Impaired Glucose Tolerance and the Likelihood of Nonfatal Stroke and Myocardial Infarction

Abstract

Background and Purpose —Although diabetes mellitus (DM) is known to increase the risk of cardiovascular disease (CVD), the effect of impaired glucose tolerance (IGT) on the risk remains unclear. We determined whether IGT was associated with an increased likelihood for stroke and myocardial infarction in a nationally representative sample of US adults. Methods —We evaluated the association between IGT (defined as a fasting glucose level of <140 mg/dL and a plasma glucose level of between 140 and 200 mg/dL 2 hours after administration of 75 grams of an oral glucose load) and DM (defined as the current use of insulin or an oral hypoglycemic medication, a fasting plasma glucose level of >140 mg/dL, or a plasma glucose level of >200 mg/dL 2 hours after administration of an oral glucose load) with a self-reported physician diagnosis of stroke and myocardial infarction in 6547 adults aged 40 to 74 years participating in the Third National Health and Nutrition Examination Survey. Multivariate logistic regression analyses were used to investigate these relationships. Results —IGT and DM were observed in 1494 and 1532 adults, respectively. After adjustment for differences in age, gender, race/ethnicity, education, hypertension, cholesterol, body mass index, and cigarette smoking, IGT was not associated with stroke (odds ratio [OR], 0.9; 95% confidence interval [CI], 0.5 to 1.6) or myocardial infarction (OR, 1.1; 95% CI, 0.7 to 1.6). DM was associated with both stroke (OR, 1.6; 95% CI, 1.0 to 2.6) and myocardial infarction (OR, 1.9; 95% CI, 1.3 to 2.8). Conclusions —In contrast to DM, IGT was not associated with an increased likelihood of prevalent nonfatal stroke or myocardial infarction.