Possible risk factors of carotid artery atherosclerosis in the Japanese population: A primary prevention study in non-diabetic subjects

Objective Hyperinsulinemia has been associated with the risk of coronary he art disease, stroke, and renal disease in nondiabetic subjects. However, di rect evidence that hyperinsulinemia per se is directly associated with athe rosclerosis has been conflicting. The present study was designed to investi gate the cross-sectional association of carotid artery atherosclerosis with insulin, independent of well-known cardiovascular risk factors, in nondiab etic subjects. Methods and Subjects Between 1996 and 1997, 1,335 subjects (620 men and 715 women) were recruited from one Japanese community, interviewed, and examin ed. Clinical measurements in the study included intimal-medial thickness (I MT) of the carotid artery, fasting plasma insulin, serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low- density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), hemo globin type HbA(1c), systolic blood pressure (SBP), diastolic blood pressur e (DBP), and body mass index (BMI). We divided the subjects of both genders into three subgroups according to age (40-49 years of age; 50-59; and 60-6 9). Results Using simple regression analysis, we found that IMT was significant ly correlated with at least one of TC, LDL-C, HbA(1c), SBP, DBP, and BMI in each subgroup. The results of multivariate analysis showed that IMT was in dependently correlated with TC, HDL-C, LDL-C, SEP and BMI in males and with TC, TG, HDL-C, LDL-C, HbA(1c), SEP, DBP, and BMI in females. Insulin level s showed no correlation with IMT in either males or females. Conclusion Fasting hyperinsulinemia does not appear to be correlated with c arotid artery atherosclerosis based on the present cross-sectional results.