The relationship between insulin resistance syndrome, body fat distribution, dietary intake variables and subclinical atherosclerosis in obese type 2 diabetes.

摘要

Introduction. Cardiovascular disease is the leading cause of mortality in type 2 diabetic subjects. However, it is not certain whether fat deposition or insulin resistance syndrome are independently related to the cardiovascular changes associated with type 2 diabetes mellitus. The current study was designed to evaluate the relationship between insulin resistance and its associated metabolic changes, body fat and diet and measures of subclinical atherosclerosis.; Materials & methods. Data for 52 recently diagnosed obese type 2 DM patients were used for the present analysis. Insulin resistance was measured using the hyperinsulinemic euglycemic clamp. Body fat composition was measured using DEXA and CT. Dietary assessment was conducted using a Block's FFQ and the average of two 24-hours dietary recalls. Measures of subclinical vascular disease (SVD) included: assessment of arterial stiffness by pulse wave velocity (PWV); ultrasound measurement of the carotid artery intimal-medial thickness (IMT) and plaque index (PI) and measurement of coronary calcification (CCS) and aortic calcification (ACS) by electron beam computed tomography (EBCT).; Results. PWV significantly and independently related to hepatic fat, BMI and diastolic blood pressure. IMT related significantly and independently to age and blood glucose. Glycosylated hemoglobin (HbAlc) was the only significant correlate of the plaque index. Only age and insulin sensitivity index were independently related to CCS. Age was the only significant independent correlate of ACS. A strong inter-relationship was found between CCS and ACS, IMT and PWV. MIT was also related positively to ACS. IMT and PWV were related to CCS independent of the cardiovascular risk factors. Dietary intake of cholesterol and saturated fat related positively to the degree of IMT. Dietary intake of arginine was significantly and negatively associated with the CCS and ACS.; Conclusions. Measures of subclinical atherosclerosis evaluate different aspects of vascular disease. While early functional changes (arterial stiffness) are strongly associated with obesity indices, measures of late structural changes (IMT and coronary calcifications) are highly correlated with insulin resistance and its associated dyslipidemia. In concordance, measures of structural changes are significantly and positively associated with each other.