Apolipoprotein B and insulin resistance are good markers of carotid atherosclerosis in patients with type 2 diabetes mellitus

Background: it is widely known that low-density lipoprotein cholesterol (LDL-C) is an established risk factor for atherosclerosis. However, recent studies reported that serum levels of apolipoprotein B (Apo B) and Apo B to apolipoprotein A-1 (Apo A-1) ratio were better predictors of atherosclerotic vascular disease compared with LDL-C. In this study, we investigated that Apo B concentrations and insulin resistance (HOMA-R) can be good markers of carotid atherosclerosis in patients with type 2 diabetes. Methods: Sixty-six type 2 diabetic patients with carotid atherosclerosis and 66 age- and sex-matched patients without carotid atherosclerosis were compared. The usefulness in risk assessment of LDL-C, Apo B, and HOMA-R for carotid atherosclerosis were estimated by receiver-operating characteristics (ROC) curve analysis. The percentage of carotid atherosclerosis in combination with two of these markers was calculated. Results: Type 2 diabetic patients with carotid atherosclerosis had significantly higher body mass index, higher blood pressure, higher LDL-C, and Apo B, and higher HOMA-R. The ranking of the area under the ROC curve was Apo B, HOMA-R, and LDL-C (0.70,0.69, and 0.66, respectively). The percentage of patients with carotid atherosclerosis and high LDL-C was 60.7%, high LDL-C + high HOMA-R was 77.4%, and high Apo B + high HOMA-R was 90.9%, respectively. The usefulness of these combinations was significantly better than that of LDLC alone (p < 0.05 and p < 0.01, respectively). Conclusions: In conclusion, the combination of Apo B and HOMA-R is a superior marker of carotid atherosclerosis compared with LDL-C alone in patients with type 2 diabetes. (C) 2008 Elsevier Ireland Ltd. All rights reserved.