Introduction:The association between coronary artery disease (CAD) and diabetes mellitus (DM) is strong but the physiologic mechanism remains unproven. Prior research shows that diabetics have upregulated levels of proteins and lipoproteins called advanced glycation end products (AGEs), which cause oxidative damage to the vascular endothelium. The accumulation of AGEs may act as a contributing factor to the development of disease states such as CAD. sRAGE, the soluble form of the AGE receptor can mediate these effects by binding circulating AGEs.Hypothesis:Our study investigated whether the levels of AGEs (Pentosidine and N(6)-carboxymethyllysine [CML]), and sRAGE are markers for the presence and extent of CAD in patients with or without DM.Methods:We recruited 364 patients with suspected CAD who presented for cardiac catheterization. Evaluated laboratory data included levels of HbA1C, creatinine and lipid profile. Serum pentosidine, CML and sRAGE levels were measured by ELISA protein quantification. SYNTAX scores were calculated after the angiography was performed. Regression analysis was used to examine the relationship between serum AGE and sRAGE concentrations, HbA1c and SYNTAX score.Results:52% of the subjects were male. 48% of the subjects were diabetic and 10% of these patients were on insulin injection. 72% of the participants were on a daily statins. 13% of the subjects were active smokers. 53% of the participants had obstructive CAD. The results suggested that higher pentosidine levels were found in subjects with high SYNTAX scores, but this correlation was not statistically significant. CML and sRAGE levels also did not significantly correlate with the SYNTAX score. However, there was a strong positive correlation between HbA1C levels and the SYNTAX score [Spearman correlation coefficient of 0.26, ? < 0.0001 for the entire group; ? = 0.01 for patients without diabetes and ?= 0.0001 for patients with diabetes].Conclusions:Our results demonstrate that in patients with suspected CAD undergoing cardiac catheterization, SYNTAX score correlates positively with HbA1C but not with AGE or sRAGE levels. More in-depth analysis is required to identify the particular AGEs that may play a role in the development and the advancement of CAD.