Insulin resistance and intima-media thickness in the carotid and femoral arteries of clinically healthy 58-year-old men. The Atherosclerosis and Insulin Resistance Study (AZR)

Objective. To examine whether insulin resistance was associated with ultras ound-assessed measures of atherosclerosis in men with varying degrees of ob esity. Design. A random selection of subjects from the general population were div ided into quintiles of a body mass index/blood glucose score that was shown to be a valid and reproducible index of the degree of insulin sensitivity as assessed by the clamp technique. Every fourth man in quintiles 1 and 5 a nd every 20th man in quintiles 2-4 (in total, 104 men) were selected for an ultrasound examination of the carotid and femoral arteries and a euglycaem ic hyperinsulinaemic clamp examination, adjusted for fat-free mass. Setting. A university hospital. Subjects. A total of 104 clinically healthy 58-year-old men of Swedish ance stry. Results. The mean common carotid artery intima-media thickness (IMT), but n ot the common femoral IMT, correlated significantly with glucose infusion r ate (GIR) (r = -0.20, P < 0.05), systolic blood pressure (r = 0.20, P < 0.0 5), pulse pressure (r = 0.23 P < 0.01), heart rate (r = 0.20, P < 0.05), HD L cholesterol (r = -0.18, P < 0.05), log triglycerides (r = 0.28, P < 0.01) , apoA(1) (r = -0.20, P < 0.05), apoB (r = -0.22, P < 0.05) and plasma insu lin (r = 0.20, P < 0.05). In a multiple regression, common carotid IMT was independently associated with log triglycerides (<beta> = 0.21, P = 0.031) (R-2 = 8.7%, P = 0.005) Conclusions. Insulin sensitivity, measured with the gold standard euglycaem ic hyperinsulinaemic clamp method, showed similar associations with ultraso und-assessed measures of atherosclerosis in the carotid arteries as establi shed cardiovascular risk factors, but only triglycerides and pulse pressure contributed independently to the variability in the common carotid intima- media thickness.