Early carotid atherosclerosis in overweight non-diabetic individuals is associated with subclinical chronic inflammation independent of underlying insulin resistance.
Overweight in children and young adults is an increasing problem in Western industrialized countries with potential impact on cardiovascular morbidity. Whether early arterial wall thickening in these subjects mainly results from the often associated insulin resistance syndrome or from increased subclinical chronic inflammation probably triggered by adipose tissue is still under discussion. We therefore determined insulin sensitivity index (ISI) by performing an euglycaemic hyperinsulinaemic glucose clamp (insulin infusion rate 1 mU/kg/min) and high-sensitivity C-reactive protein (hsCRP) levels in relation to the intima-media thickness (IMT) at the common carotid artery (high resolution ultrasound; 13 MHz) in 81 young (age 33 +/- 1 years), moderately overweight subjects. To reduce the number of confounding variables, subjects with disturbances in glucose metabolism (75 g oral glucose tolerance test) and hypertension were excluded. As expected, higher BMI was positively correlated with increased IMT (r = 0.358; p = 0.001). After multiple regression analysis, hsCRP levels independently correlated to IMT (r = 0.251; p = 0.03), even after adjusting for age, sex, BMI, ISI, LDL cholesterol and smoking as cofactors. However, taking all above listed factors into account, glucose-clamp assessed insulin sensitivity was not correlated with IMT. Thus, overweight might trigger inflammatory mechanisms leading to vascular wall hypertrophy independent of the insulin resistance syndrome already early in life.
Balletshofer
B M
BM
Department of Endocrinology, Metabolism and Vascular Medicine, Eberhard-Karls-University Tübingen, Germany. bernd.balletshofer@med.uni-tuebingen.de
Haap
M
M
Rittig
K
K
Stock
J
J
Lehn-Stefan
A
A
Häring
H-U
HU
D000328:Adult; D002340:Carotid Artery Diseases / Q000209:etiology; D005260:Female; D006801:Humans; D007249:Inflammation / Q000150:complications / Q000209:etiology; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000150:complications