Usefulness of revised fasting plasma glucose criterion and characteristics of the insulin response to an oral glucose load in newly diagnosed Japanese diabetic subjects

Curcuma longa extract reduces serum inflammatory markers and postprandial hyperglycemia in healthy but borderline participants with overweight and glycemia in the normal/prediabetes range: a randomized, double-blind, and placebo-controlled trial

The spice turmeric, which has the Latin name Curcuma longa (C. longa), has various physiological effects. This study evaluated the effects of a hot water mixture with supercritical carbon dioxide C. longa extracts, CLE, and the potential active components of C. longa, turmeronols A and B and bisacurone on inflammation and glucose metabolism. First, we investigated the effect of CLE and the potential active components of C. longa on lipopolysaccharide-induced inflammation in RAW264.7 macrophages. We found a significant decrease in the production of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and nitric oxide with CLE, turmeronol A, and bisacurone, Significant inhibition of each of these substances was also observed, except for TNF-α with turmeronol B. The second part of our work was a 12-week randomized, double-blind, placebo-controlled study in healthy but borderline adults aged 40 to 69 years with overweight and normal/prediabetes glycemia. We compared blood inflammatory and glycometabolic markers in the CLE (n = 55) and placebo groups (n = 55). We found significantly lower serum high-sensitivity C-reactive protein and hemoglobin A1c levels in the CLE group. This group also showed significant improvements in postprandial hyperglycemia and insulin sensitivity indices. Our findings indicate that CLE may reduce low-grade inflammation and thus improve insulin sensitivity and postprandial hyperglycemia. Clinical trial registration: https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000051492, UMIN-CTR, UMIN000045106.

Trends in the high blood glucose and non-alcoholic fatty liver disease among Korean adolescents

High blood glucose level and non-alcoholic fatty liver disease (NAFLD) in adolescents are long-term risk factors for cardiovascular diseases and poor prognosis. We investigated recent trends of high blood glucose levels and NAFLD among Korean adolescents aged 12-18 years. We conducted a cross-sectional analysis using data of 5,685 adolescents aged 12-18 years from the Korea National Health and Nutrition Examination Surveys (KNHANES), from 2007-2009 to 2016-2018. Linear trends in the prevalence of high blood glucose level, NAFLD, and associated factors were assessed using multivariable logistic regression analyses. During the study period, the odds ratios for high blood glucose level and NAFLD increased significantly in both sexes and in girls, respectively (p for trend <0.05). Over-consumption of total calories in boys and fat intake in boys and girls increased significantly (p for trend <0.05). In Korean adolescents, the prevalence of high blood glucose level and NAFLD has increased recently. Efforts to modify the associated factors and further research to determine the public health measures are warranted to prevent these metabolic abnormalities in adolescents.

Comparison of tofogliflozin 20 mg and ipragliflozin 50 mg used together with insulin glargine 300 U/mL using continuous glucose monitoring (CGM): A randomized crossover study

To investigate whether sodium glucose co-transporter 2 inhibitors (SGLT2i), tofogliflozin or ipragliflozin, achieve optimal glycemic variability, when used together with insulin glargine 300 U/mL (Glargine 300). Thirty patients with type 2 diabetes were randomly allocated to 2 groups. For the first group: After admission, tofogliflozin 20 mg was administered; Fasting plasma glucose (FPG) levels were titrated using an algorithm and stabilized at 80 mg/dL level with Glargine 300 for 5 days; Next, glucose levels were continuously monitored for 2 days using continuous glucose monitoring (CGM); Tofogliflozin was then washed out over 5 days; Subsequently, ipragliflozin 50 mg was administered; FPG levels were titrated using the same algorithm and stabilized at 80 mg/dL level with Glargine 300 for 5 days; Next, glucose levels were continuously monitored for 2 days using CGM. For the second group, ipragliflozin was administered prior to tofogliflozin, and the same regimen was maintained. Glargine 300 and SGLT2i were administered at 8:00 AM. Data collected on the second day of measurement (mean amplitude of glycemic excursion [MAGE], average daily risk range [ADRR]; on all days of measurement) were analyzed. Area over the glucose curve (<70 mg/dL; 0:00 to 6:00, 24-h), M value, standard deviation, MAGE, ADRR, and mean glucose levels (24-h, 8:00 to 24:00) were significantly lower in patients on tofogliflozin than in those on ipragliflozin. Tofogliflozin, which reduces glycemic variability by preventing nocturnal hypoglycemia and decreasing postprandial glucose levels, is an ideal SGLT2i when used together with Glargine 300 during basal insulin therapy.

Comparison Between Effectiveness of 100 mg/day Sitagliptin and a Switch to Mitiglinide Calcium Hydrate/Voglibose from 50 mg/day Sitagliptin in Patients with Type 2 Diabetes

We analyzed the effects of 100 mg/day sitagliptin and a switch to mitiglinide calcium hydrate/voglibose compound tablets (MIT/VOG) in patients with type 2 diabetes mellitus (T2DM) treated with 50 mg/day sitagliptin. Five patients with T2DM treated with 50 mg/day sitagliptin and hemoglobin A1c (HbA1c) of ≥6.5% were switched to MIT/VOG, or the dose of sitagliptin was increased to 100 mg/day. The effects of the changes in therapy were compared in a crossover fashion by continuous glucose monitoring. The primary endpoint was mean amplitude of glycemic excursions (MAGE), and the secondary end points were 24-hour mean blood glucose level and mean blood glucose level from 0:00 a.m. to 7:00 a.m. and from 7:00 a.m. to 0:00 a.m., percentage of time with blood glucose level of ≥200 mg/dl and <70 mg/dl, maximum and minimum blood glucose levels, and increases in postprandial blood glucose levels. MAGE was significantly lower with MIT/VOG (P = 0.016), whereas mean blood glucose levels were lower between 0:00 a.m. and 7:00 a.m. with 100 mg/day sitagliptin. The percentage of time with blood glucose level ≥200 mg/dl was significantly shorter with MIT/VOG (P = 0.041). The maximum blood glucose level was significantly lower with MIT/VOG (P = 0.043), and the minimum was significantly lower with 100 mg/day sitagliptin (P = 0.043). Blood glucose levels after dinner and mean increases in postprandial blood glucose levels were significantly lower with MIT/VOG (P = 0.090 and P = 0.045 respectively). In patients with T2DM, treatment with MIT/VOG improves MAGE and postprandial hyperglycemia and 100 mg/day sitagliptin lowers early morning glucose levels. This trial was registered with the University Hospital Medical Information Network (UMIN) (No. UMIN R000008274).

Comparison of morning basal + 1 bolus insulin therapy (insulin glulisine + insulin glargine 300 U/mL vs insulin lispro + insulin glargine biosimilar) using continuous glucose monitoring: A randomized crossover study

INTRODUCTION

We compared the effects of morning administration of insulin glulisine + insulin glargine 300 U/mL (G + G300) with that of insulin lispro + insulin glargine biosimilar (L + GB).

MATERIALS AND METHODS

A total of 30 patients with type 2 diabetes who wore a continuous glucose monitoring device on admission after glucose levels were stabilized by morning long-acting and ultra-rapid-acting insulins were randomly allocated to groups who received G + G300 on days 1 and 2, and the same dose L + GB on days 3 and 4, or vice versa. Data collected on days 2 and 4 (mean amplitude of glycemic excursion, mean of daily differences: all days) were analyzed. Insulin was injected at 08.00 h. A day was defined as the period from 08.00 h one day, to 08.00 h the next day. Test meals were given.

RESULTS

Increased post-breakfast glucose level, post-breakfast glucose gradient, mean glucose level, standard deviation and M-value (24 h, 00.00-06.00 h), mean amplitude of glycemic excursion, and mean of daily differences were significantly lower in patients taking G + G300 than those taking L + GB (P ≤ 0.0001-0.04). The area over the glucose curve (<70 mg/dL) was not significantly different between groups. Pre-lunch - pre-breakfast glucose levels were significantly lower in patients taking L + GB than those taking G + G300 (P < 0.0001). The difference in the highest post-breakfast glucose level between groups (Δ = G + G300 - L + GB) was significantly correlated to 24-h mean glucose level (r = 0.40, P = 0.03).

CONCLUSIONS

Compared with L + GB, G + G300 decreases post-breakfast glucose level reducing rate of rise of that, nocturnal and 24-h glucose variability and level without causing hypoglycemia, and daily variance.

Comparison of baseline characteristics and clinical course in Japanese patients with type 2 diabetes among whom different types of oral hypoglycemic agents were chosen by diabetes specialists as initial monotherapy (JDDM 42)

Little is known about the relationships between patient factors and the antihyperglycemic agents that have been prescribed as initial therapy by diabetes specialists for patients with type 2 diabetes. Moreover, there has been little clarification of the subsequent usage patterns and related factors that influenced the continuation or discontinuation of the drug or the addition of another drug. To provide information on these issues, we evaluated the clinical characteristics of Japanese patients with type 2 diabetes for whom different types of oral hypoglycemic agents (i.e., either sulfonylureas, biguanides, or DPP-4 inhibitors (DPP-4Is)) were chosen as initial monotherapy by diabetes specialists and evaluated subsequent usage patterns.Prescription data on 3 different antidiabetic agents from December 2009 to March 2015 from diabetes specialists' patient registries were used to identify variables at baseline related to initial prescriptions; also, the addition of another hypoglycemic drug or discontinuation of the initial therapy was evaluated 1 year after the initial prescription. Analyzed were data on 2666 patients who received initial monotherapy with either a sulfonylurea (305 patients), biguanide (951 patients), or DPP-4I (1410 patients). Patients administered sulfonylureas were older, had a lower body mass index (BMI), longer duration of diabetes, and worse glycemic control than recipients of biguanides. Use of biguanides was related to younger age, short duration of diabetes, and obesity but was negatively associated with poor glycemic control. Older age but neither obesity nor poor glycemic control was associated with DPP-4Is. In all 3 groups a high HbA1c value was related to adding another hypoglycemic agent to the initial therapy. Moreover, adding another drug to a DPP-4I was related to a younger age and higher BMI.Patients' age, duration of diabetes, obesity, and glycemic control at baseline influenced the choice of hypoglycemic agents. Selection of a biguanide differs greatly from that of a sulfonylurea or DPP-4I with regard to age and obesity.

Delayed insulin secretion response during an OGTT is associated with an increased risk for incidence of diabetes in NGT subjects

AIMS

This study aimed to assess whether insulin secretion patterns during oral glucose tolerance tests (OGTTs) could predict future type 2 diabetes (T2D) in Chinese normal glucose tolerance (NGT) subjects.

METHODS

A total of 558 NGT, 419 newly diagnosed impaired glucose tolerance, and 694 newly diagnosed T2D patients were assessed. NGT subjects were grouped based on the time of peak insulin secretion during a 3h- OGTT; at 30min (InsP30), 60min (InsP60), 120min (InsP120), or 180min (InsP180), respectively. NGT subjects were followed up for an average duration of 5.58±1.08years. Beta-cell function was estimated by Stumvoll insulin secretion.

RESULTS

The InsP120 and InsP180 groups had lower Stumvoll first-phase insulin secretion levels compared with InsP30. At 5.58±1.08years, 25 (5.39%) NGT subjects had developed T2D. The cumulative incidence rate of diabetes was higher in the InsP120 and InsP180 groups (8.94%), compared with InsP30 (1.48%) (P<0.05). The adjusted relative risk for incident diabetes was 7.30 (95% CI: 1.53-34.72) times higher in the InsP120 and InsP180 groups.

CONCLUSIONS

NGT subjects with late insulin responses had defective early insulin secretion and were at higher risk of developing diabetes. Insulin secretion patterns could be a useful T2D predictor in the Chinese population.

Sustained Decrease of Early-Phase Insulin Secretion in Japanese Women with Gestational Diabetes Mellitus Who Developed Impaired Glucose Tolerance and Impaired Fasting Glucose Postpartum

OBJECTIVE

The aim of this study was to compare glucose intolerance in the antenatal and the postpartum periods using a 75-g oral glucose tolerance test (OGTT) in the Japanese women with gestational diabetes mellitus (GDM) using a retrospective design.

PATIENTS AND METHODS

Data were obtained from 85 Japanese women with GDM who delivered from April 2011 through April 2015 and who underwent an OGTT 6–14 weeks postpartum. The women were divided into two groups based on the results of the postpartum OGTT: one group with normal glucose tolerance (NGT) and the other with impaired glucose tolerance (IGT) as well as impaired fasting glucose (IFG). We analyzed the associations between postpartum IGT–IFG and various factors.

RESULTS

Antenatally, a significant difference was observed between the groups only in the 1-hour plasma glucose level of the 75-g OGTT. Postpartum results of plasma glucose level were significantly higher at 0.5, 1, and 2 hours in the IGT–IFG group than those in the NGT group. Moreover, a significant decrease in the levels of 0.5-hour immunoreactive insulin and insulinogenic index was observed in the IGT–IFG group compared to those in the NGT group. Homeostasis model assessment-insulin resistance and homeostasis model assessment β-cell function of both groups were found to significantly decrease in the postpartum period; however, there was no significant change in the insulinogenic index of either group.

CONCLUSIONS

Our study clearly showed that the postpartum IGT and IFG levels of Japanese women with GDM are affected by impaired early-phase insulin secretion; however, insulin resistance promptly improves.

Comparison of clinical characteristics in patients with type 2 diabetes among whom different antihyperglycemic agents were prescribed as monotherapy or combination therapy by diabetes specialists

AIMS/INTRODUCTION

We compared clinical characteristics in patients with type 2 diabetes for whom different antihyperglycemic agents were prescribed as monotherapy or combination therapy by diabetes specialists in Japan.

MATERIALS AND METHODS

Prescription data for 2005, 2008 and 2011 from diabetes specialists' patient registries identified variables related to prescription of different antihyperglycemic agents.

RESULTS

A total of 33,251 prescriptions in 2005, 25,119 in 2008 and 20,631 in 2011 were analyzed. Prescribing insulin was related to younger age, long duration of diabetes and glycated hemoglobin (HbA1c) ≥8.0%, but was negatively associated with obesity. Prescribing sulfonylureas was related to older age and long duration of diabetes, but not to obesity. Use of biguanides was related to younger age, short duration of diabetes and obesity, but was negatively associated with HbA1c ≥8.0%. A short duration of diabetes and HbA1c ≥8.0% were associated with use of a DPP-4 inhibitor, but not with obesity. Prescribing GLP-1 receptor agonists was related to younger age, obesity and HbA1c ≥8.0%. Odds ratios for each antihyperglycemic combination therapy were determined based on the characteristics of each included antihyperglycemic agent.

CONCLUSIONS

These results could be expected to reflect in part the consensus of diabetes specialists, and might provide guidance regarding pharmacotherapy in the clinical setting.

Comparison of sitagliptin with nateglinide on postprandial glucose and related hormones in drug-naïve Japanese patients with type 2 diabetes mellitus: A pilot study

AIMS/INTRODUCTION

Dipeptidyl peptidase-4 inhibitors and glinides are effective in reducing postprandial hyperglycemia. However, little information is available on the comparative effects of the two drugs on the levels of postprandial glucose. The aim of the present study was to compare the effects of sitagliptin and nateglinide on meal tolerance tests in drug-naïve patients with type 2 diabetes mellitus.

MATERIALS AND METHODS

The study participants were 19 patients with type 2 diabetes mellitus, which was inadequately controlled by diet and exercise. An open-label, prospective, cross-over trial was carried out to compare the effects of single-dose sitagliptin and nateglinide on the postprandial glucose level and its related hormones during meal tests.

RESULTS

The change in area under the curve (AUC) of glucose from 0 to 180 min (AUC0-180 min) during the meal test by nateglinide was similar to that by sitagliptin. As expected, the change in active glucagon like peptide-1 was significantly higher after a single-dose of sitagliptin than nateglinide. Then, insulin secretion relative to glucose elevation (ISG) (ΔISG0-180 min: ΔAUC0-180 min insulin/AUC0-180 min glucose) was significantly enhanced by nateglinide compared with sitagliptin. Conversely, glucagon level (ΔAUC0-180 min glucagon) was increased by administration of nateglinide, whereas the glucagon level was reduced by administration of sitagliptin.

CONCLUSIONS

The effects of sitagliptin on postprandial glucose levels were similar to those of nateglinide in drug-naïve type 2 diabetes patients. However, the induced changes in insulin, active glucagon-like peptide-1 and glucagon during meal loading suggest that reduction of postprandial hyperglycemia was achieved by the unique effect of each drug.

An inverse U-shaped association of late and peak insulin levels during an oral glucose load with glucose intolerance in a Japanese population: a cross-sectional study

The current study investigated the association of post-load insulin levels with glucose tolerance in a Japanese population. A total of 1450 Japanese employees who underwent a 75-g oral glucose tolerance test (OGTT) were included. Glucose tolerance was assessed by 120-min glucose levels during a 75-g OGTT. A penalized cubic regression spline model analysis revealed that the 60- and 120-min insulin levels, but not 0- or 30-min insulin levels, had an inverse U-shaped relationship to the 120-min glucose level. Furthermore, peak insulin level followed an inverse U shape in relation to the 120-min glucose level, whereas the peak of insulin appeared at a later point in time as the 120-min glucose level increased. These associations were similarly observed in both obese and non-obese subgroups, although obesity was associated with higher insulin levels. Peak insulin levels also demonstrated an inverse U shape in association with 0-min glucose levels and indices of β cell function, assessed by the disposition index and the β-cell function index. In conclusion, peak insulin levels followed an inverse U shape in relation to glucose intolerance in a Japanese population, whereas the impairment of glucose tolerance was associated with a delay in the time to reach peak insulin levels.

Effect of insulin glargine on endogenous insulin secretion and beta-cell function in Japanese type 2 diabetic patients using oral antidiabetic drugs

The aim of the present study was to evaluate the effect of insulin glargine (Gla) (as part of basal-supported oral therapy) on endogenous insulin secretion and beta-cell function in type 2 diabetic patients. In 33 insulin-naive patients showing poor glycemic control on treatment with sulfonylurea (SU)-based OADs without DPP4 inhibitors, once-daily injection of Gla was added without changing OADs, and the dose of Gla was titrated to attain a fasting plasma glucose (FPG) <110 mg/dL over 24 weeks. Morning meal tests were done at baseline, 12 weeks and 24 weeks. FPG and 2-hour plasma glucose (2HPG) and serum C-peptide (FCPR and 2HCPR) were measured 3 times, while serum intact proinsulin (FPI and 2HPI) was measured at baseline and 24 weeks. Levels of FPG, FCPR, 2HPG, and HbA1c were significantly reduced from baseline at 24 weeks (176±52 to 117±27 mg/dL, p<0.01; 2.0±0.9 to 1.6±1.0 ng/mL, p<0.01; 257±53 to 202±27 mg/dL, p<0.01; and 8.4±0.9 to 7.3±0.6%, p<0.01, Mean±SD), but 2HCPR was unchanged. The patients were divided into two groups depending on whether FPG at 24 weeks was <110 mg/dL or not: attained group (n=15) and not attained group (n=18). The dose of Gla did not differ between the two groups, but the 2HPI/2HCPR ratio at 24 weeks showed a significant decrease from baseline in the attained group. Supplementation with Gla improved glycemic control and maintained intrinsic basal insulin secretion, without changing 2-hour postprandial secretion. Achieving good glycemic control with an FPG<110 mg/dL by adding Gla decreased the 2HPI/2HCPR ratio at 24 weeks.

Comparison of the hypoglycemic effect of sitagliptin versus the combination of mitiglinide and voglibose in drug-naïve Japanese patients with type 2 diabetes

OBJECTIVE

The postprandial glucose (PPG) level is reduced by α-GIs, glinides and DPP4Is through different pharmacological actions. The aim of this study was to compare the effect of sitagliptin (S) versus that of the combination of mitiglinide and voglibose (M+V) on markers of glycemic control.

RESEARCH DESIGN AND METHODS

A randomized cross-over trial was performed in 20 patients with drug-naïve type 2 diabetes. The patients were randomized to receive S (50 mg/day) or M+V (1 tablet 3 times daily). Treatment was continued for 8 weeks, after which they were switched to the other regimen and treated for another 8 weeks. At baseline, after the first regimen, and after the second regimen, a meal test was performed.

MAIN OUTCOME MEASURES

The markers of glycemic control were examined.

RESULTS

Reduction of glucose excursion was significantly greater with M+V than with S. HbA1c did not change with either regimen. However, 1,5-anhydroglucitol showed a significant increase from baseline with both regimens (7.9 ± 4.3 μg/ml at baseline vs. 10.6 ± 5.5 with S, p < 0.05 and 15.1 ± 6.2 with M+V, p < 0.01). Compared with baseline, glycoalbumin was significantly reduced by M+V, but not S (19.6 ± 2.9% at baseline vs. 17.3 ± 3.8% with M+V, p < 0.05).

CONCLUSION

M+V achieved better control of PPG excursion than S.

Daily rice intake strongly influences the incidence of metabolic syndrome in Japanese men aged 40-59 years

OBJECTIVES

The first objective of this study was to classify men aged 40-74 yrs with metabolic syndrome (MetS) according to daily rice intake, and the second was to investigate physical measurements, physiological examinations, blood biochemical assays, intake of food other than rice and lifestyle and environmental factors in the study group.

METHODS

We analyzed data from 6095 men aged 40-74 yrs who had undergone full medical examinations. The men were classified into 3 age groups: (1) 40-49 yrs, (2) 50-59 yrs, and (3) 60-74 yrs. The men were classified further into 3 groups according to daily rice intake: group 1 (≤300 g), group 2 (300-450 g), and group 3 (≥450 g). The relationship between daily rice intake and the following factors was analyzed in the three age brackets: (1) physical measurements including waist circumference, (2) physiological measurements, (3) serum biochemical indices, (4) whether or not the person was taking medication for hypertension, diabetes mellitus or serum lipid abnormalities, (5) lifestyle, and (6) consumption of foods other than rice.

RESULTS

Daily rice intake was related strongly to the occurrence of MetS in all three age brackets. Multiple logistic regression analysis showed (1) a significant increase in the odds ratio for MetS (1.461 times) for group 3 compared with group 1 in men aged 40-49 yrs and (2) a significant increase in the odds ratio for MetS (1.501 times) for group 3 compared with group 1 in men aged 50-59 yrs. However, there was no significant difference in the odds ratio for MetS among rice intake groups in the 60-74 age bracket.

CONCLUSION

In men aged 40-59 yrs, daily rice intake strongly influenced the incidence of MetS, whereas in men aged 60-74 yrs, there was no relationship between daily rice intake and MetS.

Incidence of type 2 diabetes by HbA1c and OGTT: the Isfahan Diabetes Prevention Study

The aim of this study was to estimate the incidence of type 2 diabetes using newly proposed hemoglobin A(1C) (HbA(1c)) and current oral glucose tolerance test (OGTT) definition in an Iranian non-diabetic population. A total of 923 non-diabetic first-degree relatives (FDRs) of patients with type 2 diabetes 30-70 years old in 2003-2005 were followed through 2009 for the occurrence of type 2 diabetes. At baseline and through follow-ups, participants underwent a standard 75 g 2-h OGTT and HbA(1c) measurements. Prediction of progression to type 2 diabetes by OGTT-defined or HbA(1c)-defined diabetes was assessed with area under the receiver operating characteristic (ROC) curves based upon measurement of fasting plasma glucose, 2-h post-load glucose values, and HbA(1c). The prevalence of type 2 diabetes was 9.2% (95% CI: 8.2, 10.2) by OGTT-defined diabetes and 7.9% (95% CI: 6.9, 9.0) by HbA(1c) ≥ 6.5. The incidence of type 2 diabetes was 2.0% (95% CI: 1.6, 2.4) (1.8% men and 2.1% women) per year by the current OGTT definition, whereas the incidence rates were 1.7% (95% CI: 1.3, 2.0) (1.6% men and 1.7% women) per year by HbA(1c) ≥ 6.5%. Of those diagnosed with type 2 diabetes by OGTT, 69.6% had HbA(1c) <6.5% and therefore would not have been classified as having type 2 diabetes. The incidence and prevalence of diabetes using newly proposed HbA(1c) threshold in this FDRs of patients with type 2 diabetes were slightly lower than using current OGTT definition.

Hyperosmolar hyperglycemic state in advanced amyotrophic lateral sclerosis

Our objective was to describe cases of hyperosmolar hyperglycemic state (HHS) in advanced amyotrophic lateral sclerosis (ALS) patients and discuss its pathophysiology. Five ventilator-dependent patients with ALS, with no previous history of diabetes, showed development of marked hyperglycemia (plasma glucose levels of 755-1544 mg/dl) after preceding infectious episodes. All patients had severe generalized muscle wasting and tetraplegia. The initial manifestations of HHS were fever, drowsiness, or polyuria. Hydration and intravenous insulin therapy were markedly effective, resulting in favorable recovery without the necessity of chronic medication for hyperglycemia in all cases. Seventy-five grams oral glucose tolerance tests performed via feeding tubes in two patients after the successful treatment of HHS revealed increased insulin resistance and diminished early-phase insulin secretion with preserved total insulin secretion. In conclusion, a marked loss of skeletal muscle, the largest glucose consumer of the human body, with background abnormality of early-phase insulin secretion, might be a causative factor of HHS in advanced ALS.

The potential impact of using glycated haemoglobin as the preferred diagnostic tool for detecting Type 2 diabetes mellitus

AIMS

There are calls to simplify the diagnosis of Type 2 diabetes mellitus (T2DM) to reduce the burden of undiagnosed disease. Glycated haemoglobin (HbA(1c)) is therefore being considered as a preferred diagnostic tool to replace the need for an oral glucose tolerance test (OGTT), considered by many as cumbersome and inconvenient. The aim of this study was to examine the potential impact of the preferred use of HbA(1c) as a diagnostic tool on the prevalence and phenotype of T2DM.

METHODS

Analysis of the Leicester Ethnic Atherosclerosis and Diabetes Risk (LEADER) cohort for previously undiagnosed individuals between 40 and 75 years of age who had OGTT, repeated if within the diabetes range, and HbA(1c) results. We compared the prevalence and phenotype of subjects with T2DM based on either HbA(1c)> or =6.5% or OGTT using 1999 World Health Organization criteria.

RESULTS

From the total population of 8696, we detected 291 (3.3%) with T2DM from using an OGTT, and 502 (5.8%) had HbA(1c)> or =6.5%. Of those diagnosed with T2DM by OGTT, 93 (1.2%) had HbA(1c) <6.5% and therefore would not have been classified as having T2DM using proposed criteria. Using HbA(1c) criteria resulted in 304 (3.5%) additional cases of T2DM, approximately doubling the prevalence. Of these 304 additional people, 172 (56.7%) had impaired glucose tolerance/impaired fasting glycaemia according to 1999 World Health Organization criteria. Using HbA(1c) criteria there was an increase of 2.2- and 1.4-fold in south Asians and white Europeans detected, respectively.

CONCLUSIONS

Within this multi-ethnic cohort, we found that introducing HbA(1c)> or =6.5% as the preferred diagnostic test to diagnose T2DM significantly increased numbers detected with T2DM; however, some people were no longer detected as having T2DM.

Effects of low intensity exercise therapy on early phase insulin secretion in overweight subjects with impaired glucose tolerance and type 2 diabetes mellitus

This study was designed to evaluate effects of exercise therapy on early phase insulin secretion in overweight subjects with impaired glucose tolerance (IGT) and type 2 diabetes mellitus (DM). The subjects consisted of overweight subjects with normal glucose tolerance (NGT, n=10), IGT (n=10) and DM (n=10) (age: 51.1+/-8.2, 56.3+/-8.8 and 58.5+/-6.2 years, respectively). All of these patients performed exercise therapy at lactate threshold intensity for 12 weeks. Before intervention, area under the glucose curve (AUC(PG)) was higher in DM, IGT and NGT groups, and area under the insulin curve (AUC(IRI)) and the early phase insulin secretion as calculated by insulinogenic index was higher in the NGT group than in either the IGT or DM groups (p<0.05). After exercise therapy, the insulin sensitivity, AUC(PG) and AUC(IRI) improved in three groups (p<0.05, respectively). The insulinogenic index increased in IGT and DM groups (p<0.05, respectively), but the changes in the insulinogenic index showed no significant differences between IGT and DM groups. These results suggest that the ss-cell function in subjects with IGT and DM could therefore improve after exercise therapy. Moreover, AUC(PG), AUC(IRI) and insulin sensitivity were also improved no relation to NGT, IGT and DM.

Efficacy of pioglitazone on type 2 diabetic patients with hemodialysis

AIMS

Unfortunately, growing number of type 2 diabetic hemodialysis (HD) patients with insulin resistance are now being diagnosed in Japan. Worse still, PPARgammaagonists such as pioglitazone are now contraindicated in diabetic HD patients in Japan. In this study we evaluated the efficacy of pioglitazone in diabetics on HD.

METHODS

Following a 12-week baseline period, we enrolled a study population of poorly controlled diabetic HD patients who had mean hemoglobin A1c (HbA1c) levels greater than 6.5% at baseline and who were not receiving insulin injection therapy. The patients were administered pioglitazone 15mg daily with their morning meal for the first 4 weeks. Subsequently, the doses were titrated by dose-doubling to a maximum of 30mg/day if no adverse effects appeared. The efficacy was determined by monitoring glycemic control (plasma glucose and HbA1c), and insulin resistance (plasma immunoreactive insulin (IRI) and homeostasis model assessment for insulin resistance (HOMA-R)). Safety and tolerance were determined by monitoring clinical and laboratory parameters.

RESULTS

Pioglitazone was effective in reducing plasma glucose and HbA1c from the baseline levels from week 4 after the commencement of treatment. The agent was also effective in reducing triglycerides. Plasma IRI and HOMA-R, two parameters of insulin resistance, decreased significantly at 4 weeks, and the decreases continued for 24 weeks. Systolic and diastolic blood pressures were statistically lower at 8 weeks. No serious adverse effects such as hypoglycemia, liver impairment, or rhabdomyolysis were observed in any of the patients.

CONCLUSIONS

Pioglitazone was effective in the treatment of diabetics on dialysis therapy. Pioglitazone might have the potential to reduce the number of type 2 diabetics on HD who ultimately require insulin injection therapy.

Altered expression of glucagon-like peptide-1 and dipeptidyl peptidase IV in patients with HCV-related glucose intolerance

BACKGROUND AND AIM

The pathogenesis of hepatitis C virus (HCV)-associated glucose intolerance remains unclear. Glucagon-like peptide-1 (GLP-1), a gut hormone, synthesizes hepatic glycogen and is inactivated by dipeptidyl peptidase IV (DPPIV). The aims of this study were to investigate the alterations in the expression of GLP-1 and DPPIV in HCV-associated glucose intolerance.

METHODS

We enrolled patients with HCV- or hepatitis B virus (HBV)-related liver disease (n = 94 and 37, respectively), patients with inflammatory bowel disease (IBD; n = 14) as disease controls, and healthy controls (n = 48). The serum or tissue GLP-1 and DPPIV expression levels were determined by enzyme immunoassay, immunoblotting, or immunostaining. The hepatic glycogen content was assayed by periodic acid-Schiff staining.

RESULTS

The serum GLP-1 levels were significantly decreased in the HCV group (4.9 +/- 0.3 ng/mL) than those in the controls (7.5 +/- 0.6 ng/mL), the HBV group (7.0 +/- 0.5 ng/mL), or the IBD group (10.8 +/- 1.0 ng/mL, P < 0.01). Although the ileum GLP-1 expression was not significantly different between the controls and the HCV group, the DPPIV expression was significantly increased in the ileum, liver, and serum in the HCV group. Hepatic glycogen content was decreased to a greater extent in the HCV group than that in the HBV group (127.5 +/- 5.3 vs 187.7 +/- 6.6 arbitrary units; n = 19, P < 0.01).

CONCLUSION

We demonstrated the altered expressions of GLP-1 and DPPIV in patients with HCV-associated glucose intolerance. Since hepatic glycogen synthesis, a GLP-1 action, was impaired, the altered expressions of GLP-1 and DPPIV may be involved in the development of HCV-associated glucose intolerance.

Deterioration of glycemic control during octreotide LAR treatment in an acromegalic Japanese patient with type 2 diabetes mellitus

We report a case showing deterioration of glycemic control during octreotide long-acting release (LAR) treatment in an acromegalic Japanese patient with type 2 diabetes mellitus. The patient did not show much improvement of insulin sensitivity (QUICKI; 0.33 before treatment, 0.35 during octreotide LAR treatment), and showed a significant reduction in early insulin secretion (insulinogenic index; 0.28 before treatment, 0.08 during octreotide LAR treatment) on 75 g oral glucose tolerance test (75gOGTT), despite decreases in GH and IGF-I levels during the course of octreotide LAR treatment. Postoperatively, both insulin sensitivity and early insulin secretion on 75gOGTT were improved (QUICKI 0.59, insulinogenic index 0.35). There are some reports that insulinogenic index is lower in most Japanese patients with type 2 diabetes mellitus and that early insulin secretions are significantly suppressed after administration of octreotide LAR. Although the influence of octreotide LAR on glucose metabolism varies among individuals, it is necessary to manage the deterioration of glucose tolerance during octreotide LAR treatment in acromegalic Japanese patients with decreased insulinogenic index.

Characteristics of Japanese subjects who progress from normal to impaired glucose tolerance. Longitudinal study excluding changes in body weight

In this retrospective longitudinal study, we focused on the clinical characteristics of Japanese individuals with recent onset impaired glucose tolerance (IGT) who have been followed up for insulin secretory function and 75-gram oral glucose tolerance test (OGTT) for more than 3 years annually before they progressed from normal glucose tolerance (NGT) to IGT. Subjects whose body weight did not show significant change for the period were selected and labeled as either NGT (no change in OGTT over 3 years) or IGT (progressors from NGT to IGT) groups (n = 24, each). We compared the basal biochemical data and response of plasma glucose and serum insulin after OGTT of the two groups. In the IGT progressors, significant increase of plasma glucose at 30 to 120 minutes during OGTT and significant decrease of HDL-cholesterol were observed since 3 years before onset of IGT. In addition to increase of serum glucose and decrease of HDL-cholesterol, serum insulin at 120 minutes during OGTT were significantly and remarkably high at onset and 3 years before onset of IGT. Plasma glucose at 30-120 minutes and serum insulin level at 120 minutes after glucose load are potentially significant predictors of progression from NGT to IGT even in subjects who do not show increase of body weight.

Gender differences in association of plasma adiponectin with obesity reflect resultant insulin resistance in non-diabetic Japanese patients with schizophrenia

Adipose tissues poorly produce adiponectin in the population with increased body fat mass and diabetes mellitus. It was investigated whether hypoadiponectinemia is associated with obesity and insulin resistance in patients with chronically medicated schizophrenia. A cross-sectional study was designed for 73 non-diabetic Japanese patients with schizophrenia. The patients aged <70 years with body mass index (BMI) > or =18.5 were selected. Anthropometrics and blood parameters including fat-derived cytokines were measured, and then the BMI and homeostasis model assessment-insulin resistance (HOMA-IR) was calculated. The variables were compared between the non-obesity (BMI, 18.5-24.9) and obesity (> or = 25.0) groups, and between genders. Plasma adiponectin negatively correlated with BMI (r = -0.554, P < 0.0003) and HOMA-IR (r = -0.380, P = 0.007) in men, but not in women. The obesity group in men, as compared with the non-obesity group, showed significantly lower plasma adiponectin (P = 0.008) and higher HOMA-IR (P < 0.05), but not in women. Plasma leptin showed a significant positive correlation with BMI (r = 0.604, P < 0.0001 in men; r = 0.763, P < 0.0001 in women) and HOMA-IR (r = 0.618, P < 0.0001 in men; r = 0.679, P < 0.0001 in women). The mean plasma leptin in the obesity group was significantly higher than that in the non-obesity group (P < 0.01 in men; P < 0.01 in women). In contrast to plasma leptin, plasma adiponectin showed gender difference in relation to BMI and HOMA-IR.

Diabetes in Japan

In this article, we introduce the increasing prevalence of type 2 diabetes in the Japanese population and discuss the reasons for such an explosive increase. Diabetes has been brought into prominence in Japan by enhanced insulin resistance, through the change of lifestyle against the background of fragile beta-cell function and thrifty genotypes.

Development and Progression of Atherosclerotic Disease in Relation to Insulin Resistance and Hyperinsulinemia

It is unclear whether the role of insulin resistance in the development of atherosclerotic cardiovascular disease is similar in populations in which the incidence of atherosclerotic diseases significantly differs from that in Western countries. The aim of this study was to determine the relationship between insulin resistance and the development of cardiovascular disease in the Japanese population. We conducted 75 g-oral glucose tolerance tests (OGTTs) on 1,928 inhabitants of two towns in Hokkaido, Japan. Subjects using antihypertensive agents and known diabetic patients were excluded from the study. Data from the remaining 1,227 subjects (540 males and 687 females; mean age 56.0 +/- 10.8 years) were used for the analysis, and 1,051 subjects were seen in a follow-up care setting for a period of 8 years. The presence of insulin resistance was defined according to the guidelines reported our previous study: insulin levels of 64.0 mU/l or higher 2 h after the 75 g-OGTT. The insulin-resistant (IR) group had several risk factors such as hypertension, diabetes, treated or untreated hypercholesterolemia, hypertriglyceridemia, low high-density-lipoprotein (HDL) cholesterol levels, and obesity. During the follow-up period of 8 years, the incidence of coronary artery disease, which was adjusted for age, body mass index, sex, systolic blood pressure, fasting plasma glucose, total cholesterol, triglyceride, and HDL cholesterol was significantly (3.2 times) higher in the IR group than in the insulin non-resistant group. The results suggested that insulin resistance is an independent risk factor for coronary artery disease in Japanese subjects, as has also been demonstrated in the case of individuals in Europe and USA.

Thr54 allele of the FABP2 gene affects resting metabolic rate and visceral obesity

We investigated the relationship between Ala54Thr variant allele of the fatty acid-binding protein 2 (FABP2) gene (Ala54Thr) and development of obesity in Japanese obese women. FABP2 genotypes were determined with a fluorescent allele-specific DNA primer assay system. Body weight, waist and hip circumference, amounts of visceral and subcutaneous white adipose tissue measured by computed tomography (CT) were compared between subjects with Thr allele and without Thr allele before and after the diet and exercise therapy in 80 Japanese obese women. The frequency of the Thr54 allele did not differ between obese and control subjects (0.388 versus 0.329, respectively). In subjects with Ala/Thr and Thr/Thr genotype, adjusted resting metabolic rate (RMR) was significantly lower than the subjects with Ala/Ala genotype. Subjects with the Thr54 allele showed significantly greater waist circumference after diet and exercise therapy than subjects with Ala/Ala genotype. They also demonstrated greater body weight at 20 years of age compared to subjects with Ala/Ala genotype. In conclusion, Thr54 allele of FABP2 has associations with lower adjusted resting metabolic rate, resistance in reducing visceral white adipose tissue (WAT) and early onset of obesity in Japanese obese women.

Prevalence and concomitants of glucose intolerance in European obese children and adolescents

OBJECTIVE

The worldwide increase in the prevalence of childhood obesity is reaching epidemic proportions and is associated with a dramatic rise in cases of type 2 diabetes. The prevalence of glucose intolerance and its determinants and the relation of cardiovascular risk factors with levels of glycemia and degree of obesity were studied in grossly obese children of European origin.

RESEARCH DESIGN AND METHODS

A total of 710 grossly obese Italian children (SD score [SDS] of BMI 3.8 +/- 0.7) aged 6-18 years, including 345 male subjects, underwent an oral glucose tolerance test. Insulin resistance and insulin secretion were estimated using the homeostasis model assessment for insulin resistance and the insulinogenic index, respectively. Fibrinogen, C-reactive protein, lipids, and uric acid were measured. The 2-h postload glucose and degree of obesity, calculated as the SDS of weight/height(2), were used as dependent variables.

RESULTS

The prevalence of glucose intolerance was 4.5%. Insulin resistance (P < 0.0001), impaired insulin secretion (P < 0.0001), and diastolic blood pressure (BP) (P < 0.05) were significantly and independently related to 2-h postload glucose values. The degree of obesity did not relate to insulin resistance but was independently correlated with inflammatory proteins, uric acid, and systolic BP, variables that were often abnormal in this population.

CONCLUSIONS

In these grossly obese children, both insulin resistance and impaired insulin secretion contribute to the elevation of glycemia, and the degree of obesity is related to cardiovascular risk factors independently of insulin resistance.

Fasting criteria for screening: test properties and agreement with glucose tolerance

The objective of this study was to characterise test properties and agreement for fasting glucose cut-offs used for screening diabetes in Indigenous Australian communities, across a range of diabetes prevalence. The oral glucose tolerance test (OGTT) was administered to adult volunteers (n=3249) for community-based diabetes screening in isolated settlements (n=25). Two-hour post-load glucose concentration was the 'gold standard' against which test properties were characterised for fasting plasma glucose cut-offs at concentrations of > or = 7.0 mmol/l (ADA criterion) and > or = 7.8 mmol/l (WHO criterion). Test sensitivity (95% CI) was greater for the ADA (72.5%, 67.4-77.1%) versus the WHO criterion (61.5%, 56.1-66.6%). Specificity was high (>98%) using either criterion. The post-test likelihood of diabetes, given a population prevalence of 14.8%, was 89.1% using the ADA criterion, and 94.9% using the WHO criterion. The ADA criterion gave better agreement than did the WHO criterion for diabetes prevalence > or = 8.6%, and the probability of false results was lower using the ADA criterion, when diabetes prevalence was > or = 12.8%. According to the ADA criterion most individuals ascribed false negative results were aged > or = 35 years, overweight/obese, or had impaired fasting glucose. The fasting glucose criterion of 7.0 mmol/l was superior to 7.8 mmol/l in screening for diabetes.

Diabetes trends in Japan

The prevalence of diabetes is increasing in Japan, and it is estimated that more than 12 million Japanese people are hyperglycemic. This high prevalence is most likely the result of a complex interplay between genetic and environmental factors specific to Japan. The lifestyle and diet of the Japanese population have changed significantly since the end of World War II. In general, the Japanese have become more sedentary and they consume more fat than in the past. Among Japanese men, these changes have been associated with a steadily increasing body mass index (BMI), a well-known risk factor for the development of insulin resistance, impaired glucose tolerance, and diabetes. Genetic characteristics common to many Japanese may also contribute to their higher prevalence of diabetes. The Japanese have a higher prevalence of polymorphisms for at least three genes that code for proteins thought to play key roles in lipid and glucose metabolism: the beta 3-adrenergic receptor, the peroxisome proliferator-activated receptor gamma, and calpain-10. The interaction between changes in lifestyle and the 'thrifty' genotype characteristic of many Japanese people may play a significant role in the increasing prevalence of diabetes and associated cardiovascular risk in this population.

Using HbA(1c) to improve efficacy of the american diabetes association fasting plasma glucose criterion in screening for new type 2 diabetes in American Indians: the strong heart study

OBJECTIVE

To find an optimal critical line in the fasting plasma glucose (FPG)-HbA(1c) plane for identifying diabetes in participants with impaired fasting glucose (IFG) and thereby improve the efficacy of using FPG alone in diabetes screening among American Indians.

RESEARCH DESIGN AND METHODS

We used FPG, 2-h postload glucose (2hPG), and HbA(1c) measured in the 2,389 American Indians (aged 45-74 years, without diabetes treatment or prior history of diabetes) in the Strong Heart Study (SHS) baseline (second) examination. Participants were classified as having diabetes if they had either FPG > or =126 mg/dl or 2hPG > or =200 mg/dl, as having IFG if they had 110 < or = FPG < 126 mg/dl, and as having normal fasting glucose (NFG) if they had FPG <110, according to the American Diabetes Association (ADA) definition. Logistic regression models were used for identifying diabetes (2hPG > or =200 mg/dl) in IFG participants. The areas under the receiver operating characteristic (ROC) curves generated by different logistic regression models were evaluated and compared to select the best model. A utility function based on the best model and the cost-to-benefit ratio was used to find the optimal critical line. The data from the second examination were used to study the effect of the time interval between the successive diabetes screenings on both the FPG criterion and the optimal critical line.

RESULTS

A total of 37% of all subjects with new diabetes at baseline and 55.2% of those in the second exam had 2hPG > or =200 but FPG <126. There was a very large portion of IFG participants with diabetes (19.3 and 22.9% in the baseline and second exam, respectively). Among the areas under the ROC curves, the area generated by the logistic regression model on FPG plus HbA(1c) is the largest and is significantly larger than that based on FPG (P = 0.0008). For a cost-to-benefit ratio of 0.23888, the optimal critical line that has the highest utility is: 0.89 x HbA(1c) + 0.11 x FPG = 17.92. Those IFG participants whose FPG and HbA(1c) were above or on the line were referred to take an oral glucose tolerance test (OGTT) to diagnose diabetes. The optimal critical line is lower if a successive diabetes screening will be conducted 4 years after the previous screening.

CONCLUSIONS

FPG > or =126 and 2hPG > or =200, as suggested by the ADA, are used independently to define diabetes. The FPG level is easy to obtain, and using FPG alone is suggested for diabetes screening. It is difficult to get physicians and patients to perform an OGTT to get a 2hPG level because of the many drawbacks of the OGTT, especially in those patients who already have FPG <126. It is also impractical to conduct an OGTT for everyone in a diabetes screening. Our data show that 37% of all subjects with new diabetes in the SHS baseline exam and 55.2% of those in the second exam have 2hPG > or =200 but FPG <126. These cases of diabetes cannot be detected if FPG is used alone in a diabetes screening. Therefore, although the small portion of diabetes in the NFG group (4.7% in the baseline and 6.9% in the second exam) may be ignored, those cases of diabetes among IFG participants ( approximately 20% in our data) need further consideration in a diabetes screening. It may be worthwhile for those IFG participants identified by the optimal critical line to take an OGTT. The optimal critical line and time interval between successive diabetes screenings need further study.

Diagnosis of diabetes mellitus and intermediate glucose abnormalities in obese patients based on ADA (1997) and WHO (1985) criteria

AIM

To assess the accuracy of the 1997 ADA criteria for diagnosing diabetes mellitus and related glucose disturbances in comparison with the reference WHO 1985 criteria in obese subjects.

PATIENTS AND METHODS

In 286 men and 881 women, 15-84 years of age, with obesity (body mass index (BMI) > or = 30 kg/m2), an oral glucose tolerance test (OGTT) was carried out according to WHO standard. Patients were classified into three categories of glucose tolerance using WHO 1985 (Normal Glucose Tolerance (NGT), Impaired Glucose Tolerance (IGT) and Diabetes Mellitus (DM)) and ADA (Normal Fasting Glucose (NFG), Impaired Fasting Glucose (IFG) and DM) criteria. Prevalence of each category was compared and agreement between the two classifications was assessed. The relation between fasting plasma glucose value and diabetes, as diagnosed by WHO 1985 criteria, was studied using various regression models, cumulative frequency curves, Finch method and ROC curve.

RESULTS

Compared with WHO 1985, ADA criteria strongly underestimated the prevalence rate of diabetes (3.7% vs. 10.6%) and intermediate glucose abnormalities (6.0% vs. 22.4%). Agreement between the two classifications was poor (kappa = 0.23). Moreover, many patients defined as glucose-intolerant by the WHO 1985 criteria were shifted to a more favourable metabolic status by ADA criteria. Thus, ADA criteria failed to detect 69% of WHO diabetic patients and 89% with IGT were considered as normal. According to the method, cut-off value of fasting blood glucose for detecting WHO 1985-diagnosed diabetes varied widely, from 5.3 to 6.3 mmol/l and none was satisfactory because of poor sensitivity and positive predictive value.

CONCLUSION

The ADA criteria do not appear to be a good substitute for those of the WHO 1985 at identifying diabetes and intermediate glucose abnormalities in an obese population. Since it appears impossible to determine a reliable cut-off value for fasting blood glucose to identify diabetic obese subjects with sufficient sensitivity, our results justify the retention of the OGTT in clinical practice or for epidemiological studies.

Decreased insulin secretion and dyslipidemia coexist in subjects with impaired fasting glucose

We examined the fasting plasma glucose (FPG) levels at which the compensatory mechanism of pancreatic beta cells could act and dyslipidemia would occur in Japanese subjects. A 75 g oral glucose tolerance test (OGTT) was performed on 8923 subjects. The relationship between FPG and immunoreactive insulin (IRI) was analyzed. The mean Sigma IRI (sum of IRI during OGTT) level formed an inverted U-shaped curve with a peak level at FPG of 110-130 mg/dl. The mean IRI level 30 min after glucose administration (as a marker of initial insulin secretion) began to decrease at an FPG level of approximately 100 mg/dl. The mean triglyceride level increased linearly with the elevation of the FPG level at FPG levels of 80-120 mg/dl. The mean high-density lipoprotein-cholesterol level decreased linearly with increasing FPG at FPG levels of 80-110 mg/dl. In Japanese, total insulin secretion during OGTT was affected at FPG levels >110-130 mg/dl. Moreover, subjects with FPG levels >110 mg/dl showed decreased initial insulin secretion and dyslipidemia. These results may indicate the necessity of intervention in individuals with impaired fasting glucose.

Usefulness of stable HbA(1c) for supportive marker to diagnose diabetes mellitus in Japanese subjects

To evaluate the adequacy and usefulness of the stable glycated hemoglobin (HbA(1c)) value of 6.5% suggested by the Japan Diabetic Society in 1999 for supportive diagnostic marker of diabetes, we assessed the sensitivity and specificity of an HbA(1c) value of 6.5% in patients who were newly diagnosed by the 75 g oral glucose tolerance test (75g-OGTT). A total of 866 Japanese subjects underwent the 75g-OGTT and HbA(1c) measurement (normal range: 4.3-5.8%). They were divided into three groups [normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and diabetes mellitus (DM)], using the WHO criteria, since no subject with impaired fasting glycemia (IFG) was observed. The cut-off value of HbA(1c) separating DM from NGT or DM from IGT on cumulative distribution curve analysis was 5.9% (sensitivity 0.76 and specificity 0.86) and 5.9% (sensitivity 0.76 and specificity 0.77), respectively. The sensitivity of an HbA(1c) of 6.5% for separation of DM from NGT or IGT by the same analysis was 0.49 and 0.49, respectively. Similarly, the specificity for separation of DM from NGT or IGT was 0.98 and 0.98, respectively. These results mean that 49% of diabetic subjects show an HbA(1c)> or =6.5%, and 51% have an HbA(1c) less than 6.5%, while only 2% of NGT and IGT subjects have an HbA(1c)> or =6.5%, and 98% have a value less than 6.5%. Therefore, the sensitivity of an HbA(1c) value of 6.5% in separating DM from NGT or IGT is low, and thus 6.5% is too high value to use when screening for diabetes. However, the specificity is very high, so an HbA(1c) of 6.5% is a useful supportive marker to diagnose diabetes.

Assessment of beta-cell function during the oral glucose tolerance test by a minimal model of insulin secretion

OBJECTIVE

To characterise the performance of beta-cell during a standard oral glucose tolerance test (OGTT).

DESIGN

Fifty-six subjects were studied. A minimal analogic model of beta-cell secretion during the OGTT was applied to all OGTTs (see below). The amount of insulin secreted over 120' in response to oral glucose (OGTT-ISR; Insulin Units 120'-1 m-2 BSA) and an index of beta-cell secretory 'force' (beta-Index; pmol.min-2.m-2 BSA) were computed with the aid of the model. In protocol A, 10 healthy subjects underwent two repeat 75 g OGTT with frequent (every 10'-15') blood sampling for glucose and C-peptide to test the reproducibility of OGTT-ISR and beta-Index with a complete or a reduced data set. In protocol B, 7 healthy subjects underwent three OGTTs (50, 100 or 150 g), to test the stability of the beta-Index under different glucose loads. In protocol C, 29 subjects (15 with normal glucose tolerance, 7 with impaired glucose tolerance and 7 with newly diagnosed type 2 diabetes) underwent two repeat 75 g OGTT with reduced (every 30' for 120') blood sampling to compare the reproducibility and the discriminant ratio (DR) of OGTT-ISR and beta-index with the insulinogenic index (IG-Index: Delta Insulin 30' - Basal/Delta Glucose 30' - Basal). In protocol D, 20 subjects (14 with normal glucose tolerance, 5 with impaired glucose tolerance and 1 with newly-diagnosed type 2 diabetes) underwent a 75 g OGTT and an intravenous glucose tolerance test (IVGTT) on separate days to explore the relationships between acute (0'-10') insulin response (AIR) during the IVGTT and beta-index and OGTT-ISR during the OGTT.

RESULTS

In all protocols, the minimal analogic model of C-peptide secretion achieved a reasonable fit of the experimental data. In protocol A, a good reproducibility of both beta-index and OGTT-ISR was observed with both complete and reduced (every 30') data sets. In protocol B, increasing the oral glucose load caused progressive increases in OGTT-ISR (from 2.63 +/- 0.70 to 5.11 +/- 0.91 Units.120'-1.m-2 BSA; P < 0.01), but the beta-index stayed the same (4.14 +/- 0.35 vs. 4.29 +/- 0.30 vs. 4.30 +/- 0.33 pmol.min-2.m-2 BSA). In protocol C, both OGTT-ISR and beta-index had lower day-to-day CVs (17.6 +/- 2.2 and 12.4 +/- 2.4%, respectively) and higher DRs (2.57 and 1.74, respectively) than the IG-index (CV: 35.5 +/- 6.3%; DR: 0.934). OGTT-ISR was positively correlated to BMI (P < 0.03), whereas beta-index was inversely related to both fasting and 2 h plasma glucose (P < 0.01 for both). In protocol D, beta-index, but not OGTT-ISR, was significantly correlated to AIR (r = 0.542, P < 0.02).

CONCLUSIONS

Analogically modelling beta-cell function during the OGTT provides a simple, useful tool for the physiological assessment of beta-cell function.

HbA1c measurement improves the detection of type 2 diabetes in high-risk individuals with nondiagnostic levels of fasting plasma glucose: the Early Diabetes Intervention Program (EDIP)

OBJECTIVE

Whereas new diagnostic criteria based on a fasting plasma glucose (FPG) of > 126 mg/dl (7.8 mmol/l) have improved the detection of diabetes, multiple reports indicate that many people with diabetes diagnosed by 2-h oral glucose tolerance test (OGTT) glucose measurements > or = 11.1 mmol/l (200 mg/dl) would remain undiagnosed based on this FPG criteria. Thus, improved methods to detect diabetes are particularly needed for high-risk individuals. We evaluated whether the combination of FPG and HbA1c measurements enhanced detection of diabetes in those individuals at risk for diabetes with nondiagnostic or minimally elevated FPG.

RESEARCH DESIGN AND METHODS

We analyzed FPG, OGTT, and HbA1c data from 244 subjects screened for participation in the Early Diabetes Intervention Program (EDIP).

RESULTS

Of 244 high-risk subjects studied by FPG measurements and OGTT, 24% of the individuals with FPG levels of 5.5-6.0 mmol/l (100-109 mg/dl) had OGTT-diagnosed diabetes, and nearly 50% of the individuals with FPG levels of 6.1-6.9 mmol/l (110-125 mg/dl) had OGTT-diagnosed diabetes. In the subjects with OGTT-diagnosed diabetes and FPG levels between 5.5 and 8.0 mmol/l, detection of an elevated HbA1c (>6.1% or mean + 2 SDs) led to a substantial improvement in diagnostic sensitivity over the FPG threshold of 7.0 mmol/l (61 vs. 45%, respectively, P = 0.002). Concordant FPG levels > or = 7.0 mmol/l (currently recommended for diagnosis) occurred in only 19% of our cohort with type 2 diabetes.

CONCLUSIONS

Diagnostic criteria based on FPG criteria are relatively insensitive in the detection of early type 2 diabetes in at-risk subjects. HbA1c measurement improves the sensitivity of screening in high-risk individuals.

New ADA criteria in the Korean population: fasting blood glucose is not enough for diagnosis of mild diabetes especially in the elderly

BACKGROUND

To compare the 1997 American Diabetes Association (ADA) criteria with the 1985 World Health Organization (WHO) criteria in categorization of the diabetes diagnostic status of Koreans and to define clinical characteristics of subjects diagnosed differently by the two criteria.

METHODS

In 810 Korean subjects, we analyzed blood glucose and insulin response during 75 g oral glucose tolerance test (OGTT). According to current WHO criteria, the cutoff values of FPG which distinguish normal and IGT from diabetes were determined. Then the subjects were categorized according to both WHO and ADA criteria. The clinical characteristics of the subjects with different diagnostic categories by the two criteria were defined.

RESULTS

The FPG cut point distinguishing diabetes from IGT was 117 mg/dl, and from normal was 110 mg/dl. The overall agreement between the ADA criteria and the WHO criteria was moderate, as reflected in the kappa of 0.45. 141 of subjects categorized diabetes by WHO criteria were not diagnosed with ADA criteria. These discordant subjects were older in age and showed blunted early insulin response than concordant normal subjects.

CONCLUSION

These results suggest that mild diabetes by the WHO criteria, especially in the elderly, would not be diagnosed as diabetes by the ADA FPG criteria only. Thus, in a group at high risk for developing diabetes or in a relatively older age group, we should continue using the OGTT.

Genetic and environmental interaction in Japanese type 2 diabetics

In Japanese type 2 diabetes, which occupies more than 95%, it is an increasingly important problem as a life-style related disease. The total diabetic population is estimated as approximately 7 million with a prevalence of approximately 6%. Along with genetically low postprandial insulin secretion, they are found to be less tolerable to being overweight to develop insulin resistance. The body weight change in the prediabetic era consisting of 508 male patients treated on their diet alone was reviewed and it was found that a few kilograms of weight gain could be a cause of insulin resistance. Moreover, inactive aldehyde dehydrogenese 2 (ALDH2), which is common in Japanese, is found to be a factor in the development of hyperglycemia. In 163 diabetics, HbAlc of the inactive ALDH2 group was 8.1+/-1.3, while that of active ALDH2 was 7.5+/-0.9% (P<0.05) in a light, social drinking group. However, Japanese type 2 diabetes is also changing. In recent years, the data from a 75-g oral glucose tolerance test of 2121 clients showed that insulinogenic index of clients with impaired glucose tolerance was similar to that of a normal glucose tolerance group and that the area under the insulin curve (AUC) was high in younger diabetics. From a life-style modification perspective, the importance of body weight control by diet and exercise as well as refraining from excessive drinking should be emphasized.

Comparison of ADA and WHO screening methods for diabetes mellitus in obese patients. American Diabetes Association

AIMS

To compare the performance of fasting glycaemia (FG) and oral glucose tolerance testing (OGTT) in screening for diabetes mellitus in obese patients.

METHODS

A consecutive series of 528 (445 female, 83 male) obese (body mass index > 30 kg/m2) outpatients, aged 45.2 +/- 14.3 years, was studied with FG and OGTT. The association of categories of glucose tolerance (diabetes and impaired glucose tolerance (IGT)) and fasting glycaemia (diabetes and impaired fasting glucose (IFG)) with hypertension and hyperlipidaemia were also assessed.

RESULTS

Prevalence of diabetes and IGT were 20.1 and 22.9%, respectively. FG (> 7 mmol/l) had a sensitivity of 56.7%. Using FG > 6.1 mmol/l, and OGTT in those above the threshold, the sensitivity for diabetes would have been 89.6%, with a positive predictive value of 59.0%, but 68.8% of cases of IGT would not have been detected. Patients with impaired fasting glucose (FG of 6.1-7.0 mmol/l) showed lower insulin sensitivity and impaired beta cell function, and a weaker association to hypertriglyceridaemia, when compared to IGT.

CONCLUSION

FG > 7.0 mmol/l does not show a sufficient sensitivity for the screening of diabetes in obese patients. FG > 6. mmol/l has a satisfactory sensitivity for diabetes, but not for IGT. IFG has different pathophysiological features than IGT and cannot be assumed to have the same prognostic value of IGT.