Stiffness Indexes β of the Common Carotid and Femoral Arteries Are Associated With Insulin Resistance in NIDDM

Abstract

OBJECTIVE To investigate the association between arterial wall stiffness indexes β of the common carotid artery (CCA) and the femoral artery (FA) and insulin resistance in NIDDM subjects in a cross-sectional study. RESEARCH DESIGN AND METHODS We evaluated the arterial stiffness indexes β of CCA and FA using an ultrasonic phase-locked echo-tracking system in 60 NIDDM subjects attending the diabetes center in Osaka City University Hospital, compared with 120 ageand sex-matched control subjects. Insulin sensitivity indexes were evaluated using a euglycemic-hyperinsulinemic clamp. RESULTS Stiffness indexes β of both CCA and FA were significantly higher in NIDDM subjects than in control subjects (CCA 18.1 ± 0.9 vs. 11.7 ± 0.3, respectively, P < 0.001; FA 35.7 ± 2.3 vs. 23.7 ± 0.8, respectively, P < 0.001). The mean insulin sensitivity index in NIDDM subjects was 4.69 ± 0.29 mg · kg⁻¹ · min⁻¹ · mU⁻¹ · 1. The stiffness indexes β of both CCA and FA were inversely correlated with insulin sensitivity indexes (CCA r = −0.393, P = 0.002; FA r = −0.329, P = 0.010), as well as with age, duration of diabetes, and mean blood pressure. In stepwise multiple regression analyses, insulin sensitivity index and duration of diabetes were identified as significant independent variables for stiffness indexes 3 in both CCA and FA (CCA R² = 0.249, P = 0.0003; FA R² = 0.336, P < 0.0001). CONCLUSIONS Arterial stiffness indexes β of CCA and FA were associated with insulin resistance in NIDDM subjects.