Association of remnant-like particle cholesterol with coronary artery disease in patients with normal total cholesterol levels

Background Limited information is available as to whether there is a differ ence in the association of lipid and fibrinolytic variables with coronary a rtery disease according to the presence or absence of elevated serum total cholesterol, We examined the levels of various lipid and fibrinolytic varia bles including remnant-like particle cholesterol (RLP-C). RLP-C is a recent ly established simple assay method for the estimation of triglyceride-rich lipoprotein remnants. Methods and Results Levels of total cholesterol, low-density lipoprotein ch olesterol, high-density lipoprotein cholesterol: (HDL-C), triglyceride, lip oprotein(a), RLP-C, uric acid, blood glucose, tissue plasminogen activator, tissue plasminogen activator inhibitor type 1, antithrombin III, and prote in C were measured in 208 patients who underwent diagnostic coronary angiog rams. Of these 208 patients, 57 were hypercholesterolemic (greater than or equal to 220 mg/dl) and 151 were normocholesterolemic. HDL-C showed signifi cant differences between patients with rid those without angiographically d etermined coronary artery stenosis in both hypercholesterolemic and normoch olesterolemic patients (P = .0025 and P = .0003, respectively). Both RLP-C and uric acid showed significant differences only in the normocholesterolem ic subgroup (P = .0006 and P = .0060, respectively). This difference in uri c acid was not significant by multivariable analysis. The ratio of RLP-C/HD L-C was demonstrated to be highly significantly (P < .0001) associated with coronary artery stenosis in patients with normal total cholesterol, wherea s there was no statistically significant association in the hypercholestero lemic patient subgroup. Conclusions Our current study disclosed that RLP-C levels are strongly asso ciated with coronary artery disease, especially:in-patients with normal tot al cholesterol levels. Moreover, RLP-C/HDL-C ratio may be even more signifi cantly associated:with the presence of coronary artery stenosis in normocho lesterolemic patients.