Acceptability of HbA1c values as a diagnostic tool for diabetes mellitus in Korea / 대한내과학회지

BACKGROUND/AIMS: In 2010, the American Diabetes Association (ADA) adopted glycated hemoglobin (HbA1c) as a new diagnostic criterion for diabetes mellitus. However, HbA1c values may differ among races. We determined whether this criterion could be applied to Korean diabetics. METHODS: Between January 2000 and January 2010, 1,862 patients among Konyang University Hospital visitors in which the 75 g oral glucose tolerance test (OGTT) and HbA1c were checked at the same time were enrolled. We excluded patients with acute disease, an Hb or = 2 mg/dL, those prescribed oral hypoglycemic agents or insulin, and those who were pregnant. RESULTS: After applying the exclusion criteria, 1,474 Korean patients were enrolled. All had common features of Korean diabetics for body mass index and homeostatic model assessment of insulin resistance values. Using the 0 and 120 minute glucose levels of the OGTT from the receiver operating characteristic curve, the HbA1c cutoff value was 6.25%. The cutoff value to diagnose diabetes with the presence of diabetic retinopathy was 6.75%. CONCLUSIONS: Our study showed a difference between the HbA1c values for diagnosing diabetes and the new diagnostic criterion from the ADA. Considering that the HbA1c characteristics may be influenced by race or culture, larger studies on diabetes complications are needed to identify the appropriate HbA1c value for Korean diabetics.

Is Arterial Stiffness Useful in Differentiating Patients with Coronary Artery Disease from Risk Factor Only Patients?

BACKGROUND AND OBJECTIVE: The endothelial function, carotid intima-media thickness (CIMT) and arterial stiffness are known as surrogates of atherosclerosis, but it is not clear whether these surrogates can discriminate patients with coronary artery disease (CAD) from those with risk factor. The intention was to compare these 3 surrogates in patients with CAD and those with risk factor only. SUCJECTS AND METHODS: Forty-three patients with CAD (mean age:58, 32 men), 18 age and sex matched healthy people (mean age:52, 9 men) and 16 patients (mean age:53, 12 men) with atherosclerosis risk factor only were enrolled. The endothelial function (flow-mediated brachial artery dilation, FMD) and CIMT were measured by high-resolution ultrasound and the arterial stiffness by an oscillometric method. RESULTS: There was a significant difference between the CAD and risk factor groups (3.46+/-1.3% vs. 5.77+/-2.54%, p0.05) in the measured FMD. The CIMT showed a significant difference between the CAD and healthy groups (0.89+/-0.14 mm vs. 0.78+/-0.07 mm, p0.05). There were significant differences among all groups in relation to the arterial stiffness (CAD group:1524+/-289 cm/sec, risk group:1342+/-202 cm/sec, healthy group:1195+/-119 cm/sec, p<0.05). The arterial stiffness showed significant correlation with the FMD (r=-0.322, p=0.005) and CIMT (r=0.310, p=0.007). CONCLUSION: Of the 3 surrogates, the arterial stiffness measurement showed the best reliability in differentiating the CAD from the risk factor only groups as well as from healthy subjects. This study suggests the arterial stiffness can be used as a novel noninvasive test for early diagnosis of CAD in patients at high risk of atherosclerosis.