The Relationship of Insulin Resistance to High-Sensitivity C-Reactive Protein / 대한임상병리학회지

BACKGROUND: Insulin resistance is known as the common denominator of risk factors of atheros-clerosis as well as the major pathogenic process of type 2 diabetes mellitus (DM). Recently some investigators indicated the relationship of chronic inflammatory reaction to atherosclerosis and insulin resistance. We examined the relationship between insulin resistance and high sensitivity CRP (hs-CRP) in Koreans. METHODS: Twenty-five patients with type 2 DM and eleven healthy men were examined. Glucose disposal rate (GDR, mg/kg/min) was determined as the index of insulin resistance by the euglycemic insulin clamp test with De Fronzo method. The serum hs-CRP level was determined by Behring nephelometric assay, fibrinogen by functional assay, and plasminogen activator inhibitor-1 (PAI-1) by ELISA. We also included 81 healthy subjects to determine the reference range of hs-CRP. RESULTS: The reference range (median) of hs-CRP was 0-5.20 (0.56) mg/L. The hs-CRP concentration was not significantly different between control and DM groups. The GDR of DM (3.8+/-1.7) showed significantly decreased value compared with normal (8.4+/-1.5) group (P<0.001). In all subjects, there was no significant correlation of GDR and hs-CRP. CONCLUSTIONS: There was no significant correlation of GDR and hs-CRP. We think the interventional prospective study with anti-inflammatory drug is warranted to elucidate the independent relationship between insulin resistance and hs-CRP.

Mutations in Thyroid Hormone Receptor-beta Associated with Patients with Generalized Resistance and Pituitary Resistance to Thyroid Hormone / 대한내분비학회지

We report a point mutation in the TRbeta gene in korean patients with generalized resistance and pituitary resistance to thyroid hormone. One mutation at TRbeta (P453S) were detected in patient with pituitary resistance to thyroid, which showed different phenotype, generalized resistance to thyroid hormone, in her mothers. But, the other (C31Y), did not show clear relations with the disease. Therefore, further study of molecular and cellular basis will be warranted to explain the clear mechanism of the resistance to thyroid hormone.

Coronary Artery Calcification Quantified by Electron Beam Tomography as a Screening for Coronary Artery Disease in Asymptomatic Non-Insulin-Dependent-Diabetes Mellitus / 대한내과학회지

Patients with NIDDM are at increased risk for the development of coronary atherosclerosis and experience more silent myocardial infarction than non-diabetic subjects. The screening tools for early detection of coronary artery disease without significant narrowing has been requested in diabetic patients. Coronary artery calcification (CAC) score, quantified by electron beam computed tomography (EBT), have been reported to correlate with the amount of atherosclerotic plaque and vascular luminal narrowing. We investigated the distribution of CAC score and associated risk factors in asymptomatic NIDDM patients and patients with ischemic heart disease to estimate the usefulness of CAC as a screenig tool for ischemic heart disease in asymptomatic diabetes. METHOD: 136 NIDDM patients without any symptom of coronary artery disease and 37 patients with significant coronary artery stenosis were included. CAC were measured by electron bean tomography (ultrafast CT). Forty contiguous 3-mm thickness transverse two-dimensional sections were obtained through root of aorta and heart. Coronary calcification were defined as the presense of at least two adjacent pixel within the border of visualized coronary artery with CT number of at least 130 HU. Body mass index, waist-hip ratio were measured and body fat components were counted by impedence method. Visceral fat versus subcutaneous fat ratio were calculated by abdominal computed tomography. Plasma lipid profile, fasting insulin, C-peptide level, HbA1c concentration were measured. Correlations between natural log of CAC score and clinical parameters were evaluated and multiple regression analysis with natural log of CAC score as a independent variable was performed. Coronary angiography were performed in 17 asymptomatic NIDDM patients.. RESULT: CAC score was significantly higher in male than female subjects and increased significantly with aging (p<0.01). In patients with hypertension, previous history of cerebrovascular or peripheral vascular disease (p<0.05), CAC score was significantly increased. The CAC score showed significant positive correlations with smoking amount, duration of diabetes and a negative correlation with HDL-cholesterol (p<0.05). There were no association between CAC score and total cholesterol, LDL-cholesterol, waist to hip circumference ratio, or fasting insulin levels. After adjustment of compounding variables (age, sex), duration of diabetes, amount of smoking and previous history of atherosclerotic vascular disease were shown to be associated with CAC score. In multiple logistic regression analysis with natural log of CAC score as dependent variable, age, HDL-cholesterol, duration of diabetes, male gender were found to be significant independent variables. Seventeen diabetic patients with high CAC score, were taken coronary angiography and significant luminal narrowings (more than 50%) of coronary artery were documented in 16 patients. But, In 7 out of 17 patients with coronary one-vessel disease, coronary calcification were not detected by EBT. CONCLUSION: coronary artery calcium score quantified by electron beam computed tomography may be useful for screening of preclinical or asymptomatic coronary artery disease in asymptomatic NIDDM patients.