Myocardial infarction and carbohydrate metabolism relating to diabetes mellitus.

Fifteen non-obese males with acute myocardial infarction and no diabetic history were evaluated for diabetes. During infarction, results of oral glucose tolerance tests were "diabetic" or "probably diabetic" in 10 of the 15 patients (67 percent). The plasma immuno-reactive insulin response in 12 patients (80 percent) was of a pattern observed in patients with maturity-onset diabetes. Six months after infarction, follow-up glucose tolerance tests in 12 surviving patients were diabetic or probably diabetic in three cases (25 percent). In seven of twelve patients (58 percent) had delay in the peaking of the plasma insulin response to an oral glucose tolerance test, a phenomenon that is observed in patients with maturity-onset diabetes. Glucose tolerance tests were abnormal in one of fourteen control subjects (7 percent). There was a delayed plasma insulin response to an oral glucose test in two of fourteen controls (14 percent). Patients with myocardial infarction have an increased incidence of diabetes mellitus.