Background: The relationship between plasma glucagon-like peptide-1 (GLP-1) and coronary plaque characteristics in humans remains unclear.
Methods and Results: A total of 85 culprit coronary vessels excluding the 10-mm culprit segments in non-diabetic patients with acute coronary syndrome (ACS) were examined using integrated backscatter intravascular ultrasound, performed using a 40-MHz intravascular catheter before PCI. All patients underwent 75-g oral glucose tolerance test (OGTT), and the plasma GLP-1 response was evaluated on the basis of the area under the GLP-1 concentration-time curve (GLP-1 AUC) from 0 to 120 min. Patients in the low GLP-1 AUC tertile had a significantly greater percentage lipid area than did patients in the intermediate and high tertiles (low tertile vs. intermediate tertile vs. high tertile: 57.3+/-12.1% vs. 47.2+/-15.4% vs. 46.3+/-12.7%, P<0.01, ANOVA) and a smaller percentage fibrosis area (38.1+/-9.4% vs. 44.6+/-11.5% vs. 45.7+/-9.0%; P=0.01, ANOVA). On multiple regression analysis, low GLP-1 AUC tertile was independently associated with percentage lipid area.
Conclusions: Low plasma GLP-1 during 75-g OGTT is associated with increased lipid content in non-diabetic patients with ACS, suggesting that plaque vulnerability is increased in this subgroup of patients.