Independent predictors of the severity of angiographic coronary atherosclerosis: the lack of association between impaired glucose tolerance and stenosis severity

Independent predictors of the severity of coronary atherosclerosis are ill defined. We sought to determine the predictors and examine the association of impaired glucose tolerance with stenosis severity. Four hundred thirty-seven patients were studied who underwent coronary angiography for suspected coronary artery disease. Serum concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDLc), lipoprotein(a) Lp(a)] and apolipoproteins (Apo A-I and Apo B) were measured and low-density lipoprotein cholesterol (LDLc) concentration was calculated. Except the patients treated for diabetes mellitus (DM), patients were classified into three groups such as normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and DM by glucose tolerance test. Coronary atherosclerosis index (CAI) representing the severity of coronary atherosclerosis was determined by summation of the stenosis score of all lesions on coronary angiograms. Results indicated that age, total amount of cigarettes smoked, Apo B/Apo A-I, and LDLc/HDLc correlated with CAI, whereas HDLc and Apo A-I concentrations inversely correlated with CAI. TC, TG, Lp(a), LDLc, Apo B concentrations and body mass index did not correlate with CAI. One- and two-hour plasma glucose concentrations and the area of plasma glucose concentration under the curve at the glucose tolerance test did not correlate with CAI, revealing that post-challenge glycemia is not associated with stenosis severity. CAI in IGT patients was significantly lower than that in DM patients but did not differ from that in NGT patients, indicating that IGT does not affect the stenosis severity. Multivariate analysis showed that age, male gender, Apo B/Apo A-I, DM, systemic hypertension, and total amount of cigarettes smoked were independent predictors of CAI.