Elevated triglyceride/high-density lipoprotein-cholesterol ratio as a risk factor for progression to prediabetes: a 5-year retrospective cohort study in Japan.

Purpose: The triglyceride-to-high-density lipoprotein-cholesterol (TG/HDL-C) ratio is considered an alternative marker for insulin resistance. This longitudinal retrospective study investigated the relationship between TG/HDL-C ratio and the risk of progression to prediabetes. Methods: We investigated 24,604 Japanese participants (14,609 men and 9,995 women) who underwent annual medical health checkups in 2017 (baseline) and 2022. All participants had no diabetes and prediabetes at baseline. No lipid-lowering medications were taken during the follow-up period. Participants were divided into four groups according to the quartiles of TG/HDL-C ratio at baseline. Multivariable-adjusted Cox regression analysis was conducted to examine hazard ratios (HRs) of progression to prediabetes. Receiver operating characteristic curves were used to determine the optimal cutoff value of TG/HDL-C ratio for prediction of prediabetes. Results: Compared with the lowest TG/HDL-C ratio quartile (Q1) group, the adjusted HRs (95% confidence intervals (CI)) of progression to prediabetes in the Q2, Q3, and Q4 groups, respectively, were 1.17 (0.92-1.47), 1.26 (1.01-1.56), and 1.77 (1.41-2.23) for men and 1.07 (0.60-1.11), 1.19 (1.08-1.29), and 1.58 (1.18-2.31) for women. For every 1 unit increase in TG/HDL-C ratio, the adjusted HRs (95% CI) for progression to prediabetes was 1.09 (1.04-1.13) in men and 1.10 (1.04-1.15) in women. The optimal TG/HDL-C ratio cutoffs were 1.71 and 0.97 in men and women, respectively, but the area under the curve was > 0.70 in both sexes. Conclusion: High TG/HDL-C ratio is a risk factor for progression to prediabetes in Japanese men and women, but it had low discriminative ability in predicting prediabetes risk. Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-023-01329-8.

Elevated serum uric acid is a risk factor for progression to prediabetes in Japanese women: A 5-year retrospective chort study.

AIMS/INTRODUCTION: The association between serum uric acid (SUA) levels and prediabetes risk remains poorly understood. The aim of this longitudinal retrospective study was to evaluate the association between SUA levels and prediabetes progression in Japanese individuals through sex-specific analysis. MATERIALS AND METHODS: We enrolled 20,743 participants (11,916 men and 8,827 women) who underwent annual medical health checkups in 2017 (baseline) and 2022. None of the participants had diabetes and prediabetes or were taking SUA-lowering medications at baseline. Participants were divided into four groups according to the quartiles of SUA levels at baseline. Multivariable-adjusted Cox regression analysis was conducted to examine the risk of prediabetes progression. In addition, multivariate restricted cubic spline analysis was conducted to investigate the dose-response risk. RESULTS: In women, compared with the lowest SUA quartile (Q1) group, the adjusted hazard ratios (95% confidence intervals) of prediabetes in the Q2, Q3, and Q4 groups were 1.03 (0.86-1.25), 1.41 (1.18-1.68), and 1.55 (1.30-1.84), respectively. However, in men, no significant association in the risk of prediabetes was found across quartiles of SUA. Furthermore, in women, restricted cubic spline analysis revealed the dose-response relationship between SUA and progression to prediabetes. CONCLUSIONS: The results indicate that elevated serum SUA levels might be positively and independently associated with an increased risk of progression to prediabetes in Japanese women.

Reappraisal of attenuated insulin sensitivity in the evolution of non-alcoholic fatty liver disease.

BACKGROUND/OBJECTIVES: It has been unknown if attenuated insulin sensitivity (Si) in non-alcoholic fatty liver disease (NAFLD) is a cause or a result. We examined the impact of attenuated Si on NAFLD evolution. SUBJECTS/METHODS: We observed 4856 NAFLD- and diabetes-free participants for a mean 2.9 years. Si was indexed by single point insulin sensitivity estimator (SPISE = [600 × HDL-c0.185]/[TG0.2 × BMI1.338]), correlating with 1/HOMA-IR in an independent cohort (n = 1537, Spearman rho = 0.519, P < 0.01). Fatty liver (FL) was diagnosed by ultrasonography and diabetes by fasting plasma glucose (FPG) ≥ 7 mmol/L and/or glycohemoglobin A1c ≥ 6.5%. Multinominal comparison was performed with incident FL (FLw/oDM, n = 486), diabetes (DMw/oFL, n = 171), and FL plus diabetes (FL/diabetes, n = 58) as targets; none of the above (n = 4,138) was the control. SPISE was taken as a predictor with adjustment for covariates. Trajectory of SPISE during the 5 years before development of each condition was also assessed. RESULTS: With SPISE tertile 3 (>10.06) as the reference, tertile 1 (<8.07) was related to incident FLw/oDM and FL/diabetes with OR (95% CI) 3.47 (2.60-4.63) and 1.78 (1.10-2.87), respectively, and tertile 2 (8.07-10.06) related to FLw/oDM with OR (95% CI) 1.38 (1.03-1.85). Low SPISE was not significantly related to incident diabetes. At -5 years, SPISE was 12% (P < 0.05) and 13% (P < 0.01) lower in those developed FLw/oDM and FL/diabetes, respectively, than the control. At year 0, SPISE in the two groups was 18% and 21% lower than the control, respectively (P < 0.01). CONCLUSIONS: Attenuation of Si indexed by SPISE was a risk factor for NAFLD.

Type 2 Diabetes: When Does It Start?

OBJECTIVE: We aimed to clarify the onset of diabetes. DESIGN: Data from 27,392 nondiabetic health examinees were retrospectively analyzed for a mean of 5.3 years. Trajectories of fasting plasma glucose (FPG), body mass index (BMI), and the single point insulin sensitivity (Si) estimator (SPISE), an index of Si, 10 years before diagnosis of prediabetes (PDM; n = 4781) or diabetes (n = 1061) were separately assessed by a mixed effects model. Diabetes and PDM were diagnosed by the American Diabetes Association definition on the basis of FPG and glycosylated hemoglobin A1c values. RESULTS: In individuals who developed diabetes, mean FPG and BMI were significantly higher (P < 0.01 each) and SPISE lower than those who did not at -10 years: FPG 101.5 mg/dL vs 94.5 mg/dL, BMI 24.0 kg/m2 vs 22.7 kg/m2, and SPISE 7.32 vs 8.34, P < 0.01 each. These measurements, in subjects who developed prediabetes, were slightly but definitely different from those who did not, already at -10 years: FPG 91.8 mg/dL vs 89.6 mg/dL, BMI 22.6 kg/m2 vs 22.1 kg/m2, and SPISE 8.44 vs 8.82, P < 0.01 each. In both cases, the differences were progressively greater toward year 0, the time of diabetes, or PDM diagnosis. CONCLUSIONS: FPG was significantly elevated in those who developed diabetes at least 10 years before diagnosis of diabetes, and this was also the case in those who developed PDM. Glucose dysregulation precedes diagnosis of diabetes at least for 20 years.

Association of Low Urine pH with Insulin Resistance in Non-Diabetic Japanese Subjects.

BACKGROUND: Epidemiology studies have revealed that patients with obesity, hyperglycemia, or hypertension are associated with a decreased urine pH. These metabolic disorders are related to insulin resistance; however, the association between urine pH and insulin resistance remains unclear. METHODS: To evaluate this association while controlling for covariates, the present study was conducted in 1084 non-diabetic Japanese subjects undergoing health examination. Fasting urine pH was analyzed using an automated urine dipstick analyzer. The subjects were divided into five groups according to urine pH: those with pH <5.5, 5.5, 6.0, 6.5, and >6.5. Insulin resistance was determined using the homeostatic model assessment of insulin resistance (HOMA-IR) and divided into three categories: lower, middle, and higher tertiles of HOMA-IR. Analysis of covariance and multivariate logistic regression analysis were used to control confounding factors including serum uric acid. RESULTS: Analysis of covariance showed an increase in the mean HOMA-IR from 1.26, 1.46, 1.69, and 1.75 to 1.89 with a decrease in urine pH (p<0.001). Subjects with urine pH ≤5.5 had a significantly higher HOMA-IR than those with urine pH>6.5. Furthermore, multivariate logistic regression analysis showed that urine pH had an inverse and independent association with HOMA-IR. In subjects with urine pH 5.5 and <5.5, adjusted odds ratio (95% confidence interval) for the incidence of higher tertile of HOMA-IR was 1.34 (1.04-1.73) and 1.52 (1.09-2.13), respectively (reference, subjects with a urine pH>6.5). CONCLUSION: Insulin resistance is independently associated with a lower urine pH, possibly via lower formation of ammonium in the kidneys.

The utility of body mass index as an indicator for lipid abnormalities in non-fasting children.

BACKGROUND: Many studies have reported the association between body mass index (BMI) and fasting lipid profiles in children. However, little information exists about the screening of dyslipidemia in the non-fasted state. This study assessed whether BMI can predict non-fasting lipid abnormalities in children. METHODS: Using gender-separated analysis, 3895 boys and 3866 girls (aged 11-12 years) were investigated. Total cholesterol (TC), triglyceride (TG) and HDL-cholesterol (HDL-C) were measured, and non-HDL-C (=TC-[HDL-C]) was calculated. A BMI z-score was employed as the weight status. Gender-specific 95th percentiles of TC, TG and non-HDL-C were defined as "elevated", with the 5th percentiles of HDL-C defined as "reduced". RESULTS: TG and non-HDL-C were positively, and HDL-C was negatively correlated with the BMI z-score in both genders. Both obese (2

Corrigendum to "Optimal Hemoglobin A1c Levels for Screening of Diabetes and Prediabetes in the Japanese Population".

[This corrects the article DOI: 10.1155/2015/932057.].

Reduced Serum Phosphorus Levels Were Associated with Metabolic Syndrome in Men But Not in Women: A Cross-Sectional Study among the Japanese Population.

BACKGROUND: Reduced serum phosphorus (SP) levels are reported to be associated with insulin resistance and metabolic syndrome (MetS). However, there have been a few gender-specific studies although SP levels are substantially different between men and women. METHODS: This is a cross-sectional study. A total of 16,041 subjects (9,076 men and 6,965 women) were analyzed. The subjects were divided into 3 groups of gender-specific tertiles based on phosphorus levels: the lowest (T1), middle (T2), and the highest (T3). RESULTS: SP levels were significantly lower in subjects with MetS than in those without MetS in men but not in women. Waist circumference and fasting plasma glucose were negatively and high-density lipoprotein cholesterol was positively correlated with SP levels both in men and women. Blood pressure (BP) and triglycerides (TG) were negatively correlated with SP levels in men, while they were positively correlated with SP levels in women. Lower SP levels were associated with the prevalence of MetS in men (T1; 19.9%, T2; 16.9%, and T3; 14.3%; p < 0.001) but not in women (T1; 14.1%, T2; 16.6%, and T3; 15.3%; p = 0.282). CONCLUSION: BP and TG were unexpectedly positively correlated with SP levels in women. Reduced SP levels were associated with MetS in men but not in women.

Postchallenge hyperglycemia in subjects with low body weight: implication for small glucose volume.

A hypothesis that postchallenge hyperglycemia in subjects with low body weight (BW) may be due, in part, to small glucose volume (GV) was tested. We studied 11,411 nondiabetic subjects with a mean BW of 63.3 kg; 5,282 of them were followed for a mean of 5.3 yr. In another group of 1,537 nondiabetic subjects, insulin sensitivity, secretion, and a product of the two (index of whole body insulin action) were determined. Corrected 2 h-plasma glucose (2hPGcorr) during a 75-g oral glucose tolerance test in subjects with BW ≤ 59 kg was calculated as 2hPGcorr = δPG2h · ECW/[16.1 (males) or 15.3 (females)] + fasting PG (FPG), where δPG2h is plasma glucose increment in 2 h; ECW is extracellular water (surrogate of GV); FPG is fasting plasma glucose; and 16.1 and 15.3 are ECW of men and women, respectively, with BW = 59 kg. Multivariate analyses for BW with adjustment for age, sex, and percent body fat were undertaken. BW was, across its entire range, positively correlated with FPG (P < 0.01). Whereas BW was correlated with 2hPG and δPG in a skewed J-shape, with inflections at around 60 kg (P for nonlinearity < 0.01 for each). Nonetheless, in those with BW ≤ 59 kg, insulin sensitivity, secretion, and action were unattenuated, and incident diabetes was less compared with heavier counterparts. BW was linearly correlated with 2hPGcorr, i.e., the J-shape correlation was mitigated by the correction. In conclusion, postchallenge hyperglycemia in low BW subjects is in part due to small GV rather than impaired glucose metabolism.

Fasting Single-Spot Urine pH Is Associated with Metabolic Syndrome in the Japanese Population.

OBJECTIVE: To investigate the relationship between urine pH and metabolic syndrome (MetS) and its components, while controlling for covariates. SUBJECTS AND METHODS: This cross-sectional study was conducted on 5,430 Japanese subjects (4,691 without MetS; 739 with MetS) undergoing health assessments. Partial correlation analysis and analysis of covariance were used for controlling confounding parameters (age, gender, levels of serum uric acid and high-sensitivity C-reactive protein, estimated glomerular filtration rate, and smoking and drinking status). Using multiple logistic regression analyses, adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for MetS incidence were calculated across urine pH categories. Path analysis was used to determine the relationship between MetS and urine pH. RESULTS: Subjects with MetS had significantly lower urine pH (5.9 ± 0.7) than those without MetS (6.0 ± 0.7) (p < 0.001). Partial correlation analysis showed that systolic and diastolic blood pressure, and triglyceride and fasting plasma glucose levels were negatively correlated with urine pH, while high-density lipoprotein cholesterol was positively correlated with urine pH. Analysis of covariance indicated that urine pH decreased with an increasing number of metabolic abnormalities. Adjusted ORs (95% CI) for the presence of MetS in subjects with urine pH 5.5-6.0 and pH <5.5 were 1.34 (1.04-1.73) and 1.52 (1.09-2.13), respectively (reference: subjects with a urine pH >6.0). CONCLUSION: The MetS and its components were independently associated with lower urine pH.

Investigation of the relationship between hemoglobin and serum iron levels and early-phase insulin secretion in non-diabetic subjects.

AIMS: Recent biological and epidemiological studies have found that insulin resistance is linked to iron overload. However, little is known about the association between hemoglobin and/or serum iron levels and pancreatic ß-cell function. In this gender-separated cross-sectional study, we aimed to investigate the association of hemoglobin and serum iron levels with early-phase insulin secretion in non-diabetic subjects. METHODS: A total of 804 non-diabetic Japanese subjects (482 males and 322 females) aged over 30 years old were enrolled in the study. Early-phase insulin secretion was estimated using the insulinogenic index (IGI [ΔInsulin(30-0 min)/ΔGlucose(30-0 min)]) during a 75-g oral glucose tolerance test. RESULTS: Simple linear regression analysis showed that IGI negatively correlated with hemoglobin levels in male but not in female subjects. However, IGI did not correlate with serum iron levels in either gender. Multivariate linear regression analysis in male subjects revealed that hemoglobin levels were predictors of IGI, responsible for 3.0 % of IGI variation (P = 0.008). The association was independent of age, BMI, fasting glucose and insulin levels, and lipid profiles. In non-diabetic Japanese males, hemoglobin levels significantly and negatively correlated with early-phase insulin secretion. CONCLUSIONS: Our finding suggests that elevated hemoglobin levels may have a gender-specific impact on ß-cell function and could be an independent predictor of ß-cell dysfunction.

The association of maternal ABO blood group with gestational diabetes mellitus in Japanese pregnant women.

AIMS: To investigated the association between the ABO blood group and gestational diabetes mellitus (GDM). MATERIALS AND METHODS: A retrospective case-control study was conducted using data from 5424 Japanese pregnancies. GDM screening was performed in the first trimester using a casual blood glucose test and in the second trimester using a 50-g glucose challenge test. If the screening was positive, a 75-g oral glucose tolerance test was performed for a GDM diagnosis, which was defined according to the International Association of Diabetes and Pregnancy Study Groups. Logistic regression was used to obtain the odds ratio (OR) and 95% confidence interval (CI) adjusted for traditional risk factors. RESULTS: Women with the A blood group (adjusted OR: 0.34, 95% CI: 0.19-0.63), B (adjusted OR: 0.35, 95% CI: 0.18-0.68), or O (adjusted OR: 0.39, 95% CI: 0.21-0.74) were at decreased risk of GDM compared with those with group AB. Women with the AB group were associated with increased risk of GDM as compared with those with A, B, or O (adjusted OR: 2.73, 95% CI: 1.64-4.57). CONCLUSION: ABO blood groups are associated with GDM, and group AB was a risk factor for GDM in Japanese population.

Optimal Hemoglobin A1c Levels for Screening of Diabetes and Prediabetes in the Japanese Population.

The aim of this study was to evaluate the utility of hemoglobin A1c (HbA1c) to identify individuals with diabetes and prediabetes in the Japanese population. A total of 1372 individuals without known diabetes were selected for this study. A 75 g oral glucose tolerance test (OGTT) was used to diagnose diabetes and prediabetes. The ability of HbA1c to detect diabetes and prediabetes was investigated using receiver operating characteristic (ROC) analysis. The kappa (κ) coefficient was used to test the agreement between HbA1c categorization and OGTT-based diagnosis. ROC analysis demonstrated that HbA1c was a good test to identify diabetes and prediabetes, with areas under the curve of 0.918 and 0.714, respectively. Optimal HbA1c cutoffs for diagnosing diabetes and prediabetes were 6.0% (sensitivity 83.7%, specificity 87.6%) and 5.7% (sensitivity 60.6%, specificity 72.1%), respectively, although the cutoff for prediabetes showed low accuracy (67.6%) and a high false-negative rate (39.4%). Agreement between HbA1c categorization and OGTT-based diagnosis was low in diabetes (κ = 0.399) and prediabetes (κ = 0.324). In Japanese subjects, the HbA1c cutoff of 6.0% had appropriate sensitivity and specificity for diabetes screening, whereas the cutoff of 5.7% had modest sensitivity and specificity in identifying prediabetes. Thus, HbA1c may be inadequate as a screening tool for prediabetes.

Beneficial Effects of Vildagliptin on Metabolic Parameters in Patients with Type 2 Diabetes.

Blood pressure and lipid profile are important determinants of cardiovascular risk in patients with type 2 diabetes mellitus (T2DM). To identify the pleiotropic effects of vildagliptin other than blood glucose lowering effect, a retrospective study was conducted in 128 patients with T2DM treated with vildagliptin 50 mg twice daily. The patients were separated into two groups: patients who were initiated with vildagliptin as monotherapy or add-on therapy (add-on group, n = 66) and patients who were switched from sitagliptin 100 mg once daily to vildagliptin (switching group, n = 62). Hemoglobin A1c (HbA1c), body mass index (BMI), systolic/diastolic blood pressure, lipid profiles, and uric acid (UA) at 3, 6, and 12 months of vildagliptin therapy were compared with those at baseline in each group. At baseline, there were no significant differences in HbA1c, BMI, blood pressures, lipid profiles, and UA levels between the two groups. After vildagliptin initiation, HbA1c decreased significantly but BMI and blood pressure did not change in both groups. Only in the add-on group, total cholesterol and low density lipoprotein cholesterol decreased significantly from baseline to 3, 6, and 12 months. On the other hand, triglyceride and high-density lipoprotein cholesterol did not change in both groups. Serum UA levels decreased only in the switching group from baseline to 3, 6, and 12 months. These results indicate that vildagliptin add-on treatment may have beneficial effects on lipid profiles, and switching from sitagliptin to vildagliptin reduces UA in patients with T2DM; these are important findings linked to the beneficial effects of vildagliptin on lipid and UA metabolisms in the treatment of T2DM.

The relation between CA 19-9 level and early-phase insulin secretion in normoglycemic and prediabetic subjects.

BACKGROUND: Carbohydrate antigen (CA) 19-9 is used as a clinical tumor marker of pancreatic cancer; recent studies report that CA 19-9 is also associated with changes in blood glucose levels. The aim of the present study was to investigate the relationship between serum CA 19-9 levels and early-phase insulin secretion in nondiabetic individuals. METHODS: We enrolled 269 normoglycemic participants and 172 prediabetic participants who had undergone the 75-g oral glucose tolerance test during their annual health examination. Insulin secretion was estimated using the disposition index (DI) [(Δinsulin(0-30 min)/Δglucose(0-30 min) × (1/HOMA-IR)], which is an adjusted measure of relationship between ß-cell sensitivity and insulin sensitivity. RESULTS: Serum CA 19-9 level was significantly higher in the prediabetic participants than in the normoglycemic participants. Simple linear regression analysis showed a negative correlation between CA 19-9 levels and DI for all participants and prediabetic participants (r = -0.126, p = 0.009, and r = -0.189, p = 0.002, respectively). However, in the normoglycemic participants, CA 19-9 levels did not correlate with DI. For all participants, and prediabetic subjects, multivariate linear regression analysis revealed that serum CA 19-9 levels were one of the independent predictors of DI (adjusted ß = -0.098, p = 0.025, and adjusted ß = -0.177, p = 0.004, respectively). CONCLUSIONS: Serum CA 19-9 levels significantly correlate with early-phase insulin secretion in the prediabetic individuals. Our results indicate that CA 19-9 may be involved in the endocrine function of pancreas.

Adult-onset Still's disease with disseminated intravascular coagulation and hemophagocytic syndrome: a case report.

BACKGROUND: Adult-onset Still's disease is a rare inflammatory condition of unknown origin characterized by high spiking fever, arthralgia, arthritis, myalgia, salmon-colored evanescent rash, and hepatosplenomegaly. The diagnosis of adult-onset Still's disease requires the exclusion of other possible disorders because it lacks specific clinical and histopathological findings. Adult-onset Still's disease rarely become fatal due to visceral involvements such as disseminated intravascular coagulation. CASE PRESENTATION: A 22-year-old Chinese female presented to our medical center with high spiking fever for one week, myalgia for two weeks, and arthralgia and pink maculopapular rash for four weeks. She developed disseminated intravascular coagulation on the fourth day after admission. There was no other explanation for the fever and rash, including infection, malignancy, and collagenosis. Together, the high spiking fever, salmon-colored rash, splenomegaly, and excess hepatic enzyme, indicated adult-onset Still's disease based on the Yamaguchi criteria. Therefore, prednisolone therapy was initiated. The combination of nafamostat mesilate and prednisolone therapies caused a rapid reduction in the fever and rash. The inflammatory markers decreased immediately, and disseminated intravascular coagulation improved. Her symptoms resolved with low-dose prednisolone treatment, and she was monitored thereafter at our outpatient clinic. CONCLUSION: The previous use of nonsteroidal anti-inflammatory drugs could have caused disseminated intravascular coagulation in this patient with adult-onset Still's disease. We propose that physicians should consider the possibility of disseminated intravascular coagulation as a complication during the course of adult-onset Still's disease and suggest that prednisolone therapy should be initiated in the early stages of adult-onset Still's disease.

Impact of serum triglyceride and high density lipoprotein cholesterol levels on early-phase insulin secretion in normoglycemic and prediabetic subjects.

BACKGROUND: Increased triglycerides (TGs) and decreased high density lipoprotein cholesterol (HDL-C) levels are established as diabetic risks for nondiabetic subjects. The aim of this study was to investigate the relationship among TG, HDL-C, TG/HDL-C ratio, and early-phase insulin secretion in normoglycemic and prediabetic subjects. METHODS: We evaluated 663 Japanese subjects who underwent the 75-g oral glucose tolerance test. On the basis of these results, the subjects were divided into four groups: those with normal glucose tolerance (NGT; n=341), isolated impaired fasting glucose (i-IFG; n=211), isolated impaired glucose tolerance (i-IGT; n=71), and combined IFG and IGT (IFG+IGT; n=40). Insulin secretion was estimated by the insulinogenic index (IGI) (Δinsulin/Δglucose [30 to 0 minutes]) and disposition index (DI) (IGI/homeostasis model assessment of insulin resistance). RESULTS: In prediabetic subjects (i-IFG, i-IGT, and IFG+IGT), linear regression analyses revealed that IGI and DI were positively correlated with HDL-C levels. Moreover, in subjects with i-IGT and (IFG+IGT), but not with i-IFG, the indices of insulin secretion were negatively correlated with the log-transformed TG and TG/HDL-C ratio. In both the subjects with i-IGT, multivariate linear regression analyses revealed that DI was positively correlated with HDL-C and negatively with log-transformed TG and TG/HDL-C ratio. On the other hand, in subjects with NGT, there was no association between insulin secretion and lipid profiles. CONCLUSION: These results revealed that serum TG and HDL-C levels have different impacts on early-phase insulin secretion on the basis of their glucose tolerance status.

Correlation between mean platelet volume and blood glucose levels after oral glucose loading in normoglycemic and prediabetic Japanese subjects.

AIMS/INTRODUCTION: Mean platelet volume (MPV) reflects platelet activity, and high MPV is associated with thrombogenic activation and increased cardiovascular disease risk. Although a positive correlation between MPV and fasting plasma glucose (FPG) levels has been reported, the correlation between MPV and postprandial glucose levels remains unclear. The purpose of the present study was to evaluate the correlation between MPV and postprandial glucose levels in prediabetic and normoglycemic participants. MATERIALS AND METHODS: We evaluated 1,080 Japanese participants who underwent the 75-g oral glucose tolerance test (OGTT). Based on these results, the participants were divided into three groups: normal glucose tolerance group (NGT; n = 582), impaired fasting glucose group (IFG; n = 205) and impaired glucose tolerance group (IGT; n = 252). The relationship between MPV, FPG, and postchallenge glucose levels after 1 h (1 h-PG) and 2 h (2 h-PG) were analyzed. RESULTS: Bivariate correlation analyses showed a significant positive correlation between MPV and both FPG and 1 h-PG levels in the NGT group, as well as between MPV and 2 h-PG, total cholesterol, and low-density lipoprotein cholesterol in the IGT group. In contrast, no significant correlation was observed between MPV and postchallenge glucose levels in the IFG group. Multiple correlation analyses showed that FPG levels significantly correlated with MPV in the NGT and IGT groups. In addition, 1 h-PG and 2 h-PG levels correlated with MPV in the NTG and IGT groups, respectively. CONCLUSIONS: These results suggest a possible mechanism by which subjects with postprandial hyperglycemia might be at increased cardiovascular risk.

Serum triglyceride levels correlated with the rate of change in insulin secretion over two years in prediabetic subjects.

BACKGROUND/AIMS: Increased triglyceride (TG) and decreased high-density lipoprotein cholesterol (HDL-C) levels are considered risk factors for diabetes among prediabetic subjects. In this study, we retrospectively investigated the relationship between lipid profiles and the rate of change in early-phase insulin secretion in prediabetic subjects. METHODS: To evaluate insulin secretion, 50 prediabetic subjects underwent a 75-gram oral glucose tolerance test at the beginning of the study (baseline), and they were reexamined after a 2-year interval. The results were expressed as insulinogenic index (IGI) and disposition index (DI). RESULTS: The lipid profiles and indices of insulin secretion had not significantly changed over 2 years. However, Pearson's correlation analyses indicated that the rate of change in IGI and DI was negatively correlated with log-transformed baseline TG level, but not with baseline HDL-C level. Multiple linear regression analysis confirmed that the rate of change in IGI and DI was negatively correlated with the log-transformed baseline TG level (ß = -0.38, p = 0.006, and ß = -0.39, p = 0.006, respectively). CONCLUSIONS: Baseline TG level of prediabetic subjects appeared to be associated with rate of change in IGI and DI over a 2-year period, indicating that TG levels among prediabetic subjects should be carefully monitored.