Endothelial function in patients with and without diabetes mellitus with different degrees of coronary artery stenosis.

PURPOSE: To evaluate endothelial function using flow-mediated dilatation (FMD) of the brachial artery in patients with and without diabetes mellitus (DM) with different degrees of coronary artery stenosis. METHOD: We investigated 293 patients, 69 (23.6%) of whom had DM. FMD and coronary arteriography were performed. RESULTS: Patients with DM had a significantly lower FMD (mean +/- SD, 3.7 +/- 3.8%) compared with patients without DM (mean +/- SD, 5.2 +/- 5.3%) (p < 0.05). When the results were broken down by the severity of coronary artery disease (CAD) (no significant coronary artery stenosis, 1-vessel disease, 2-vessel disease, and 3-vessel disease) the only statistically significant difference between diabetics and nondiabetics was found in patients without significant coronary stenosis (mean FMD +/- SD: 5.2 +/- 4.4% in diabetics, 7.6 +/- 5.4% in nondiabetics [p < 0.05]). CONCLUSION: In CAD patients, the presence of DM was associated with endothelial dysfunction. The difference in the FMD was clearly expressed between patients with and without DM in the subgroup without significant coronary stenosis, and was no longer present with advanced coronary atherosclerosis.