Effect of family history of type 2 diabetes on the intima-media thickness of the common carotid artery in normal-weight, overweight, and obese glucose-tolerant young adults.

OBJECTIVE To evaluate the effect of a first-degree family history of type 2 diabetes on the intima-media thickness of the common carotid artery (IMT-CCA), a surrogate marker of coronary atherosclerosis, in glucose-tolerant young adults. RESEARCH DESIGN AND METHODS IMT-CCA was measured by high-resolution B-mode ultrasound imaging in 401 individuals aged 18-45 years with normal glucose tolerance (NGT). A total of 213 subjects had no family history of type 2 diabetes until the third generation (FH(-)), and 188 subjects had a family history of type 2 diabetes (FH(+)), defined as having one or both parents with type 2 diabetes. Other measurements included: central fat accumulation, evaluated by waist circumference; insulin resistance, estimated by homeostasis model assessment for insulin resistance (HOMA(IR)); systolic and diastolic blood pressure; fasting and postload concentrations of glucose; fasting insulin levels; and lipid profile. RESULTS IMT-CCA and both 1- and 2-h postchallenge glucose concentrations were significantly higher in FH(+) than in FH(-) subjects. IMT-CCA was positively correlated with age, BMI, waist circumference, triglycerides, systolic and diastolic blood pressure levels, basal glucose concentrations, 1- and 2-h postchallenge glucose concentrations, and HOMA(IR). IMT-CCA was inversely associated with HDL cholesterol. After multivariate analysis, IMT-CCA maintained a significant association with family history of type 2 diabetes, BMI, waist circumference, HDL cholesterol, diastolic blood pressure, and fasting glucose. CONCLUSIONS This study indicates that a genetic predisposition to type 2 diabetes, probably in association with slightly elevated glucose levels, may accelerate the development of atherosclerosis and increase the risk for coronary heart disease in glucose-tolerant individuals.