Glycaemic responses to glucose and rice in people of Chinese and European ethnicity

Impact of diet on the efficacy of insulin lispro mix 25 and insulin lispro mix 50 as starter insulin in East Asian patients with type 2 diabetes: Subgroup analysis of the Comparison Between Low Mixed Insulin and Mid Mixed Insulin as Starter Insulin For Patients with Type 2 Diabetes Mellitus (CLASSIFY Study) randomized trial

Aims/Introduction

The pathophysiology of diabetes differs between Asian and Western patients in many ways, and diet is a primary contributor. The present study examined the effect of diet on the efficacy of 25% insulin lispro/75% insulin lispro protamine suspension (LM25) and 50% insulin lispro/50% insulin lispro protamine suspension (LM50) as starter insulin in Chinese and Japanese patients with type 2 diabetes and inadequate glycemic control with oral antidiabetic medication.

Materials and Methods

This was a predefined subgroup analysis of a phase 4, open‐label, 26‐week, parallel‐arm, randomized (computer‐generated random sequence) trial (21 January 2013 to 22 August 2014). Nutritional intake was assessed from food records kept by participants before study drug administration. Outcomes assessed were changes from baseline in self‐monitored blood glucose, 1,5‐anhydroglucitol and glycated hemoglobin.

Results

In total, 328 participants were randomized to receive twice‐daily LM25 (n = 168) or LM50 (n = 160). Median daily nutritional intake (by weight and percentage of total energy) was 230.8 g of carbohydrate (54%), 56.5 g of fat (31%) and 66 g of protein (15%). Improvements in self‐monitored blood glucose were significantly greater (P ≤ 0.028) in the LM50 group than in the LM25 group, regardless of nutritional intake. When carbohydrate (by weight or percentage energy) or fat (by weight) intake exceeded median levels, LM50 was significantly more efficacious than LM25 (P ≤ 0.026) in improving 1,5‐anhydroglucitol and glycated hemoglobin.

Conclusions

Glycemic control improved in both LM25 and LM50 groups, but LM50 was significantly more efficacious under certain dietary conditions, particularly with increased carbohydrate intake.

One-hour plasma glucose as a predictor of the development of Type 2 diabetes in Japanese adults

AIMS

To test the hypothesis that 1-h plasma glucose in an oral glucose tolerance test is a better predictor of the development of diabetes than 2-h plasma glucose, independently of indices of insulin secretion or action in Japanese adults.

METHODS

A historical cohort study was conducted in 1445 Japanese workers who did not have diabetes. The association between 1-h plasma glucose and the development of Type 2 diabetes was analysed.

RESULTS

Overall, 95 of the study participants developed Type 2 diabetes during a mean follow-up of 4.5 years. The area under the receiver-operating characteristic curve for 1-h plasma glucose for future diabetes [0.88 (95% CI 0.84-0.91)] was greater than that for 2-h plasma glucose [0.79 (95% CI 0.74-0.84)], and for insulinogenic [0.73 (95% CI 0.68-0.78)] and disposition indices [0.79 (95% CI 0.74-0.84); P < 0.05]. Compared with the first quartile, the hazard ratio for future diabetes in the fourth quartile of 1-h plasma glucose was 42.5 [95% CI 5.7-315.2 (P < 0.05)] and the hazard ratio in the fourth quartile of 2-h plasma glucose was 4.4 [95% CI 1.8-10.8 (P < 0.05)], after adjustments for covariates including fasting plasma glucose. The significance of the elevated hazard ratio in the fourth quartile of 1-h plasma glucose was maintained after adjustments for 2-h plasma glucose, insulinogenic index or disposition index, whereas the elevation of the hazard ratio in the fourth quartile of 2-h plasma glucose was diminished and was no longer significant after adjustments for 1-h plasma glucose.

CONCLUSIONS

One-hour plasma glucose had a greater association with the future development of Type 2 diabetes than did 2-h plasma glucose, independently of oral glucose tolerance test-derived indices of insulin action in a Japanese population.

THE DIABETES EPIDEMIC IN CHINA: AN INTEGRATED REVIEW OF NATIONAL SURVEYS

OBJECTIVE

To review trends in the prevalence and incidence of diabetes mellitus (DM) and related risk factors in China.

METHODS

We searched the literature using PubMed, China Knowledge Resource Integrated Database, and China Wanfang Digital Database for large epidemiologic studies and national surveys.

RESULTS

During the past 30 years (1980-2010), 7 national diabetes mellitus surveys were conducted in China mainland, indicating that the prevalence of DM has increased 17-fold, from 0.67 to 11.6% of the population. The prevalence of impaired glucose regulation (IGR, including impaired fasting glucose and impaired glucose tolerance) also increased, from 2.09 in 1994 to 27.2% in 2010. There was no national representative study of the incidence of diabetes to date; the reported incidence of type 2 diabetes during past 25 years in several cohort studies varied (2.7 to 15.8 per 1,000 person-years). Potential risk factors which could have contributed to the increasing prevalence and incidence of DM and IGR in the Chinese population include social and economic development, urbanization, dietary pattern, and Westernized lifestyle. Further, genetic studies have suggested that unique inheritable risk factors in the Chinese population may increase the risk for DM when compared to Caucasians.

CONCLUSION

DM and IGR have become epidemic in China. Public health strategies should focus on modifying lifestyle and dietary factors, particularly among those with a susceptible genetic background.

ABBREVIATIONS

BMI = body mass index DM = diabetes mellitus FBG = fasting blood glucose GWAS = genome-wide association study IGR = impaired glucose regulation IGT = impaired glucose tolerance OGTT = oral glucose tolerance test T2D = type 2 diabetes WC = waist circumference WHR = waist-hip ratio.

A systematic review of the influence of rice characteristics and processing methods on postprandial glycaemic and insulinaemic responses

Rice is an important staple food for more than half of the world's population. Especially in Asian countries, rice is a major contributor to dietary glycaemic load (GL). Sustained consumption of higher-GL diets has been implicated in the development of chronic diseases such as type 2 diabetes mellitus. Given that a reduction in postprandial glycaemic and insulinaemic responses is generally seen as a beneficial dietary change, it is useful to determine the variation in the range of postprandial glucose (PPG) and insulin (PPI) responses to rice and the primary intrinsic and processing factors known to affect such responses. Therefore, we identified relevant original research articles on glycaemic response to rice through a systematic search of the literature in Scopus, Medline and SciFinder databases up to July 2014. Based on a glucose reference value of 100, the observed glycaemic index values for rice varieties ranged from 48 to 93, while the insulinaemic index ranged from 39 to 95. There are three main factors that appear to explain most of the variation in glycaemic and insulinaemic responses to rice: (1) inherent starch characteristics (amylose:amylopectin ratio and rice cultivar); (2) post-harvest processing (particularly parboiling); (3) consumer processing (cooking, storage and reheating). The milling process shows a clear effect when compared at identical cooking times, with brown rice always producing a lower PPG and PPI response than white rice. However, at longer cooking times normally used for the preparation of brown rice, smaller and inconsistent differences are observed between brown and white rice.

Leisure-time, occupational, and commuting physical activity and risk of type 2 diabetes in Japanese workers: a cohort study

Background

Physical activity has been suggested to reduce the risk of type 2 diabetes. However, evidence is limited regarding whether vigorous-intensity activity yields the same benefits in preventing type 2 diabetes compared with an equivalent dose of moderate-intensity activity as well as other type of physical activity. We examined the risk of type 2 diabetes associated with exercise intensity during leisure and occupational and commuting physical activity among Japanese individuals.

Methods

Participants included 26,628 workers (23,207 men and 3,421 women) aged 30 to 64 years without diabetes at baseline. There was 6 years of follow-up maximum. Leisure-time exercise, occupational physical activity, and duration of walking to and from work were self-reported. Diabetes was diagnosed by using HbA_1c, fasting or random blood glucose, and self-report. We used Cox regression analysis to estimate the hazard ratio (HR) and the 95 % confidence interval (CI) of incident diabetes.

Results

During a mean follow-up of 5.2 years, 1,770 participants developed type 2 diabetes. Compared with individuals who engaged in no exercise, the HRs (95 % CIs) for <7.5, 7.5 to <15.0, and ≥15.0 MET-hours per week of exercise were 0.94 (0.81, 1.08), 1.07 (0.88, 1.30), and 0.90 (0.67, 1.21), respectively, among individuals who engaged in moderate-intensity exercise alone; 0.68 (0.44, 1.06), 0.86 (0.54, 1.34), and 0.89 (0.56, 1.41), respectively, among individuals who engaged in vigorous-intensity exercise alone; and 0.70 (0.44, 1.11), 0.57 (0.37, 0.90), and 0.76 (0.52, 1.11), respectively, among individuals who engaged in the two intensities, with adjustments for potential confounders and the total volume of exercise. Occupational physical activity and walking to and from work were not associated with diabetes.

Conclusions

The results suggest that vigorous-intensity exercise can reduce the risk of type 2 diabetes among Japanese workers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2362-5) contains supplementary material, which is available to authorized users.

Effect of ethnicity on glycaemic index: a systematic review and meta-analysis

Objectives:

Low glycaemic index (GI) foods are recommended to improve glycaemic control in diabetes; however, Health Canada considers that GI food labeling would be misleading and unhelpful, in part, because selected studies suggest that GI values are inaccurate due to an effect of ethnicity. Therefore, we conducted a systematic review and meta-analysis to compare the GI of foods when measured in Caucasians versus non-Caucasians.

Methods:

We searched MEDLINE, EMBASE and Cochrane databases for relevant articles. GI differences were aggregated using the generic inverse variance method (random effects model) and expressed as mean difference (MD) with 95% confidence intervals (95% CI). Study quality was assessed based on how well studies complied with official international GI methodology.

Results:

Review of 1288 trials revealed eight eligible studies, including 28 comparisons of GI among 585 non-Caucasians and 971 Caucasians. Overall, there was borderline significant evidence of higher GI in non-Caucasians than Caucasians (MD, 3.3 (95% CI, −0.1, 6.8); P=0.06) with significant heterogeneity (I², 46% P=0.005). The GI of eight types of rice was higher in non-Caucasians than Caucasians (MD, 9.5 (95% CI, 3.7, 23.1); P=0.001), but there was no significant difference for the other 20 foods (MD, 1.0 (95% CI, −2.5, 4.6); P=0.57). MD was significantly greater in the four low-quality studies (nine comparisons) than the four high-quality studies (19 comparisons; 7.8 vs 0.7, P=0.047).

Conclusions:

With the possible exception of rice, existing evidence suggests that GI values do not differ when measured in Caucasians versus non-Caucasians. To confirm these findings high-quality studies using a wide range of foods are required.

The role of digestive factors in determining glycemic response in a multiethnic Asian population

PURPOSE

There are wide inter-individual differences in glycemic response (GR). We aimed to examine key digestive parameters that influence inter-individual and ethnic differences in GR in healthy Asian individuals.

METHODS

Seventy-five healthy male subjects (25 Chinese, 25 Malays, and 25 Asian-Indians) were served equivalent available carbohydrate amounts (50 g) of jasmine rice (JR) and basmati rice (BR) on separate occasions. Postprandial blood glucose concentrations were measured at fasting (-5 and 0 min) and at 15- to 30-min interval over 180 min. Mastication parameters (number of chews per mouth and chewing time per mouthful), saliva α-amylase activity, AMY1 gene copy numbers and gastric emptying rate were measured to investigate their relationships with GR.

RESULTS

The GR for jasmine rice was significantly higher than for basmati rice (P < 0.001). The median number of AMY1 gene copies was 6, with a range of 2-15. There was a significant positive relationship between AMY1 copy number and α-amylase activity (P = 0.002). There were no significant ethnic differences in GR. For both rice varieties, the number of chews per mouthful was positively associated with the GR (JR, P = 0.011; BR, P = 0.005), while chewing time per mouthful showed a negative association (JR, P = 0.039; BR, P = 0.016). Ethnicity, salivary α-amylase activity, particle size distribution, gastric emptying rate and AMY1 gene copy numbers were not significant contributors to GR (P > 0.05).

CONCLUSION

Mastication parameters contribute significantly to GR. Eating slowly and having larger food boluses before swallowing (less chewing), both potentially modifiable, may be beneficial in glycemic control.

Glycaemic and insulin responses, glycaemic index and insulinaemic index values of rice between three Asian ethnic groups

Asians exhibit larger glycaemic response (GR) and insulin response (IR) than Caucasians, predisposing to an increased risk of type 2 diabetes mellitus (T2DM). We aimed to determine the GR and IR as well as the glycaemic index (GI) and insulinaemic index (II) of two rice varieties among three ethnic groups in Singapore. A total of seventy-five healthy males (twenty-five Chinese, twenty-five Malay and twenty-five Asian-Indians) were served the available equivalent carbohydrate amounts (50 g) of test foods (Jasmine rice and Basmati rice) and a reference food (glucose) on separate occasions. Postprandial blood glucose and plasma insulin concentrations were measured at fasting ( -5 and 0 min) and at 15, 30, 45, 60, 90 and 120 min after food consumption. Using the trapezoidal rule, GR, IR, GI and II values were determined. The GR did not differ between ethnic groups for Jasmine rice and Basmati rice. The IR was consistently higher for Jasmine rice (P=0·002) and Basmati rice (P=0·002) among Asian-Indians, probably due to compensatory hyperinsulinaemia to maintain normoglycaemia. The GI and II of both rice varieties did not differ significantly between ethnicities. The overall mean GI for Jasmine rice and Basmati rice were 91 (sd 21) and 59 (sd 15), respectively. The overall mean II for Jasmine rice was 76 (sd 26) and for Basmati rice was 57 (sd 24). We conclude that the GI values presented for Jasmine rice and Basmati rice were applicable to all three ethnic groups in Singapore. Future studies should include deriving the II for greater clinical utility in the prevention and management of T2DM.

Estimated effects of white rice consumption and rice variety selection on incidence of type 2 diabetes in Cambodia

Objective

Rice consumption patterns are considered an important risk factor for diabetes in many countries. The present study aimed to model the impact of a shift in consumption of white rice from current to appropriately reduced levels and a shift in rice variety from one with a high glycaemic index to one with a low glycaemic index, on the burden of type 2 diabetes in Cambodia.

Design

Prevent Plus software was used to model the impact of selected changes to white rice consumption on the burden of type 2 diabetes. Data used for modelling included: demographic projections, relative risk estimates for white rice consumption and diabetes, diabetes incidence, rice type and quantities consumed. The 10-year projections were based on different scenarios of changes in risk factors.

Results

With no intervention, 10-year projections showed that total new diabetes cases will increase from 11 315 (9·1 per 10 000 person-years) for the year 2011 to 14 852 new cases (12·4 per 10 000 person-years) in 2020. However, this increase will be reduced by 27 % (average across 10 years) with a change in rice variety from Phka Rumdual to IR66 and by 26 % (average across 10 years) with a 25 % reduction in quantity from current consumption levels.

Conclusions

Changing rice consumption patterns has potential for an important impact on diabetes risk, with a change of rice variety having a similar impact on the burden of diabetes in communities consuming rice with a high glycaemic index as a 25 % reduction in the quantity of rice consumed. Similar effects are likely for other countries with rice as a staple food, diversity in rice varieties and high incidence of diabetes.

The impact of eating methods on eating rate and glycemic response in healthy adults

Singapore is an island state that is composed of three major ethnic groups, namely Chinese, Malay and Indian. Its inhabitants consume food either using chopsticks (Chinese), fingers (Malay and Indian) or spoon (Chinese, Malay and Indian). Previous work by our group showed that the degree of mastication significantly influenced the glycemic response. The degree of mastication in turn may depend on the eating method as the amount of food taken per mouthful and chewing time differs between eating methods. Eleven healthy volunteers came in on six non-consecutive days to the laboratory and evaluated three methods of eating white rice (spoon, chopsticks and fingers) once and the reference food (glucose solution) three times in a random order. Their glycemic response (GR) was measured for the subsequent 120 min. Mastication parameters were determined using surface electrode electromyography. The GR to white rice eating with chopsticks was significantly lower than spoon. The GI of eating rice with chopsticks was 68 which is significantly lower than eating with spoon (GI=81). However there were no differences between fingers and spoon, and between fingers and chopsticks either in GR 120 min or GI. The inter-individual number of mouthful, number of chews per mouthful, chewing time per mouthful and the total time taken to consume the whole portion of rice were significantly different between spoon and chopsticks groups. Significant correlations between the number of mouthful to take the entire portion of rice and amount of rice per mouthful during mastication and the GR were observed for eating rice with spoon and chopsticks, but not for fingers. The results suggest that individual differences in number of mouthful and amount of rice per mouthful may be two of the causes for inter-individual differences in the GR between spoon and chopsticks. The present study suggests that eating rice with different feeding tools has different chewing times and amount of food taken per mouthful and then alters the GI of the rice.

Causes of type 2 diabetes in China

The prevalence of diabetes in China has increased substantially over recent decades, with more than 100 million people estimated to be affected by the disease presently. During this period there has been an increase in the rates of obesity and a reduction in physical activity. Many of the changes in lifestyle and diet are a result of increased economic development and urbanisation. In addition to an increasingly westernised diet, the traditional Chinese diet also plays a part, with the quantity and quality of rice intake linked to the risk of type 2 diabetes. Familial factors including inherited genetic variants are important, although differences in the genetic architecture suggest a different combination of genetic variants could be most relevant in Chinese when compared with Europeans. Recent advances have also emphasised the role of early life factors in the epidemic of diabetes and non-communicable diseases: maternal undernutrition, maternal obesity, and gestational diabetes are all linked to increased risk of diabetes in offspring. A mismatch between developmentally programmed biology and the modern environment is relevant for countries like China where there has been rapid economic transformation. Multisectoral efforts to address the risks will be needed at different stages throughout the lifecourse to reduce the burden of diabetes.

Acarbose monotherapy and weight loss in Eastern and Western populations with hyperglycaemia: an ethnicity-specific meta-analysis

OBJECTIVE

To demonstrate if weight loss achieved with acarbose in individuals with hyperglycaemia differs between Eastern and Western populations.

METHODS

Databases and reference lists of clinical trials on acarbose were searched. Eligible studies were randomised controlled trials of acarbose monotherapy in populations with hyperglycaemia of more than 12-week duration that provided data on body weight (BW) or body mass index (BMI).

RESULTS

A total of 34 trials (6082 participants) were included. The effect of acarbose on BW was superior to that of placebo [weighted mean difference (WMD) = -0.52, 95% confidence interval (CI) -0.78 to -0.25], nateglinide (WMD = -1.33, 95% CI -1.51 to -0.75) and metformin (WMD = -0.67, 95% CI -1.14 to -0.20). Compared with placebo, there was a significantly greater weight loss of 0.92 kg (p < 0.05, I(2)  = 88.8%) with acarbose in Eastern populations (WMD = -1.20, 95% CI -1.51 to -0.75) than that in Western populations (WMD = -0.28, 95% CI -0.59 to 0.03). Across all studies, the acarbose group achieved a significantly larger absolute weight loss of (change from baseline) 1.35 kg (p < 0.05, I(2)  = 94.3%) in Eastern populations (WMD = -2.26, 95% CI -2.70 to -1.81) than in Western populations (WMD = -0.91, 95% CI -1.36 to -0.47). Nevertheless, the possible risk of bias in Eastern studies may influence the results.

CONCLUSION

The effect of acarbose on weight loss seems to be more pronounced in Eastern than in Western populations with hyperglycaemia, and is superior to that of placebo, nateglinide and metformin across both ethnicities.

Amount, type, and sources of carbohydrates in relation to ischemic heart disease mortality in a Chinese population: a prospective cohort study

BACKGROUND

The relation between carbohydrate intake and risk of ischemic heart disease (IHD) has not been fully explored in Asian populations known to have high-carbohydrate diets.

OBJECTIVE

We assessed whether intakes of total carbohydrates, different types of carbohydrates, and their food sources were associated with IHD mortality in a Chinese population.

DESIGN

We prospectively examined the association of carbohydrate intake and IHD mortality in 53,469 participants in the Singapore Chinese Health Study with an average follow-up of 15 y. Diet was assessed by using a semiquantitative food-frequency questionnaire. HRs and 95% CIs were calculated by using a Cox proportional hazards analysis.

RESULTS

We documented 1660 IHD deaths during 804,433 person-years of follow-up. Total carbohydrate intake was not associated with IHD mortality risk [men: HR per 5% of energy, 0.97 (95% CI: 0.92, 1.03); women: 1.06 (95% CI: 0.99, 1.14)]. When types of carbohydrates were analyzed individually, starch intake was associated with higher risk [men: 1.03 (95% CI: 0.99, 1.08); women: 1.08, (95% CI: 1.02, 1.14)] and fiber intake with lower risk of IHD mortality [men: 0.94 (95% CI: 0.82, 1.08); women: 0.71 (95% CI: 0.60, 0.84)], with stronger associations in women than men (both P-interaction < 0.01). In substitution analyses, the replacement of one daily serving of rice with one daily serving of noodles was associated with higher risk (difference in HR: 26.11%; 95% CI: 10.98%, 43.30%). In contrast, replacing one daily serving of rice with one of vegetables (-23.81%; 95% CI: -33.12%, -13.20%), fruit (-11.94%; 95% CI: -17.49%, -6.00%), or whole-wheat bread (-19.46%; 95% CI: -34.28%, -1.29%) was associated with lower risk of IHD death.

CONCLUSIONS

In this Asian population with high carbohydrate intake, the total amount of carbohydrates consumed was not substantially associated with IHD mortality. In contrast, the shifting of food sources of carbohydrates toward a higher consumption of fruit, vegetables, and whole grains was associated with lower risk of IHD death.

The use of different reference foods in determining the glycemic index of starchy and non-starchy test foods

Background

Glycemic index (GI) is intended to be a property of food but some reports are suggestive that GI is influenced by participant characteristics when glucose is used as a reference.

Objective

To examine the influence of different reference foods on observed GI.

Design

The GIs of five varieties of rice and a sugary beverage (LoGiCane™) were tested in 31 European and 32 Chinese participants using glucose or jasmine rice as reference foods. The GIs of two ready-to-eat breakfast cereals (Kellogg’s cornflakes and Sustain) were tested in 20 younger and 60 older people using glucose or Sustain as reference foods.

Results

The GIs of rice tended to be higher in the Chinese compared with the Europeans when glucose was used as a reference (jasmine 80 vs 68, P = 0.033; basmati 67 vs 57, P = 0.170; brown 78 vs 65, P = 0.054; Doongara 67 vs 55, P = 0.045; parboiled 72 vs 57, P = 0.011). There were no between-group differences in GI when jasmine rice was the reference. The GIs of breakfast cereals tended to be lower in younger compared with older groups (cornflakes 64 vs 81, P = 0.008; Sustain 56 vs 66, P = 0.054). There was no between-group difference in the GI of cornflakes when Sustain was the reference (cornflakes 115 vs 120, P = 0.64). There was no ethnic difference in GI when glucose was the reference for another sugary food (LoGiCane™ 60 vs 62; P = 0.69).

Conclusions

A starchy reference may be more appropriate than a glucose beverage when attempting to derive universally applicable GI values of starchy foods.

Trial registration

The Chinese/European trial is registered with the Australian New Zealand Clinical Trials Registry as ACTRN12612000519853.

A Chinese risk score model for identifying postprandial hyperglycemia without oral glucose tolerance test

BACKGROUND

The aim of the study is to develop a risk score model for identifying postprandial hyperglycemia without oral glucose tolerance tests (OGTT) in Chinese population, and minimize the number of subjects needing further OGTT.

METHODS

Multivariable stepwise logistic regression was used to develop risk score models in a derivation cohort (7953 participants without known diabetes). The developed models were verified in a validation cohort (another 1455 subjects without known diabetes). All subjects had completed questionnaires, physical examination and OGTT. Performances of the risk score models were estimated using receiver operating characteristic curves.

RESULTS

Two risk score models for screening postprandial hyperglycemia were developed. The simple model used non-invasive risk factors (age, height, weight, waist, systolic blood pressure, pulse, hypertension, dyslipidemia and family history of diabetes mellitus), and the full model contained additional variables [fasting blood glucose (FBG), triglyceride/high density lipoprotein cholesterol] obtainable by invasive laboratory tests. The area under receiver operating characteristic curve (AUC) of simple model was similar to FBG and glycated haemoglobin. The full model has the largest AUC [0.799 (0.789-0.809) and 0.730 (0.702-0.758)] in both derivation and validation cohorts (p < 0.001 compared with simple model, FBG, and glycated haemoglobin). At a cutoff point of 80, the sensitivity, specificity and percentage that needed subsequent OGTT were 75.97, 67.56 and 48.38%, respectively.

CONCLUSIONS

We developed a risk score model for screening postprandial hyperglycemia based on routine clinical information. It could effectively identify patients at high-risk for postprandial hyperglycemia and remarkably reduce the number of subjects requiring OGTT.