Impact of high-density lipoprotein cholesterol level in patients with variant angina pectoris

BackgroundIt is generally considered that patients with variant angina pectoris (VAP) have a potential disturbance in the coronary endothelium. High-density lipoprotein (HDL) has been shown to mediate vasodilation as a result of its endothelium-enhancing property; however, the significance of low HDL in patients with VAP has not been clarified. We sought to determine the association between a low level of high-density lipoprotein cholesterol (HDL-C) and VAP.MethodsWe examined a total of 174 consecutive patients who were suspected of having VAP and underwent spasm provocation test by direct injection of acetylcholine into the coronary arteries. One hundred and three patients (59%) were consequently diagnosed as having VAP. Serum HDL-C, fasting plasma glucose (FPG), and glycohemoglobin levels were measured in all patients.ResultsHDL-C in quartiles showed a significant negative correlation with the presence of VAP. Multivariate analysis revealed that the lowest HDL-C quartile (< 43 mg/dl), as well as cigarette smoking and impaired fasting glucose/diabetes mellitus, was an independent determinant of VAP (odds ratio = 3.39, P = 0.010). Patients in the highest FPG quartile (≥ 106 mg/dl) or with cigarette smoking habit in combination with the lowest HDL-C quartile showed an increased risk for VAP (relative risk = 2.01 and 1.88, respectively).ConclusionsA low level of HDL-C is an independent determinant for VAP. Endothelial dysfunction caused by a low HDL state may play a role in the development of VAP.