Relationship between high-density lipoprotein cholesterol levels and endothelial function in women: a cross-sectional study.

OBJECTIVES The purpose of this study was to evaluate the relationship between high-density lipoprotein cholesterol (HDL-C) levels and endothelial function in women. DESIGN Cross-sectional study. SETTING 22 university hospitals and affiliated clinics in Japan. PARTICIPANTS 1719 Japanese women aged 17-90 years who were not receiving lipid-lowering therapy. MEASURES We evaluated flow-mediated vasodilation (FMD) and serum levels of HDL-C. All participants were divided into four groups by HDL-C level: low HDL-C (<40 mg/dL), moderate HDL-C (40-59 mg/dL), high HDL-C (60-79 md/dL) and extremely high HDL-C (≥80 mg/dL). RESULTS Univariate regression analysis revealed a significant relationship between FMD and HDL-C (r=0.12, p<0.001). FMD values were significantly smaller in the low HDL-C group (5.2%±3.8%) and moderate HDL-C group (5.2%±3.8%) than in the extremely high HDL-C group (6.7%±3.4%) (p=0.024 and p=0.003, respectively), while there was no significant difference in FMD between the high HDL-C group and the extremely high HDL-C group. Multiple logistic regression analysis did not show a significant association between HDL-C levels and FMD. CONCLUSIONS Endothelial function increased in relation to HDL-C levels. However, there was no association of HDL-C levels with endothelial function after adjustment of traditional cardiovascular risk factors in women. TRIAL REGISTRATION NUMBER UMIN000012950; Results.