = 15) received subcutaneous insulin only when glycemia was 160 mg/dl. High-sensitivity C-reactive protein was determined at 48 h and before discharge. An oral glucose tolerance test was performed after one month.

During the first 48 h, glycemia was significantly lower in the intensive than in the conventional group -mean (standard deviation): 104 (8) and 153 (54) mg/dl, respectively (p = 0.002)-, without any clinically significant hypoglycemic episodes. At 48 h, high-sensitivity C-reactive protein was significantly lower in the intensive group -44.3 (35.7) and 20.3 (20.3) mg/ml, respectively (p = 0.04)-. After 4 weeks, only 28.6% of patients showed normal response in the oral glucose tolerance test.

Intensive treatment with insulin to maintain near normoglycemia in non-diabetic patients with MI and hyperglycemia is feasible, safe and more effective than conventional treatment. In addition, it produces attenuation of inflammatory response. Our study also confirms the high prevalence of unknown abnormalities in glucose tolerance in subjects with MI.