Atchara Thamprasit

Regional Abdominal Fat Distribution in Lean and Obese Thai Type 2 Diabetic Women: Relationships With Insulin Sensitivity and Cardiovascular Risk Factors

To determine the relationships of body fat distribution and insulin sensitivity and cardiovascular risk factors in lean and obese Thai type 2 diabetic women, 9 lean and 11 obese subjects, with respective mean age 41.7 +/- 6.3 (SD) and 48.0 +/- 8.5 years, and mean body mass index (BMI) 23.5 +/- 1.8 and 30.3 +/- 3.7 kg/m2, were studied. The amount of total body fat (TBF) and total abdominal fat (AF) were measured by dual-energy x-ray absorptiometer, whereas subcutaneous (SAF) and visceral abdominal fat areas (VAF) were measured by computerized tomography (CT) of the abdomen at the L4-L5 level. Insulin sensitivity was determined by euglycemic hyperinsulinemic clamp. Cardiovascular risk factors, which included fasting and post-glucose challenged plasma glucose and insulin, systolic (SBP) and diastolic blood pressure (DBP), lipid profile, fibrinogen, and uric acid, were also determined. VAF was inversely correlated with insulin sensitivity as determined by glucose infusion rate (GIR) during the clamp, in both lean (r=-0.8821; P=.009) and obese subjects (r=-0.582; P=.078) independent of percent TBF. SAF and TBF were not correlated with GIR. With regards to cardiovascular risk factors, VAF was correlated with SBP (r=0.5279; P=.024) and DBP (r=0.6492; P=.004), fasting insulin (r=0.7256; P=.001) and uric acid (r=0.4963; P=.036) after adjustment for percent TBF. In contrast, TBF was correlated with fasting insulin (r=0.517; P=.023), area under the curve (AUC) of insulin (r=0.625; P=.004), triglyceride (TG) (r=0.668; P=.002), and uric acid (r=0.49; P=.033). GIR was not correlated with any of cardiovascular risk factors independent of VAF. In conclusion, VAF was a strong determinant of insulin sensitivity and several cardiovascular risk factors in both lean and obese Thai type 2 diabetic women.

Insulin resistance in subjects with a history of thyrotoxic periodic paralysis (TPP)

Background  Hyperinsulinaemia has been suggested as an important factor for developing hypokalaemic paralysis in patients with thyrotoxic periodic paralysis (TPP). Since hyperinsulinaemia is a common feature of insulin resistance, there may be a causal relationship between insulin resistance and TPP.

Relationships of body fat distribution, insulin sensitivity and cardiovascular risk factors in lean, healthy non-diabetic Thai men and women

In order to study the relationships of body fat distribution, insulin sensitivity and cardiovascular risk factors in lean, healthy non-diabetic Thai men and women, 32 healthy, non-diabetic subjects, 16 men and 16 women, with respective mean age 28.4+/-6.6 (S.D.) and 32.8+/-8.9 years, mean BMI 21.0+/-2.8 and 21.2+/-3.7 kg/m(2), were measured for total body fat and abdominal fat by dual energy X-ray absorptiometry (DEXA), anthropometry and insulin sensitivity by euglycemic hyperinsulinemic clamp. Cardiovascular risk factors included fasting and post-glucose challenge plasma glucose and insulin, blood pressure, lipid profile, fibrinogen and uric acid. For similar age and BMI, men had a lower amount and percent of total body fat, but had a higher proportion of abdominal/total body fat than women. In men, insulin sensitivity, as determined by glucose infusion rate during euglycemic hyperinsulinemic clamp, was inversely correlated with total body fat, abdominal fat, BMI and waist circumference, whereas only total body fat, but not abdominal fat, BW and hip circumference were inversely correlated with insulin sensitivity in women. No cardiovascular risk factors, except area under the curve (AUC), of plasma insulin in women correlated with insulin sensitivity when adjusted for total body fat. After age adjustment, total body fat was better correlated with fasting and AUC of plasma glucose and insulin in men and with systolic blood pressure as well as triglyceride levels in women. Only HDL-C in men was better correlated with abdominal fat. In conclusion, there were sex-differences in body fat distribution and its relationship with insulin sensitivity and cardiovascular risk factors in lean, healthy non-diabetic Thai subjects. Total body fat was a major determinant of insulin sensitivity in both men and women, abdominal fat may play a role in men only. Body fat, not insulin sensitivity, was associated with cardiovascular risk factors in these lean subjects.

A comparison between a 75-g and 100-g oral glucose tolerance test in pregnant women.

Objectives: To test the validity of a 75‐g, 2‐h oral glucose tolerance test (OGTT) for diagnosing gestational diabetes mellitus (GDM) using the criteria and reference values suggested by the American Diabetes Association for the 100‐g, 3‐h OGTT. Methods: The results of a 75‐g, 2‐h OGTT were compared with those of a 100‐g, 3‐h OGTT in 42 pregnant women. The womens mean±S.D. age and gestational age were 33.6±5.4 years and 28.2±4.2 weeks, respectively. Each subject was randomly scheduled within 1 week for both the 75‐g and 100‐g OGTTs. Results: The mean plasma glucose concentrations at 1, 2, and 3 h during the 100‐g OGTT were significantly higher than those during the 75‐g OGTT. Using the Carpenter and Coustan criteria, the prevalence of GDM was 21.4% when using the 100‐g, 3‐h OGTT, whereas it was found to be at only 7.1% when using the 75‐g, 2‐h OGTT. Conclusions: Plasma glucose responses during the 75‐g OGTT were found to be lower than those during the 100‐g OGTT. When using the same diagnostic criteria, the prevalence of GDM was also found lower using the 75‐g glucose load. It would therefore not be appropriate to use the 75‐g OGTT for diagnosing GDM using the criteria and reference values of the 100‐g OGTT. To give a comparable prevalence of GDM, the threshold of abnormal plasma glucose levels of the 75‐g OGTT would need to be lower than that of the 100‐g OGTT.

Insulin resistance in women with a history of severe pre-eclampsia.

Aim:  This study investigated whether post‐partum insulin resistance existed in women with a history of severe pre‐eclampsia.

Comparison the Carpenter and Coustan thresholds with the new thresholds obtained from Thai pregnant women for the diagnosis of gestational diabetes

AIMS To determine the threshold of plasma glucose levels calculated from the mean+2SDs for diagnosing gestational diabetes mellitus (GDM) in Thai women. METHODS Thai pregnant women without pre-existing diabetes were invited into the study. A 100-g oral glucose tolerance test (OGTT) was performed in all participants during their second or third trimesters, regardless of the results of 50-g glucose challenge test. RESULTS Seven hundred and ninety seven women with singleton pregnancy participated in the study. The distribution of 1-, 2-, and 3-h plasma glucose levels of the 100-g OGTT was Gaussian. The rounded cut-off point values calculated from the mean+2SDs were 90, 195, 170, and 155 mg/dl, respectively for fasting, 1-, 2-, and 3-h plasma glucose. With the Carpenter and Coustan thresholds, 52 women (6.5%, 95%CI 4.9-8.5%) were diagnosed as GDM. Of these, when tested with the new thresholds, 30 had normal glucose tolerance and 22 were diagnosed as GDM. CONCLUSION By using mean+2SDs of plasma glucose levels of the 100-g OGTT as the threshold for diagnosing GDM, the thresholds at 1, 2, and 3h obtained from Thai women were 15 mg/dl higher than those of the Carpenter and Coustan thresholds.