High fasting glucose levels as a predictor of worse clinical outcome in patients with coronary artery disease: results from the Bezafibrate Infarction Prevention (BIP) study

Background A high fasting glucose level may be a marker not only for microvascular complications, but also for macrovascular complications. We evaluated the clinical significance of a high fasting glucose level (≥110 mg/dL), detected either at baseline or during follow-up, in the Bezafibrate Infarction Prevention (BIP) study. Methods The BIP study was a secondary prevention prospective double-blind study comparing bezafibrate to placebo. A total of 3122 patients with documented coronary artery heart disease who were aged 45 to 74 years and had a total cholesterol level between 180 and 250 mg/dL, low-density lipoprotein cholesterol level ≤180 mg/dL, a high-density lipoprotein cholesterol level ≤45 mg/dL, a triglyceride level ≤300 mg/dL, and a fasting glucose ≤160 mg/dL were randomized to receive 400 mg of bezafibrate daily or placebo. Results The primary end point of the BIP study was fatal myocardial infarction, non-fatal myocardial infarction, or sudden death. Secondary end points included hospitalization for unstable angina, percutaneous transluminal coronary angioplasty, and coronary artery bypass grafting. At baseline, 330 patients (11%) had diabetes mellitus, and 293 patients (9%) had an impaired fasting blood glucose level (IFG). During 6.2 years of follow-up, diabetes mellitus developed in 186 patients (6%), IFG developed in 366 patients (12%), and 62% of patients remained with normal fasting glucose levels (NFG). Patients with diabetes mellitus and IFG both at baseline or developing during follow-up had a significantly higher rate of secondary end points than paients with NFG (P <.0001). Bezafibrate treatment reduced secondary end points only in patients with NFG (P = .04). Conclusion Diabetes mellitus and IFG were common in the BIP study and were predictive of a worse clinical outcome that was not attenuated with bezafibrate treatment.