The 1h post glucose value best predicts future dysglycemia among normal glucose tolerance subjects.

AIM: To analyse the OGTT glycemic parameters - fasting, 1h and 2h plasma glucose values singly and in various combinations; with respect to their prediction of future dysglycemia in subjects with normal glucose tolerance (NGT). METHODS: Electronic medical records of individuals who underwent an OGTT between 1991 and 2016 at a tertiary diabetes centre were analysed. NGT subjects who had at least one more follow up OGTT (n=1356) were selected for the study. Regarding their prediction of future dysglycemia, the glycemic parameters-Fasting plasma glucose (FPG), 1h plasma glucose (1HrPG) and 2h plasma glucose (2HrPG) were analysed separately and also in different combinations. HbA1c and the combined use of HbA1c and FPG were also compared. Receiver operating characteristic (ROC) curve analysis was performed to assess the capability of various glycemic parameters to discriminate between NGT and dysglycemia. The WHO criteria were used to define dysglycemia as the presence of prediabetes (Impaired fasting glucose and/or Impaired glucose tolerance) or diabetes. RESULTS: 318(23.4%) developed prediabetes (median follow up 3.5years) and 134(10%) developed diabetes (median follow up 5.6years). The 1hrPG had a significantly higher AUC (0.684, 0.716) compared to FPG (0.560 and 0.593) and 2hrPG (0.644 and 0.618) for prediabetes and diabetes respectively. Adding the FPG or the 2hrPG to the 1HrPG did not significantly improve the AUC beyond 1HrPG alone. The 1HrPG also predicted diabetes better than HbA1c as well as the combined use of HbA1c and FPG. CONCLUSION: The 1HrPG value during OGTT is a good predictor of future dysglycemia among NGT subjects.

Metabolic profile of normal glucose-tolerant subjects with elevated 1-h plasma glucose values.

AIM: The aim of this study was to compare the metabolic profiles of subjects with normal glucose tolerance (NGT) with and without elevated 1-h postglucose (1HrPG) values during an oral glucose tolerance test (OGTT). METHODOLOGY: The study group comprised 996 subjects without known diabetes seen at tertiary diabetes center between 2010 and 2014. NGT was defined as fasting plasma glucose <100 mg/dl (5.5 mmol/L) and 2-h plasma glucose <140 mg/dl (7.8 mmol/L) after an 82.5 g oral glucose (equivalent to 75 g of anhydrous glucose) OGTT. Anthropometric measurements and biochemical investigations were done using standardized methods. The prevalence rate of generalized and central obesity, hypertension, dyslipidemia, and metabolic syndrome (MS) was determined among the NGT subjects stratified based on their 1HrPG values as <143 mg/dl, ≥143-<155 mg/dl, and ≥155 mg/dl, after adjusting for age, sex, body mass index (BMI), waist circumference, alcohol consumption, smoking, and family history of diabetes. RESULTS: The mean age of the 996 NGT subjects was 48 ± 12 years and 53.5% were male. The mean glycated hemoglobin for subjects with 1HrPG <143 mg/dl was 5.5%, for those with 1HrPG ≥143-<155 mg/dl, 5.6% and for those with 1HrPG ≥155 mg/dl, 5.7%. NGT subjects with 1HrPG ≥143-<155 mg/dl and ≥155 mg/dl had significantly higher BMI, waist circumference, systolic and diastolic blood pressure, triglyceride, total cholesterol/high-density lipoprotein (HDL) ratio, triglyceride/HDL ratio, leukocyte count, and gamma glutamyl aminotransferase (P < 0.05) compared to subjects with 1HrPG <143 mg/dl. The odds ratio for MS for subjects with 1HrPG ≥143 mg/dl was 1.84 times higher compared to subjects with 1HrPG <143 mg/dl taken as the reference. CONCLUSION: NGT subjects with elevated 1HrPG values have a worse metabolic profile than those with normal 1HrPG during an OGTT.

ß-Cell Function and Insulin Sensitivity in Normal Glucose-Tolerant Subjects Stratified by 1-Hour Plasma Glucose Values.

AIM: This study was designed to assess ß-cell function and insulin sensitivity indices among normal glucose tolerance (NGT) subjects stratified by 1-h plasma glucose (1hPG) values during an oral glucose tolerance test (OGTT). MATERIALS AND METHODS: One hundred sixty-six NGT subjects underwent a five-point OGTT, and glucose and insulin levels were estimated. We calculated the following indices: (a) ß-cell function (homeostasis assessment model-ß-cell function [HOMA-ß] and Insulinogenic Index [IGI]) and (b) insulin sensitivity (homeostasis assessment model-insulin resistance [HOMA-IR], Matsuda Index, and Insulin Sensitivity Index [ISI]). RESULTS: NGT subgroups with elevated 1hPG values (i.e., 1hPG ≥143 to <155 mg/dL and 1hPG ≥155 mg/dL) did not differ from those with 1hPG <143 mg/dL by HOMA-ß (P = 0.236) but had significantly lower IGIs (367 ± 239 vs. 257 ± 243 vs. 246 ± 239; P = 0.019). With respect to ISIs, HOMA-IR was not significantly different among the groups (P = 0.103). However, the Matsuda Index (11.2 ± 5.0 vs. 7.4 ± 4.8 vs. 5.5 ± 4.9; P < 0.001) and ISI (0.015 ± 0.010 vs. 0.012 ± 0.006 vs. 0.011 ± 0.011; P = 0.028) were significantly lower in subjects with elevated 1hPG values. CONCLUSIONS: NGT subjects with elevated 1hPG levels have alterations in ß-cell function and insulin sensitivity compared with those with normal 1hPG levels.

Use of capillary blood glucose for screening for gestational diabetes mellitus in resource-constrained settings.

AIMS: The aim of the study was to evaluate usefulness of capillary blood glucose (CBG) for diagnosis of gestational diabetes mellitus (GDM) in resource-constrained settings where venous plasma glucose (VPG) estimations may be impossible. METHODS: Consecutive pregnant women (n = 1031) attending antenatal clinics in southern India underwent 75-g oral glucose tolerance test (OGTT). Fasting, 1- and 2-h VPG (AU2700 Beckman, Fullerton, CA) and CBG (One Touch Ultra-II, LifeScan) were simultaneously measured. Sensitivity and specificity were estimated for different CBG cut points using the International Association of Diabetes in Pregnancy Study Groups (IADPSG) criteria for the diagnosis of GDM as gold standard. Bland-Altman plots were drawn to look at the agreement between CBG and VPG. Correlation and regression equation analysis were also derived for CBG values. RESULTS: Pearson's correlation between VPG and CBG for fasting was r = 0.433 [intraclass correlation coefficient (ICC) = 0.596, p < 0.001], for 1H, it was r = 0.653 (ICC = 0.776, p < 0.001), and for 2H, r = 0.784 (ICC = 0.834, p < 0.001). Comparing a single CBG 2-h cut point of 140 mg/dl (7.8 mmol/l) with the IADPSG criteria, the sensitivity and specificity were 62.3 and 80.7 %, respectively. If CBG cut points of 120 mg/dl (6.6 mmol/l) or 110 mg/dl (6.1 mmol/l) were used, the sensitivity improves to 78.3 and 92.5 %, respectively. CONCLUSIONS: In settings where VPG estimations are not possible, CBG can be used as an initial screening test for GDM, using lower 2H CBG cut points to maximize the sensitivity. Those who screen positive can be referred to higher centers for definitive testing, using VPG.

1-hour venous plasma glucose and incident prediabetes and diabetes in Asian indians.

BACKGROUND: This study evaluated 1-h plasma glucose (1HrPG) levels during an oral glucose tolerance test (OGTT) in predicting progression to diabetes and prediabetes among individuals with normal glucose tolerance (NGT). SUBJECTS AND METHODS: After analyzing the electronic records of 32,809 subjects who had undergone an OGTT, we identified 1,179 subjects who had NGT at baseline, defined as fasting plasma glucose (FPG) of < 100 mg/dL and 2-h plasma glucose (2HrPG) of < 140 mg/dL, who had at least one follow-up OGTT. Receiver operating characteristic curves were constructed to derive the optimal 1HrPG values, which were associated with the development of diabetes (FPG of ≥ 126 mg/dL or 2HrPG of ≥ 200 mg/dL) or prediabetes (FPG ≥ 100 to <1 26 mg/dL or 2HrPG of ≥ 140 to < 200 mg/dL) at follow-up in these NGT subjects. RESULTS: On follow-up, 148 (12.6%) subjects developed diabetes, and 392 (33.2%) developed prediabetes. In those with 1HrPG values ≥ 155 mg/dL, 19.5% converted to diabetes compared with 10% among those with 1HrPG of ≥143 to < 155 mg/dL and 6.6% in those with 1HrPG < 143 mg/dL. Comparative figures for conversion to prediabetes were 52.2% (1HrPG values ≥ 155 mg/dL), 39.3% (1HrPG ≥ 143 to <155 mg/dL), and 26.0% (1HrPG < 143 mg/dL). The time to development of diabetes (mean ± SE) was also significantly shorter among those with 1HrPG values of ≥ 155 mg/dL (9.0±0.3 years) compared with those with 1HrPG ≥ 143 to < 155 mg/dL (10.6 ± 0.5 years) and 1HrPG < 143 mg/dL (11.6 ± 0.2 years). CONCLUSIONS: Among NGT subjects with elevated 1HrPG values during an OGTT, progression to diabetes and prediabetes is greater, and the rate of progression is also faster.

Comparison of capillary whole blood versus venous plasma glucose estimations in screening for diabetes mellitus in epidemiological studies in developing countries.

BACKGROUND: This study compared capillary blood glucose (CBG) measurements with venous plasma glucose (VPG) measurements in screening for diabetes and prediabetes in epidemiological studies. METHODS: Four hundred seven subjects ≥ 20 years old (54.1% male) without previously known diabetes underwent oral glucose tolerance tests at a tertiary diabetes center in Chennai, India. Simultaneous measurements of CBG (OneTouch(®) Ultra(®) meter, LifeScan, a Johnson & Johnson Company, Milpitas, CA) and VPG (AU2700, Beckman, Fullerton, CA) were performed, both in the fasting state and 2 h after a 75-g glucose load (2-h post-glucose [PG]). Diabetes, impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) were defined using American Diabetes Association (ADA) and World Health Organization (WHO) criteria. RESULTS: The mean fasting CBG and VPG values were 122 ± 39 mg/dL and 115 ± 40 mg/dL, respectively, and the 2-h PG values were 203 ± 84 mg/dL and 176 ± 85 mg/dL, respectively. The Pearson's correlation coefficient for CBG with VPG was 0.681 (P < 0.001) in the fasting state and 0.897 (P < 0.001) for the 2-h PG load, indicating good correlation between the two methods. Based on the ADA fasting criteria, 31.9% versus 21.1% (capillary vs. venous) had diabetes, whereas based on the WHO criteria, 43.2% versus 38.6% (capillary vs. venous) had diabetes. The accuracy of identifying diabetes was 83.3% by the ADA and 90.9% by WHO criteria, for IGT it was 85.3%, and for IFG it was 66.3% by the ADA and 72.2% by the WHO criteria. CONCLUSION: CBG is a feasible alternative for screening of diabetes and IGT in epidemiological studies in developing countries where obtaining venous samples may be difficult.