Abstract 3560: Obstructive Sleep Apnea Exacerbates Endothelial Dysfunction In Patients With Metabolic Syndrome
Background: Both obstructive sleep apnea (OSA) and metabolic syndrome (MS) are well known as the risk factor of cardiovascular diseases, and are prevalent among obese patients. However, whether OSA deteriorates endothelial dysfunction in MS patients has not been determined. We therefore examined flow-mediated vasodilation (FMD) in MS patients with or without OSA.
Methods: We enrolled 49 overweight patients (body mass index ≥25, aged 35–69 years) and categorized into the 3 groups; patients with MS but not OSA (MS group, n=21), Group 2: patients with both MS and OSA (MS+OSA group, n=14), Group 3: patients with no risk factors but overweight (control group, n=14). MS was defined using the IDF criteria and OSA using polysomnography. FMD was measured using ultrasound as the percent change of the brachial artery diameter.
Results: Compared with the control group, MS group showed significantly lower %FMD (6.8±2.4 [mean±SD] vs 5.0±2.7, p<0.001) and HDL cholesterol, and higher triglycerides and hemoglobin A1c. Although there were no significant differences in classical risk factors between MS group and MS+OSA group, %FMD was significantly lower in MS+OSA group than in MS group (3.0±1.3 vs 5.0±2.7, p<0.001). On multiple regression analysis, OSA was significantly related to %FMD, independent of age, body mass index, blood pressure, LDL cholesterol, HDL cholesterol, triglycerides, fasting plasma glucose, and smoking (β=−0.328, p=0.02).
Conclusion: OSA exacerbates endothelial dysfunction in patients with MS, possibly leading to the increased risk of cardiovascular disease.