Incidence of type 2 diabetes using proposed HbA1c diagnostic criteria in the european prospective investigation of cancer-norfolk cohort: implications for preventive strategies

Exploring aldose reductase inhibitors as promising therapeutic targets for diabetes-linked disabilities

Diabetes mellitus significantly increases mortality and morbidity rates due to complications like neuropathy and nephropathy. It also leads to retinopathy and cataract formation, which is a leading cause of vision disability. The polyol pathway emerges as a promising therapeutic target among the various pathways associated with diabetic complications. This review focuses on the development of natural and synthetic aldose reductase inhibitors (ARIs), along with recent discoveries in diabetic complication treatment. AR, pivotal in the polyol pathway converting glucose to sorbitol, plays a key role in secondary diabetes complications' pathophysiology. Understanding AR's function and structure lays the groundwork for improving ARIs to mitigate diabetic complications. New developments in ARIs open up exciting possibilities for treating diabetes-related complications. However, it is still challenging to get preclinical successes to clinical effectiveness because of things like differences in how the disease starts, drug specificity, and the complexity of the AR's structure. Addressing these challenges is crucial for developing targeted and efficient ARIs. Continued research into AR's structural features and specific ARIs is essential. Overcoming these challenges could revolutionize diabetic complication treatment, enhance patient outcomes, and reduce the global burden of diabetes-related mortality and morbidity.

Experimental study on physical exercise in diabetes: pathophysiology and therapeutic effects

Diabetes is a chronic disease. Some complications can be prevented, their effects can be slowed down.  Sedentary lifestyle increases the risk of obesity and consequently the predisposition to diabetes II. The article aimed to demonstrate the positive and negative effects of exercise on active and sedentary diabetics and on pathophysiology, evaluating the effects after 3 and 6 months. The study involved 90 participants, both male and female, with type II diabetes, aged 45, divided into two groups: Group A (n=50, sedentary) and Group B (n=40, active). We evaluated anthropometric parameters, blood chemistry values, which are fundamental for the transversal evaluation of the results. In group A improvements were less noticeable than group B. The most improved parameter is blood sugar, Glycemic values and BMI. Cholesterol and Hb1Ac decreased but more slowly than previous parameters. The expectations of the study were, not only in recognizing the therapeutic and preventive powers of exercise, but above all in choosing to program a motor protocol after a team work between diabetologist, sports doctor and kinesiologist and/ or personal trainer. Physical activity is an additional therapy to insulin.

Effect of physical activity and different exercise modalities on glycemic control in people with prediabetes: a systematic review and meta-analysis of randomized controlled trials

Background

Numerous studies have shown the beneficial effects of exercise on glycemic control in people with prediabetes. However, the most effective exercise modality for improving glycemic control remains unclear. We aimed to assess which exercise training modality is most effective in improving glycemic control in a population with prediabetes.

Methods

We conducted searches in Pubmed/MEDLINE, EMBASE, SPORTDiscus, Web of Science, PEDro, BVS, and the Cochrane Library from inception to June 2022. Included studies reported fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), and 2-hour postprandial (2hPP) levels and implemented an exercise program lasting at least 12 weeks in adults with prediabetes. We performed a direct meta-analysis using a random-effects model and a network meta-analysis. Cochran's Q statistic and the inconsistency I2 test were used to assess the heterogenicity between studies.

Results

Twenty trials were included, with 15 trials (comprising 775 participants with prediabetes) combined in the meta-analysis, and 13 in the network meta-analysis. The meta-analysis results did not show a statistically significant reduction in fasting plasma glucose (FPG) after aerobic training (AT) intervention compared to a control group (mean (95%CI) difference = -5.18 (-13.48; 3.12) mg/dL, Z=1.22, p=0.22). However, a difference of -7.25 (-13.79; -0.71) mg/dL, p=0.03, in FPG after interval training (IT) intervention was detected compared to a control group. After resistance training (RT) intervention, FPG was significantly lower -6.71 (-12.65,-0.77) mg/dL, Z=2.21, p=0.03, and HbA1c by -0.13 (-0.55, 0.29), p=0.54, compared to the control group. The impact of RT compared to no intervention on 2hPP was not statistically significant (p=0.26). The network meta-analysis did not show statistical significance. Most of the studies presented an unclear risk of bias, and a low and very low-quality of evidence. According to the GRADE criteria, the strength of the body of evidence was low.

Conclusion

Resistance training and IT had demonstrated benefits on glycemic indices, especially on FPG, in a population with prediabetes. Further studies with larger sample sizes and a more robust methodology that compare different types of exercise modalities, frequencies, and durations, are needed to establish a beneficial exercise intervention.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=370688, identifier CRD42022370688.

Glycated Haemoglobin (HbA1c) and Future Physical and Mental Functional Health in the European Prospective Investigation into Cancer (EPIC)-Norfolk Population-Based Study

Little is understood about the relationship between glycated haemoglobin and future functional health in the general population. In this work, we aimed to assess if glycaemic control is associated with future physical and mental functional health at 18-month follow-up in a UK general population, in those with and without diabetes. This work was a cross-sectional study. Between 1995 and 1997, participants of the European Prospective Investigation into Cancer, Norfolk, attended a health check including blood testing for haemoglobin A1c (HbA1c) and completed a health and lifestyle questionnaire. Eighteen months later, self-reported physical and mental functional health were assessed using short form-36 (SF-36). Outcomes of interest included physical and mental component summary (PCS and MCS, respectively) scores of the SF-36. A total of 7343 participants (56% women, mean (SD) 58.1 ± 9.5 years) were eligible to be included, of whom 167 had prevalent diabetes. In our linear regression analysis, a higher HbA1c (mmol/mol) was found to be associated with a poorer PCS score (coefficient -0.15 (p < 0.0001)) at follow-up. After adjustment for comorbid conditions, including obesity, this association was no longer statistically significant. A higher HbA1c (mmol/mol) was associated with a better MCS score at follow-up; this finding was significant when adjusted for comorbid conditions (coefficient 0.029 (p < 0.05)). Our findings suggest that the association between a higher HbA1c and poorer physical functional health is explained by a higher BMI and comorbidity status in a general population. While higher HbA1c was found to be associated with higher mental functional health at follow-up, the magnitude of this association was small. Healthy responder bias and unmeasured confounding variables may have influenced this result; thus, it should be interpreted with caution.

Identifying risk factors of developing type 2 diabetes from an adult population with initial prediabetes using a Bayesian network

Background

It is known that people with prediabetes increase their risk of developing type 2 diabetes (T2D), which constitutes a global public health concern, and it is associated with other diseases such as cardiovascular disease.

Methods

This study aimed to determine those factors with high influence in the development of T2D once prediabetes has been diagnosed, through a Bayesian network (BN), which can help to prevent T2D. Furthermore, the set of features with the strongest influences on T2D can be determined through the Markov blanket. A BN model for T2D was built from a dataset composed of 12 relevant features of the T2D domain, determining the dependencies and conditional independencies from empirical data in a multivariate context. The structure and parameters were learned with the bnlearn package in R language introducing prior knowledge. The Markov blanket was considered to find those features (variables) which increase the risk of T2D.

Results

The BN model established the different relationships among features (variables). Through inference, a high estimated probability value of T2D was obtained when the body mass index (BMI) was instantiated to obesity value, the glycosylated hemoglobin (HbA1c) to more than 6 value, the fatty liver index (FLI) to more than 60 value, physical activity (PA) to no state, and age to 48-62 state. The features increasing T2D in specific states (warning factors) were ranked.

Conclusion

The feasibility of BNs in epidemiological studies is shown, in particular, when data from T2D risk factors are considered. BNs allow us to order the features which influence the most the development of T2D. The proposed BN model might be used as a general tool for prevention, that is, to improve the prognosis.

Urine ketone bodies and adverse outcomes in patients with acute ischemic stroke or TIA

Background and aims

Urine ketone bodies have been considered as predictors of stroke in diabetic patients, however, the role of urine ketone bodies in the prognosis of stroke has not been investigated well. This study aimed to investigate the association between urine ketone bodies and adverse outcomes in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA).

Methods

This study enrolled 14 015 patients with AIS or TIA who screened for urine ketone bodies from the Third China National Stroke Registry. Status of urine ketone bodies were classified into negative, suspicious positive and positive. The outcomes were all-cause death and poor functional outcomes (modified Rankin Scale [mRS] 2-6/3-6) at 3 months and 1 year. Multivariable Cox proportional hazards regressions and logistic regressions were adopted to explore the associations.

Results

Participants with negative, suspicious positive and positive urine ketone bodies were 12979 (92.61%), 480 (3.42%) and 556 (3.97%). After multivariate adjustment, patients with positive urine ketone bodies had a higher risk of all-cause death (hazard ratio, 1.74; confidence interval [CI], 1.07-2.83), a higher proportion of mRS score 2-6 (Odds ratio [OR], 1.85; 95% CI, 1.51-2.27), mRS score 3-6 (OR, 2.00; 95% CI, 1.61-2.48) at 3 months, compared to those with negative urine ketone bodies. Significant associations persisted at 1 year. Furthermore, there was no significant interaction of diabetes status and alcohol use with urine ketone bodies.

Conclusions

Positive urine ketone bodies can independently predict all-cause death and poor functional outcomes in patients with AIS or TIA.

Choice of HbA1c threshold for identifying individuals at high risk of type 2 diabetes and implications for diabetes prevention programmes: a cohort study

BACKGROUND

Type 2 diabetes (T2D) is common and increasing in prevalence. It is possible to prevent or delay T2D using lifestyle intervention programmes. Entry to these programmes is usually determined by a measure of glycaemia in the 'intermediate' range. This paper investigated the relationship between HbA1c and future diabetes risk and determined the impact of varying thresholds to identify those at high risk of developing T2D.

METHODS

We studied 4227 participants without diabetes aged ≥ 40 years recruited to the Exeter 10,000 population cohort in South West England. HbA1c was measured at study recruitment with repeat HbA1c available as part of usual care. Absolute risk of developing diabetes within 5 years, defined by HbA1c ≥ 48 mmol/mol (6.5%), according to baseline HbA1c, was assessed by a flexible parametric survival model.

RESULTS

The overall absolute 5-year risk (95% CI) of developing T2D in the cohort was 4.2% (3.6, 4.8%). This rose to 7.1% (6.1, 8.2%) in the 56% (n = 2358/4224) of participants classified 'high-risk' with HbA1c ≥ 39 mmol/mol (5.7%; ADA criteria). Under IEC criteria, HbA1c ≥ 42 mmol/mol (6.0%), 22% (n = 929/4277) of the cohort was classified high-risk with 5-year risk 14.9% (12.6, 17.2%). Those with the highest HbA1c values (44-47 mmol/mol [6.2-6.4%]) had much higher 5-year risk, 26.4% (22.0, 30.5%) compared with 2.1% (1.5, 2.6%) for 39-41 mmol/mol (5.7-5.9%) and 7.0% (5.4, 8.6%) for 42-43 mmol/mol (6.0-6.1%). Changing the entry criterion to prevention programmes from 39 to 42 mmol/mol (5.7-6.0%) reduced the proportion classified high-risk by 61%, and increased the positive predictive value (PPV) from 5.8 to 12.4% with negligible impact on the negative predictive value (NPV), 99.6% to 99.1%. Increasing the threshold further, to 44 mmol/mol (6.2%), reduced those classified high-risk by 59%, and markedly increased the PPV from 12.4 to 23.2% and had little impact on the NPV (99.1% to 98.5%).

CONCLUSIONS

A large proportion of people are identified as high-risk using current thresholds. Increasing the risk threshold markedly reduces the number of people that would be classified as high-risk and entered into prevention programmes, although this must be balanced against cases missed. Raising the entry threshold would allow limited intervention opportunities to be focused on those most likely to develop T2D.

The Goto Kakizaki rat: Impact of age upon changes in cardiac and renal structure, function

BACKGROUND

Patients with diabetes are at a high risk for developing cardiac dysfunction in the absence of coronary artery disease or hypertension, a condition known as diabetic cardiomyopathy. Contributing to heart failure is the presence of diabetic kidney disease. The Goto-Kakizaki (GK) rat is a non-obese, non-hypertensive model of type 2 diabetes that, like humans, shares a susceptibility locus on chromosome 10. Herein, we perform a detailed analysis of cardio-renal remodeling and response to renin angiotensin system blockade in GK rats to ascertain the validity of this model for further insights into disease pathogenesis.

METHODS

Study 1: Male GK rats along with age matched Wistar control animals underwent longitudinal assessment of cardiac and renal function for 32 weeks (total age 48 weeks). Animals underwent regular echocardiography every 4 weeks and at sacrifice, early (~24 weeks) and late (~48 weeks) timepoints, along with pressure volume loop analysis. Histological and molecular characteristics were determined using standard techniques. Study 2: the effect of renin angiotensin system (RAS) blockade upon cardiac and renal function was assessed in GK rats. Finally, proteomic studies were conducted in vivo and in vitro to identify novel pathways involved in remodeling responses.

RESULTS

GK rats developed hyperglycaemia by 12 weeks of age (p<0.01 c/w Wistar controls). Echocardiographic assessment of cardiac function demonstrated preserved systolic function by 48 weeks of age. Invasive studies demonstrated left ventricular hypertrophy, pulmonary congestion and impaired diastolic function. Renal function was preserved with evidence of hyperfiltration. Cardiac histological analysis demonstrated myocyte hypertrophy (p<0.05) with evidence of significant interstitial fibrosis (p<0.05). RT qPCR demonstrated activation of the fetal gene program, consistent with cellular hypertrophy. RAS blockade resulted in a reduction blood pressure(P<0.05) cardiac interstitial fibrosis (p<0.05) and activation of fetal gene program. No significant change on either systolic or diastolic function was observed, along with minimal impact upon renal structure or function. Proteomic studies demonstrated significant changes in proteins involved in oxidative phosp4horylation, mitochondrial dysfunction, beta-oxidation, and PI3K/Akt signalling (all p<0.05). Further, similar changes were observed in both LV samples from GK rats and H9C2 cells incubated in high glucose media.

CONCLUSION

By 48 weeks of age, the diabetic GK rat demonstrates evidence of preserved systolic function and impaired relaxation, along with cardiac hypertrophy, in the presence of hyperfiltration and elevated protein excretion. These findings suggest the GK rat demonstrates some, but not all features of diabetes induced "cardiorenal" syndrome. This has implications for the use of this model to assess preclinical strategies to treat cardiorenal disease.

Influence of Ramadan Fasting on Hemoglobin A1C, Lipid Profile, and Body Mass Index among Type 2 Diabetic Patients in Najran City, Saudi Arabia

BACKGROUND: Saudi Arabia is known to have one of the highest prevalence of diabetes in the world. The impact of Ramadan fasting on the health of type 2 diabetic patients is an important issue that has not been adequately investigated. AIM: The current study was aimed at assessing the impact of Ramadan fasting on hemoglobin A1C (HbA1c), lipid profile, blood pressure, and body mass index (BMI) in adult Saudis with Type 2 diabetes residing in Najran city. METHODS: This is a descriptive cross-sectional study which enrolled 289 patients who chose to fast during the month of Ramadan and were attending the outpatient clinics of Najran University Hospital. Fasting blood samples were taken 1 month before and 1 month after Ramadan to determine glycated hemoglobin and fasting lipid profile (low-density lipoprotein [LDL], high-density lipoprotein [HDL], triglyceride [TG], and total cholesterol [TC]) and BMI was also calculated. Information regarding demographics and physical activity was obtained through a questionnaire. RESULTS: As many as 176 (60.9%) of the participants reported to be physically inactive during Ramadan. There was a statistically significant (p < 0.05) decrease in the mean percentage of HbA1c when comparing before Ramadan (9.85 ± 2.37%) with after Ramadan (7.65 ± 1.70%). Furthermore, statistically significant difference (p < 0.05) was detected in the mean concentrations of LDL before (3.39 ± 1.06 mmol/L) and after (2.40 ± 0.83 mmol/L) Ramadan. The mean concentration of TC (before = 5.98 ± 2.00 mmol/L; after = 4.05 ± 1.18 mmol/L) and TG (before = 2.97 ± 1.95 mmol/L; after = 2.65 ± 1.65 mmol/L) also reduced after Ramadan. The mean concentrations of HDL (before = 1.78 ± 0.74 mmol/L; after= 2.23 ± 0.23 mmol/L) increased after Ramadan. The mean BMI of the study participants (before = 28.30 ± 6.27; after = 27.43 ± 5.92) decreased slightly after Ramadan. The systolic blood pressure (SBP) (before= 128.10 ± 6.32; after, 123.09 ± 5.71) and diastolic blood pressure (DBP) (before = 81.21 ± 8.51; after = 79.83 ± 7.21) showed a slight reduction after Ramadan. CONCLUSIONS: Type 2 diabetic patients who performed Ramadan fasting displayed a lowering of HbA1c, LDL, TC, and TG, and increased HDL, but had small positive effects on body weight, BMI, as well as SBP and DBP. More studies are needed with a larger population in the future to assess the potential of Ramadan fasting as a therapeutic strategy for managing Type 2 diabetes.

The effect of referral to an open-group behavioural weight-management programme on the relative risk of normoglycaemia, non-diabetic hyperglycaemia and type 2 diabetes: Secondary analysis of the WRAP trial

AIM

To examine the impact of open-group behavioural weight-management programmes on the risk of diabetes among those with a body mass index (BMI) of ≥28 kg/m² and those with non-diabetic hyperglycaemia (NDH).

METHODS

This was a secondary analysis of data from the WRAP trial, in which participants (N = 1267; aged ≥18 years, BMI ≥ 28 kg/m² ) were randomized to brief intervention (BI; self-help booklet), a weight-management programme (WW; formerly Weight Watchers) for 12 weeks, or WW for 52 weeks. We used multinomial logistic regression to examine the effect of intervention group on the risk of hyperglycaemia and diabetes at 12 months in all participants with glycaemic status at both time points (N = 480; 38%) and those with NDH at baseline (N = 387; 31%). We used mixed effects models and linear fixed effects models to examine the effect of intervention group on body weight and HbA1c at 12 months in people with NDH.

RESULTS

There was a 61% relative reduction in the risk of NDH at the 12-month follow-up (12 weeks vs. BI: relative risk ratio [RRR] = 0.39 [95% CI 0.18, 0.87], P = .021; 52 weeks vs. BI: RRR = 0.38 [95% CI 0.17, 0.86], P = .020). For intervention effects on the risk of diabetes, confidence intervals were wide and overlapped 1 [12 weeks vs. BI: RRR = 0.49 [95% CI 0.12, 1.96], P = .312; 52 weeks vs. BI: RRR = 0.40 [95% CI 0.10, 1.63], P = .199). Participants with hyperglycaemia at baseline in the weight-management programme were more probable to have normoglycaemia at the 12-month follow-up [12-week programme vs. BI: RRR = 3.57 [95% CI 1.24, 10.29], P = .019; 52-week programme vs. BI: RRR = 4.14 [95% CI 1.42, 12.12], P = .009).

CONCLUSIONS

Open-group behavioural weight-management programmes can help to prevent the development of NDH in people with overweight and obesity and to normalize glycaemia in people with NDH.

Effects of Ginkgo biloba intake on cardiometabolic parameters in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials

Ginkgo biloba (GKB) may have a beneficial effect on cardiometabolic parameters in type 2 diabetes mellitus (T2DM), but the data is inconsistent. Therefore, the current systematic review and meta-analysis of clinical trials was conducted to assess the influence of GKB on cardiometabolic parameters in T2DM. Several online databases such as PubMed, Embase, Scopus, Web of Sciences, Google Scholar and Cochrane Library were systematically searched from inception up to September 2, 2019. Heterogeneity across included studies was assessed using the Cochran's Q statistic and I2 index. To pool weighted mean differences (WMDs) and the corresponding 95% confidence intervals (CIs) as summary effect size, we selected fixed or random-effects model according to the result of heterogeneity. Seven studies comprising 768 subjects were included in the present meta-analysis which resulted in a significant effect of GKB on hemoglobin A1c (HbA1c) (WMD = 0.26, 95% CI = [0.02, 0.50], p = .034) and serum HDL-cholesterol levels (WMD = 1.99, 95% CI = [0.19, 3.79], p = .030) with no significant publication bias. GKB can significantly modulate HbA1c and HDL-cholesterol levels. However, due to uncertainties related to the limited number of studies, it is too early to conclude whether GKB has any potential effects on the cardiometabolic factors in patients with T2DM or not.

Lifestyle and Progression to Type 2 Diabetes in a Cohort of Workers with Prediabetes

Background: People with prediabetes have an increased risk of developing type 2 diabetes (T2D). Few studies have evaluated the influence of lifestyle factors on the risk of progression to diabetes and reversion to normoglycemia. The aim of this study was to determine the incidence of T2D in a large cohort of workers with prediabetes, and to evaluate the influence of sociodemographic, clinical, metabolic, and lifestyle factors that affect the persistence of prediabetes and the progression to T2D. Methods: A cohort study of 27,844 adult workers (aged 20 to 65 years) from Spain who had prediabetes based on an occupational medical examination from 2012 to 2013. Prediabetes was defined as fasting plasma glucose (FPG) between 100 and 125 mg/dL. At the baseline evaluation, sociodemographic, anthropometric, metabolic, and lifestyle data were collected. At the 5-year follow-up, incident T2D was defined as an FPG of at least 126 mg/dL or initiation of an antidiabetic medication. Results: Among 235,995 initially screened workers, the prevalence of T2D was 14.19% (95% confidence interval (CI) 14.05 to 14.33) and the prevalence of prediabetes was 11.85% (95% CI 11.71 to 11.99). Follow-up data were available for 23,293 individuals with prediabetes. Among them, 36.08% (95% CI 35.46 to 36.70) returned to normoglycemia, 40.92% (95% CI 40.29 to 41.55) had persistent prediabetes, and 23.00% (95% CI 22.46 to 23.54) progressed to T2D. The risk for persistence of prediabetes and for progression to T2D increased with age, body mass index (BMI), triglyceride level, and less than 150 min/week of physical activity. An HbA1c level of 6% or greater was the strongest individual predictor of progression to T2D. Conclusions: Physical activity, diet, smoking, and BMI are modifiable factors that are associated with the persistence of prediabetes and the progression to T2D. The workplace is a feasible setting for the early detection of prediabetes and the promotion of lifestyles that can prevent progression to T2D.

Performance of Point-of-Care Testing Compared with the Standard Laboratory Diagnostic Test in the Measurement of HbA1c in Indonesian Diabetic and Nondiabetic Subjects

OBJECTIVE

This study is aimed at investigating if point-of-care testing for HbA1c (POCT-HbA1c) using the HemoCue® HbA1c 501 system could be an alternative method for diabetes screening and monitoring to replace the HbA1c measurement in a standard diagnostic laboratory.

DESIGN

This was a cross-sectional study to assess the agreement between POCT and a standard laboratory measurement method for determining the level of HbA1c. Setting and Participants. In total, 108 participants were recruited to participate in this study, consisting of 61 diabetics and 47 nondiabetics. The diabetic group comprised 37 females and 24 males, diagnosed with type 2 diabetes mellitus (DM) and undergoing diabetes treatment at several community health care centres in Bandung, West Java. The nondiabetic group consisted of 15 female and 32 male patients of several community health care centres and healthy volunteers. Sample Collection and Analysis. A venous blood sample was taken for routine HbA1c analysis by the diagnostic laboratory method. For the POCT-HbA1c, a blood sample was taken from the fingertip at the same time and analysed with the HemoCue® HbA1c 501 system. Outcome Measures. The HbA1c results of both methods were compared and analysed with a Bland-Altman agreement plot. The sensitivity and specificity of the POCT-HbA1c data were also compared with those of the standard diagnostic results.

RESULTS

Based on the Bland-Altman plot, the HbA1c level for 100 out of 108 (92.59%) subjects analysed by the POCT-HbA1c was within the range of the 95% limit of agreement. Compared with the standard diagnostic assay, the sensitivity of the POCT-HbA1c was 97.83% and its specificity was 77.42%.

CONCLUSIONS

The high sensitivity and accuracy of POCT-HbA1c indicate that it is a potential method for diabetes screening and monitoring to replace the routine diagnostic laboratory HbA1c measurement, especially when a rapid result is required.

Size and Shape of Associations of OGTT as Well as Mediating Effects on Adverse Pregnancy Outcomes Among Women With Gestational Diabetes Mellitus: Population-Based Study From Southern Han Chinese

Objective: To explore the size and shape association of OGTT values with adverse pregnancy complications among women with gestational diabetes mellitus (GDM) in Southern Han Chinese population and further analyze their mediating effects with maternal age in outcomes. Methods: 6,861 women with GDM were included in the study. Logistic regression was used to identify the correlations between OGTT values and adverse pregnancy outcomes of GDM. Restricted cubic spline nested logistic regression was conducted to investigate potential non-linear and linear associations. Mediating effect among maternal age, OGTT and adverse outcomes were explored. Results: Women with GDM had a mean age of 31.83, and 24.49% had advanced maternal age (≥35 years). In logistic regression with adjustment, compared with lower OGTT0 (<5.1 mmol/L), GDM patients with higher OGTT0 (≥5.1 mmol/L) exhibited 1.891 (95% CI: 1.441-2.298, P < 0.001), 1.284 (1.078-1.529, P = 0.005), 1.285 (1.065-1.550, P = 0.009), and 1.302 (1.067-1.590, P = 0.010) times increased risk of hypertensive disorders of pregnancy (HDP), preterm, neonatal hyperbilirubinemia, and macrosomia, respectively. GDM patients with higher OGTT1 (≥10 mmol/L) had only found to exhibited 1.473-fold (1.162-1.867, P = 0.001) increasing risk of HDP than those with lower OGTT1 (<10 mmol/L). No adverse outcome was identified to associate with higher OGTT2 (≥8.5 mmol/L). Linear relationships (non-linear P > 0.05) were observed between OGTT0 and HDP, preterm, neonatal hyperbilirubinemia, and macrosomia in both maternal age groups (<35 and ≥35 years). Non-linear associations of OGTT1 with incidence of HDP, preterm, and neonatal hyperbilirubinemia were detected in GDM patients younger than 35 years (non-linear P = 0.037, P = 0.049, P = 0.039, respectively), rising more steeply at higher values. Similar non-linearity was noted for OGTT2 with HDP in older patients. All OGTT values had significant mediating effects on some special complications caused by higher age. Conclusion: Higher fasting plasma glucose was more strongly linked to adverse pregnancy outcomes among GDM patients. Both linearity and Non-linearity of associations between glucose and complications should be taken into account. A careful reconsideration of GDM with hierarchical and individualized management according to OGTT is needed.

Gene-diet quality interactions on haemoglobin A1c and type 2 diabetes risk: The Airwave Health Monitoring Study

INTRODUCTION

Type 2 diabetes (T2D) is multifactorial involving lifestyle, environmental and genetic risk factors. This study aims to investigate the impact of genetic interactions with alcohol and diet quality on glycated haemoglobin A1c (HbA1c) independent of obesity, in a British population.

METHODS

Cross-sectional study of 14 089 white British participants from Airwave Health Monitoring Study and a subsample of 3733 participants with dietary data. A T2D genetic risk score (GRS) was constructed, and its interactions with diet on HbA1c were assessed.

RESULTS

GRS was associated with a higher HbA1c% (β = 0.03, P < 0.0001) and a higher risk of prediabetes (OR = 1.09, P < 0.0001) and T2D (OR = 1.14, P = 0.006). The genetic effect on HbA1c% was significantly higher in obese participants (β = 1.88, P interaction = 0.03). A high intake of wholegrain attenuated the effect on HbA1c% in high-risk individuals P interaction = 0.04.

CONCLUSION

The genetic effect on HbA1c was almost doubled in obese individuals, compared with those with a healthy weight, and independent of weight, there was a modest offset on HbA1c in high-genetic-risk individuals consuming a diet high in wholegrain. This supports the importance of a healthy diet high in wholegrains and along with maintaining a healthy weight in controlling HbA1c among high-genetic-risk groups.

Protective Effects of Aqueous Extract of Baillonella toxisperma Stem Bark on Dexamethasone-Induced Insulin Resistance in Rats

The aim of this study was to evaluate the effects of the aqueous extract of Baillonella toxisperma stem bark on dexamethasone-induced insulin resistance in rats. A quantitative phytochemical study was done on the aqueous extract of Baillonella toxisperma for the total phenol, flavonoid, and flavonol determination. Insulin resistance was induced by intraperitoneal injection of dexamethasone (1 mg/kg) for 8 days, one hour before oral administration of different treatments (extract at doses of 60, 120, and 240 mg/kg and metformin at 40 mg/kg). During the test, body weight and blood glucose level were evaluated on days 1 and 8. At the last day of treatment, the glucose tolerance test was performed in rats; after that, blood samples were collected for triglycerides, total cholesterol, LDL and HDL cholesterols, transaminases (ALT and AST), and total protein level determination. Organs (heart, liver, pancreas, and kidneys) were also collected for the relative organ weight determination. The results showed that the aqueous extract of B. toxisperma is rich in total phenols, flavonoids, and flavonols. This extract significantly reversed the metabolic alterations (lipid profile, protein level, and transaminase activity) induced by dexamethasone in rats. At doses of 120 and 60 mg/kg, Baillonella toxisperma also significantly decreases (p < 0.05; p < 0.01) postprandial hyperglycemia in insulin resistance rats. The results suggest that Baillonella toxisperma can manage insulin resistance and may be useful for the treatment of type 2 diabetes mellitus.

The Type 2 Diabetes Susceptibility PROX1 Gene Variants Are Associated with Postprandial Plasma Metabolites Profile in Non-Diabetic Men

The prospero homeobox 1 (PROX1) gene may show pleiotropic effects on metabolism. We evaluated postprandial metabolic alterations dependently on the rs340874 genotypes, and 28 non-diabetic men were divided into two groups: high-risk (HR)-genotype (CC-genotype carriers, n = 12, 35.3 ± 9.5 years old) and low-risk (LR)-genotype (allele T carriers, n = 16, 36.3 ± 7.0 years old). Subjects participated in two meal-challenge-tests with high-carbohydrate (HC, carbohydrates 89%) and normo-carbohydrate (NC, carbohydrates 45%) meal intake. Fasting and 30, 60, 120, and 180 min after meal intake plasma samples were fingerprinted by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). In HR-genotype men, the area under the curve (AUC) of acetylcarnitine levels was higher after the HC-meal [+92%, variable importance in the projection (VIP) = 2.88] and the NC-meal (+55%, VIP = 2.00) intake. After the NC-meal, the HR-risk genotype carriers presented lower AUCs of oxidized fatty acids (−81–66%, VIP = 1.43–3.16) and higher linoleic acid (+80%, VIP = 2.29), while after the HC-meal, they presented lower AUCs of ornithine (−45%, VIP = 1.83), sphingosine (−48%, VIP = 2.78), linoleamide (−45%, VIP = 1.51), and several lysophospholipids (−40–56%, VIP = 1.72–2.16). Moreover, lower AUC (−59%, VIP = 2.43) of taurocholate after the HC-meal and higher (+70%, VIP = 1.42) glycodeoxycholate levels after the NC-meal were observed. Our results revealed differences in postprandial metabolites from inflammatory and oxidative stress pathways, bile acids signaling, and lipid metabolism in PROX1 HR-genotype men. Further investigations of diet–genes interactions by which PROX1 may promote T2DM development are needed.

Abscisic acid stimulates the release of insulin and of GLP-1 in the rat perfused pancreas and intestine

AIMS

Previous results indicate that nanomolar concentrations of abscisic acid (ABA) stimulate insulin release from β-pancreatic cells in vitro and that oral ABA at 50 mg/kg increases plasma GLP-1 in the fasted rat. The aim of this study was to test the effect of ABA on the perfused rat pancreas and intestine, to verify the insulin- and incretin-releasing actions of ABA in controlled physiological models.

MATERIALS AND METHODS

Rat pancreas and small intestine were perfused with solutions containing ABA at high-micromolar concentrations, or control secretagogues. Insulin and GLP-1 concentrations in the venous effluent were analysed by radioimmunoassay, and ABA levels were determined by ELISA.

RESULTS

High micromolar concentrations of ABA induced GLP-1 secretion from the proximal half of the small intestine and insulin secretion from pancreas. GLP-1 stimulated ABA secretion from pancreas in a biphasic manner. Notably, a positive correlation was found between the ABA area under the curve (AUC) and the insulin AUC upon GLP-1 administration.

CONCLUSION

Our results indicate the existence of a cross talk between GLP-1 and ABA, whereby ABA stimulates GLP-1 secretion, and vice versa. Release of ABA could be considered as a new promising molecule in the strategy of type 2 diabetes treatment and as a new endogenous hormone in the regulation of glycaemia.

ω-6 Polyunsaturated Fatty Acids and Cardiometabolic Health: Current Evidence, Controversies, and Research Gaps

The 2015 Dietary Guidelines for Americans recommend limiting the intake of saturated fatty acids (SFAs) to <10% of energy/d and replacing dietary SFAs with unsaturated fatty acids. A Presidential Advisory from the American Heart Association recently released its evaluation of the relation between dietary fats and cardiovascular disease (CVD), and also recommended a shift from SFAs to unsaturated fatty acids, especially polyunsaturated fatty acids (PUFAs), in conjunction with a healthy dietary pattern. However, the suggestion to increase the intake of PUFAs in general, and omega-6 (n-6) PUFAs in particular, continues to be controversial. This review was undertaken to provide an overview of the evidence and controversies regarding the effects of ω-6 PUFAs on cardiometabolic health, with emphasis on risks and risk factors for CVD (coronary heart disease and stroke) and type 2 diabetes mellitus (T2D). Results from observational studies show that higher intake of ω-6 PUFAs, when compared with SFAs or carbohydrate, is associated with lower risks for CVD events (10-30%), CVD and total mortality (10-40%), and T2D (20-50%). Findings from intervention studies on cardiometabolic risk factors suggest that ω-6 PUFAs reduce concentrations of LDL cholesterol and non-HDL cholesterol in a dose-dependent manner compared with dietary carbohydrate, and have a neutral effect on blood pressure. Despite the concern that ω-6 fatty acids increase inflammation, current evidence from studies in humans does not support this view. In conclusion, these findings support current recommendations to emphasize consumption of ω-6 PUFAs as a replacement of SFAs; additional randomized controlled trials with cardiometabolic disease outcomes will help to more clearly define the benefits and risks of this policy.

Development of type 2 diabetes mellitus in people with intermediate hyperglycaemia

BACKGROUND

Intermediate hyperglycaemia (IH) is characterised by one or more measurements of elevated blood glucose concentrations, such as impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and elevated glycosylated haemoglobin A1c (HbA1c). These levels are higher than normal but below the diagnostic threshold for type 2 diabetes mellitus (T2DM). The reduced threshold of 5.6 mmol/L (100 mg/dL) fasting plasma glucose (FPG) for defining IFG, introduced by the American Diabetes Association (ADA) in 2003, substantially increased the prevalence of IFG. Likewise, the lowering of the HbA1c threshold from 6.0% to 5.7% by the ADA in 2010 could potentially have significant medical, public health and socioeconomic impacts.

OBJECTIVES

To assess the overall prognosis of people with IH for developing T2DM, regression from IH to normoglycaemia and the difference in T2DM incidence in people with IH versus people with normoglycaemia.

SEARCH METHODS

We searched MEDLINE, Embase, ClincialTrials.gov and the International Clinical Trials Registry Platform (ICTRP) Search Portal up to December 2016 and updated the MEDLINE search in February 2018. We used several complementary search methods in addition to a Boolean search based on analytical text mining.

SELECTION CRITERIA

We included prospective cohort studies investigating the development of T2DM in people with IH. We used standard definitions of IH as described by the ADA or World Health Organization (WHO). We excluded intervention trials and studies on cohorts with additional comorbidities at baseline, studies with missing data on the transition from IH to T2DM, and studies where T2DM incidence was evaluated by documents or self-report only.

DATA COLLECTION AND ANALYSIS

One review author extracted study characteristics, and a second author checked the extracted data. We used a tailored version of the Quality In Prognosis Studies (QUIPS) tool for assessing risk of bias. We pooled incidence and incidence rate ratios (IRR) using a random-effects model to account for between-study heterogeneity. To meta-analyse incidence data, we used a method for pooling proportions. For hazard ratios (HR) and odds ratios (OR) of IH versus normoglycaemia, reported with 95% confidence intervals (CI), we obtained standard errors from these CIs and performed random-effects meta-analyses using the generic inverse-variance method. We used multivariable HRs and the model with the greatest number of covariates. We evaluated the certainty of the evidence with an adapted version of the GRADE framework.

MAIN RESULTS

We included 103 prospective cohort studies. The studies mainly defined IH by IFG5.6 (FPG mmol/L 5.6 to 6.9 mmol/L or 100 mg/dL to 125 mg/dL), IFG6.1 (FPG 6.1 mmol/L to 6.9 mmol/L or 110 mg/dL to 125 mg/dL), IGT (plasma glucose 7.8 mmol/L to 11.1 mmol/L or 140 mg/dL to 199 mg/dL two hours after a 75 g glucose load on the oral glucose tolerance test, combined IFG and IGT (IFG/IGT), and elevated HbA1c (HbA1c5.7: HbA1c 5.7% to 6.4% or 39 mmol/mol to 46 mmol/mol; HbA1c6.0: HbA1c 6.0% to 6.4% or 42 mmol/mol to 46 mmol/mol). The follow-up period ranged from 1 to 24 years. Ninety-three studies evaluated the overall prognosis of people with IH measured by cumulative T2DM incidence, and 52 studies evaluated glycaemic status as a prognostic factor for T2DM by comparing a cohort with IH to a cohort with normoglycaemia. Participants were of Australian, European or North American origin in 41 studies; Latin American in 7; Asian or Middle Eastern in 50; and Islanders or American Indians in 5. Six studies included children and/or adolescents.Cumulative incidence of T2DM associated with IFG5.6, IFG6.1, IGT and the combination of IFG/IGT increased with length of follow-up. Cumulative incidence was highest with IFG/IGT, followed by IGT, IFG6.1 and IFG5.6. Limited data showed a higher T2DM incidence associated with HbA1c6.0 compared to HbA1c5.7. We rated the evidence for overall prognosis as of moderate certainty because of imprecision (wide CIs in most studies). In the 47 studies reporting restitution of normoglycaemia, regression ranged from 33% to 59% within one to five years follow-up, and from 17% to 42% for 6 to 11 years of follow-up (moderate-certainty evidence).Studies evaluating the prognostic effect of IH versus normoglycaemia reported different effect measures (HRs, IRRs and ORs). Overall, the effect measures all indicated an elevated risk of T2DM at 1 to 24 years of follow-up. Taking into account the long-term follow-up of cohort studies, estimation of HRs for time-dependent events like T2DM incidence appeared most reliable. The pooled HR and the number of studies and participants for different IH definitions as compared to normoglycaemia were: IFG5.6: HR 4.32 (95% CI 2.61 to 7.12), 8 studies, 9017 participants; IFG6.1: HR 5.47 (95% CI 3.50 to 8.54), 9 studies, 2818 participants; IGT: HR 3.61 (95% CI 2.31 to 5.64), 5 studies, 4010 participants; IFG and IGT: HR 6.90 (95% CI 4.15 to 11.45), 5 studies, 1038 participants; HbA1c5.7: HR 5.55 (95% CI 2.77 to 11.12), 4 studies, 5223 participants; HbA1c6.0: HR 10.10 (95% CI 3.59 to 28.43), 6 studies, 4532 participants. In subgroup analyses, there was no clear pattern of differences between geographic regions. We downgraded the evidence for the prognostic effect of IH versus normoglycaemia to low-certainty evidence due to study limitations because many studies did not adequately adjust for confounders. Imprecision and inconsistency required further downgrading due to wide 95% CIs and wide 95% prediction intervals (sometimes ranging from negative to positive prognostic factor to outcome associations), respectively.This evidence is up to date as of 26 February 2018.

AUTHORS' CONCLUSIONS

Overall prognosis of people with IH worsened over time. T2DM cumulative incidence generally increased over the course of follow-up but varied with IH definition. Regression from IH to normoglycaemia decreased over time but was observed even after 11 years of follow-up. The risk of developing T2DM when comparing IH with normoglycaemia at baseline varied by IH definition. Taking into consideration the uncertainty of the available evidence, as well as the fluctuating stages of normoglycaemia, IH and T2DM, which may transition from one stage to another in both directions even after years of follow-up, practitioners should be careful about the potential implications of any active intervention for people 'diagnosed' with IH.

Discordance in glycemic categories and regression to normality at baseline in 10,000 people in a Type 2 diabetes prevention trial

The world diabetes population quadrupled between 1980 and 2014 to 422 million and the enormous impact of Type 2 diabetes is recognised by the recent creation of national Type 2 diabetes prevention programmes. There is uncertainty about how to correctly risk stratify people for entry into prevention programmes, how combinations of multiple 'at high risk' glycemic categories predict outcome, and how the large recently defined 'at risk' population based on an elevated glycosylated haemoglobin (HbA1c) should be managed. We identified all 141,973 people at highest risk of diabetes in our population, and screened 10,000 of these with paired fasting plasma glucose and HbA1c for randomisation into a very large Type 2 diabetes prevention trial. Baseline discordance rate between highest risk categories was 45.6%, and 21.3-37.0% of highest risk glycaemic categories regressed to normality between paired baseline measurements (median 40 days apart). Accurate risk stratification using both fasting plasma glucose and HbA1c data, the use of paired baseline data, and awareness of diagnostic imprecision at diagnostic thresholds would avoid substantial overestimation of the true risk of Type 2 diabetes and the potential benefits (or otherwise) of intervention, in high risk subjects entering prevention trials and programmes.

Size and shape of the associations of glucose, HbA1c, insulin and HOMA-IR with incident type 2 diabetes: the Hoorn Study

AIMS/HYPOTHESIS

Glycaemic markers and fasting insulin are frequently measured outcomes of intervention studies. To extrapolate accurately the impact of interventions on the risk of diabetes incidence, we investigated the size and shape of the associations of fasting plasma glucose (FPG), 2 h post-load glucose (2hPG), HbA_1c, fasting insulin and HOMA-IR with incident type 2 diabetes mellitus.

METHODS

The study population included 1349 participants aged 50-75 years without diabetes at baseline (1989) from a population-based cohort in Hoorn, the Netherlands. Incident type 2 diabetes was defined by the WHO 2011 criteria or known diabetes at follow-up. Logistic regression models were used to determine the associations of the glycaemic markers, fasting insulin and HOMA-IR with incident type 2 diabetes. Restricted cubic spline logistic regressions were conducted to investigate the shape of the associations.

RESULTS

After a mean follow-up duration of 6.4 (SD 0.5) years, 152 participants developed diabetes (11.3%); the majority were screen detected by high FPG. In multivariate adjusted models, ORs (95% CI) for incident type 2 diabetes for the highest quintile in comparison with the lowest quintile were 9.0 (4.4, 18.5) for FPG, 6.1 (2.9, 12.7) for 2hPG, 3.8 (2.0, 7.2) for HbA_1c, 1.9 (0.9, 3.6) for fasting insulin and 2.8 (1.4, 5.6) for HOMA-IR. The associations of FPG and HbA_1c with incident diabetes were non-linear, rising more steeply at higher values.

CONCLUSIONS/INTERPRETATION

FPG was most strongly associated with incident diabetes, followed by 2hPG, HbA_1c, HOMA-IR and fasting insulin. The strong association with FPG is probably because FPG is the most frequent marker for diabetes diagnosis. Non-linearity of associations between glycaemic markers and incident type 2 diabetes should be taken into account when estimating future risk of type 2 diabetes based on glycaemic markers.

Derivation and external validation of a clinical version of the German Diabetes Risk Score (GDRS) including measures of HbA1c

OBJECTIVE

The German Diabetes Risk Score (GDRS) is a diabetes prediction model which only includes non-invasively measured risk factors. The aim of this study was to extend the original GDRS by hemoglobin A1c (HbA1c) and validate this clinical GDRS in the nationwide German National Health Interview and Examination Survey 1998 (GNHIES98) cohort.

RESEARCH DESIGN AND METHODS

Extension of the GDRS was based on the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study with baseline assessment conducted between 1994 and 1998 (N=27 548, main age range 35-65 years). Cox regression was applied with the original GDRS and HbA1c as independent variables. The extended model was evaluated by discrimination (C-index (95% CI)), calibration (calibration plots and expected to observed (E:O) ratios (95% CI)), and reclassification (net reclassification improvement, NRI (95% CI)). For validation, data from the GNHIES98 cohort with baseline assessment conducted between 1997 and 1999 were used (N=3717, age range 18-79 years). Missing data were handled with multiple imputation.

RESULTS

After 5 years of follow-up 593 incident cases of type 2 diabetes occurred in EPIC-Potsdam and 86 in the GNHIES98 cohort. In EPIC-Potsdam, the C-index for the clinical GDRS was 0.87 (0.81 to 0.92) and the overall NRI was 0.26 (0.21 to 0.30), with a stronger improvement among cases compared with non-cases (NRI_cases: 0.24 (0.19 to 0.28); NRI_non-cases: 0.02 (0.01 to 0.02)). Almost perfect calibration was observed with a slight tendency toward overestimation, which was also reflected by an E:O ratio of 1.07 (0.99 to 1.16). In the GNHIES98 cohort, discrimination was excellent with a C-index of 0.91 (0.88 to 0.94). After recalibration, the calibration plot showed underestimation of diabetes risk in the highest risk group, while the E:O ratio indicated overall perfect calibration (1.02 (0.83 to 1.26)).

CONCLUSIONS

The clinical GDRS provides the opportunity to apply the original GDRS as a first step in risk assessment, which can then be extended in clinical practice with HbA1c whenever it was measured.

Cooking Classes: A Diabetes Self-Management Support Intervention Enhancing Clinical Values

Purpose

The purpose of this study is to examine the relationship between Healthy Teaching Kitchen (HTK) attendance among veterans who are diagnosed with type 2 diabetes mellitus (T2DM) and clinical outcomes as measured by A1C and blood pressure.

Methods

This retrospective chart review collected data from veterans with T2DM who participated in the Diabetes Self-Management Support (DSMS) HTK program at the Louis Stokes Cleveland VA Medical Center (LSCVAMC) between February 2013 and May 2016. Data collected included demographic information, frequency of DSMS HTK attendance, 3 A1C values, and 3 blood pressure values. Each subject was assigned to 1 of 4 quartiles based on frequency of DSMS HTK attendance.

Results

A1C values of all groups improved over time, regardless of DSMS HTK attendance quartile. However, as total DSMS HTK class attendance increased, there was a significant decrease in the A1C difference score.

Conclusions

Participation in a DSMS program that focuses on healthy, economical cooking skills may lead to a significant improvement in A1C regardless of frequency of attendance. However, individuals with more frequent attendance may experience additional improvement in glycemic control.

Diabetes screening intervals based on risk stratification

BACKGROUND

Guidelines for frequency of Type 2 diabetes mellitus (DM) screening remain unclear, with proposed screening intervals typically based on expert opinion. This study aims to demonstrate that HbA1c screening intervals may differ substantially when considering individual risk for diabetes.

METHODS

This was a multi-institutional retrospective open cohort study. Data were collected between April 1999 to March 2014 from one urban and one rural cohort in Japan. After categorization by age, we stratified individuals based on cardiovascular disease risk (Framingham 10-year cardiovascular risk score) and body mass index (BMI). We adapted a signal-to-noise method for distinguishing true HbA1c change from measurement error by constructing a linear random effect model to calculate signal and noise of HbA1c. Screening interval for HbA1c was defined as informative when the signal-to-noise ratio exceeded 1.

RESULTS

Among 96,456 healthy adults, 46,284 (48.0%) were male; age (range) and mean HbA1c (SD) were 48 (30-74) years old and 5.4 (0.4)%, respectively. As risk increased among those 30-44 years old, HbA1c screening intervals for detecting Type 2 DM consistently decreased: from 10.5 (BMI <18.5) to 2.4 (BMI > 30) years, and from 8.0 (Framingham Risk Score <10%) to 2.0 (Framingham Risk Score ≥20%) years. This trend was consistent in other age and risk groups as well; among obese 30-44 year olds, we found substantially shorter intervals compared to other groups.

CONCLUSION

HbA1c screening intervals for identification of DM vary substantially by risk factors. Risk stratification should be applied when deciding an optimal HbA1c screening interval in the general population to minimize overdiagnosis and overtreatment.

Reactive oxygen species: sources, consequences and targeted therapy in type 2 diabetes

Oxidative stress has been considered as a central mediator in the progression of diabetic complication. The intracellular reactive oxygen species (ROS) leads to oxidative stress and it is raised from the mitochondria as well as by activation of five major pathways: increased polyol pathway flux, activation of protein kinase C (PKC) pathway, increased formation of advanced glycation end products (AGEs), over activity of hexosamine pathway and increased production of angiotensin II. The increased ROS through these pathways leads to β-cell dysfunction and insulin resistance, responsible for cell damage and death. This review not only highlights the sources of ROS production and their involvement in the progression of diabetes, but also emphasizes on pharmacological interventions and targeting of ROS in type 2 diabetes. This review summarizes the ROS as potential therapeutic targets, based on a putative mechanism in the progression of the diabetes. It also summarizes current knowledge of ROS activation in type 2 diabetes as well as ROS as a possible target for its treatment. Eventually, it would be a promising target for various strategies and drugs to modulate ROS levels in diabetes.

Effects of Saturated Fat, Polyunsaturated Fat, Monounsaturated Fat, and Carbohydrate on Glucose-Insulin Homeostasis: A Systematic Review and Meta-analysis of Randomised Controlled Feeding Trials

BACKGROUND

Effects of major dietary macronutrients on glucose-insulin homeostasis remain controversial and may vary by the clinical measures examined. We aimed to assess how saturated fat (SFA), monounsaturated fat (MUFA), polyunsaturated fat (PUFA), and carbohydrate affect key metrics of glucose-insulin homeostasis.

METHODS AND FINDINGS

We systematically searched multiple databases (PubMed, EMBASE, OVID, BIOSIS, Web-of-Knowledge, CAB, CINAHL, Cochrane Library, SIGLE, Faculty1000) for randomised controlled feeding trials published by 26 Nov 2015 that tested effects of macronutrient intake on blood glucose, insulin, HbA1c, insulin sensitivity, and insulin secretion in adults aged ≥18 years. We excluded trials with non-isocaloric comparisons and trials providing dietary advice or supplements rather than meals. Studies were reviewed and data extracted independently in duplicate. Among 6,124 abstracts, 102 trials, including 239 diet arms and 4,220 adults, met eligibility requirements. Using multiple-treatment meta-regression, we estimated dose-response effects of isocaloric replacements between SFA, MUFA, PUFA, and carbohydrate, adjusted for protein, trans fat, and dietary fibre. Replacing 5% energy from carbohydrate with SFA had no significant effect on fasting glucose (+0.02 mmol/L, 95% CI = -0.01, +0.04; n trials = 99), but lowered fasting insulin (-1.1 pmol/L; -1.7, -0.5; n = 90). Replacing carbohydrate with MUFA lowered HbA1c (-0.09%; -0.12, -0.05; n = 23), 2 h post-challenge insulin (-20.3 pmol/L; -32.2, -8.4; n = 11), and homeostasis model assessment for insulin resistance (HOMA-IR) (-2.4%; -4.6, -0.3; n = 30). Replacing carbohydrate with PUFA significantly lowered HbA1c (-0.11%; -0.17, -0.05) and fasting insulin (-1.6 pmol/L; -2.8, -0.4). Replacing SFA with PUFA significantly lowered glucose, HbA1c, C-peptide, and HOMA. Based on gold-standard acute insulin response in ten trials, PUFA significantly improved insulin secretion capacity (+0.5 pmol/L/min; 0.2, 0.8) whether replacing carbohydrate, SFA, or even MUFA. No significant effects of any macronutrient replacements were observed for 2 h post-challenge glucose or insulin sensitivity (minimal-model index). Limitations included a small number of trials for some outcomes and potential issues of blinding, compliance, generalisability, heterogeneity due to unmeasured factors, and publication bias.

CONCLUSIONS

This meta-analysis of randomised controlled feeding trials provides evidence that dietary macronutrients have diverse effects on glucose-insulin homeostasis. In comparison to carbohydrate, SFA, or MUFA, most consistent favourable effects were seen with PUFA, which was linked to improved glycaemia, insulin resistance, and insulin secretion capacity.

Examining the relationship between HbA1c and diabetes risk models in a European population indicates a lower threshold to identify 'high risk' is required

This study examined whether changes in HbA1c values are reflected in the risk scores and categories of four validated risk-assessment tools (QDiabetes, Leicester Risk Assessment, Finnish Diabetes Risk Score and Cambridge Risk Score). Retrospective analysis was performed on 651 individuals with no prior diagnosis of cardiovascular disease or diabetes who participated in a UK workplace-based risk-assessment initiative. There were significant positive correlations (p < 0.01) revealed between HbA1c values and predicted risk scores: QDiabetes (r = 0.362), Leicester Risk Assessment (r = 0.315), Finnish Diabetes Risk Score (r = 0.202) and Cambridge Risk Score (r = 0.335). HbA1c values increased within risk prediction categories, and at 'high-risk' categories, median HbA1c values were at least 39 mmol mol(-1) (5.7%) irrespective of gender or risk-assessment model. Overall, an association is present between increases in HbA1c scores and predicted risk of type 2 diabetes. Furthermore, the 'high-risk' median HbA1c values in each of the risk assessments are more akin to the lower American recommendations rather than those suggested by the UK expert group.

Repeat Cardiovascular Risk Assessment after Four Years: Is There Improvement in Risk Prediction?

BACKGROUND

Framingham risk equations are widely used to predict cardiovascular disease based on health information from a single time point. Little is known regarding use of information from repeat risk assessments and temporal change in estimated cardiovascular risk for prediction of future cardiovascular events. This study was aimed to compare the discrimination and risk reclassification of approaches using estimated cardiovascular risk at single and repeat risk assessments.

METHODS

Using data on 12,197 individuals enrolled in EPIC-Norfolk cohort, with 12 years of follow-up, we examined rates of cardiovascular events by levels of estimated absolute risk (Framingham risk score) at the first and second health examination four years later. We calculated the area under the receiver operating characteristic curve (aROC) and risk reclassification, comparing approaches using information from single and repeat risk assessments (i.e., estimated risk at different time points).

RESULTS

The mean Framingham risk score increased from 15.5% to 17.5% over a mean of 3.7 years from the first to second health examination. Individuals with high estimated risk (≥20%) at both health examinations had considerably higher rates of cardiovascular events than those who remained in the lowest risk category (<10%) in both health examinations (34.0 [95%CI 31.7-36.6] and 2.7 [2.2-3.3] per 1,000 person-years respectively). Using information from the most up-to-date risk assessment resulted in a small non-significant change in risk classification over the previous risk assessment (net reclassification improvement of -4.8%, p>0.05). Using information from both risk assessments slightly improved discrimination compared to information from a single risk assessment (aROC 0.76 and 0.75 respectively, p<0.001).

CONCLUSIONS

Using information from repeat risk assessments over a period of four years modestly improved prediction, compared to using data from a single risk assessment. However, this approach did not improve risk classification.

Performance of HbA1c for the prediction of diabetes in a rural community in Korea

AIM

To investigate the performance of HbA1c in predicting incident diabetes among Korean adults with normal fasting glucose and impaired fasting glucose levels.

METHODS

This study used data from the Korean Genome Epidemiology Study-Kangwha Study. A prospective analysis was carried out on 2079 people (820 men and 1259 women) who completed follow-up examinations up until 2013. Diabetes was defined as fasting blood glucose level ≥ 7.0 mmol/l, HbA1c level ≥ 48 mmol/mol (6.5%), or current treatment for diabetes. Areas under the receiver-operating characteristic curves were used to assess the different performances of HbA1c , glucose and insulin in predicting diabetes.

RESULTS

The median follow-up time was 3.97 years, during which 7.7% of men and 6.3% of women developed incident diabetes. The areas under the receiver-operating curves (95% CI) for diabetes prediction were 0.740 (0.692-0.787) for HbA1c , 0.716 (0.667-0.764) for glucose and 0.598 (0.549-0.648) for insulin. HbA1c showed better predictive power in people with impaired fasting glucose (area under the curve 0.753, 95% CI 0.685-0.821) than in those with normal glucose (area under the curve 0.648, 95% CI 0.577-0.719). An HbA1c threshold of 40 mmol/mol (5.8%) was found to have the highest predictive value for diabetes, with a relative risk of 6.30 (95% CI 3.49-11.35) in men and 3.52 (95% CI 2.06-6.03) in women after adjusting for age, waist circumference, triglycerides, hypertension, family history of diabetes, smoking, alcohol intake, exercise and baseline glucose level.

CONCLUSIONS

HbA1c can be used to identify people at high risk for the development of diabetes, especially in those with impaired fasting glucose levels.

Glycated hemoglobin and incident type 2 diabetes in singaporean chinese adults: the Singapore Chinese health study

Background

The American Diabetes Association recently included glycated hemoglobin in the diagnostic criteria for diabetes, but research on the utility of this biomarker in Southeast Asians is scant. The aim of this study was to evaluate the association between percent HbA1c and incident diabetes in an Asian population of adult men and women without reported diabetes.

Methods

Data analysis of 5,770 men and women enrolled in the Singapore Chinese Health Study who provided a blood sample at the follow-up I visit (1999–2004) and had no cancer and no reported history of diabetes or cardiovascular disease events. Diabetes was defined as self-report of physician diagnosis, identified at the follow-up II visit (2006–2010).

Results

Hazard ratios (and 95% confidence intervals) for incident diabetes by 5 categories of HbA1c were estimated with Cox regression models and continuous HbA1c with cubic spline analysis. Compared to individuals with an HbA1c ≤ 5.7% (≤39 mmol/mol), individuals with HbA1c 5.8–5.9% (40–41 mmol/mol), 6.0–6.1% (42–43 mmol/mol), 6.2–6.4% (44–47 mmol/mol), and ≥ 6.5% (≥48 mmol/mol) had significantly increased risk for incident diabetes during follow-up. In cubic spline analysis, levels below 5.7% HbA1c were not significantly associated with incident diabetes.

Conclusions

Our study found a strong and graded association with HbA1c 5.8% and above with incident diabetes in Chinese men and women.

Building a population-based diabetes register: an Italian experience

AIMS

To describe the methodology used to set up the Reggio Emilia (northern Italy) Diabetes Register. The prevalence estimates on December 31st, 2009 are also provided.

METHODS

The Diabetes Register covers all residents in the Reggio Emilia province. The register was created by deterministic linkage of six routinely collected data sources through a definite algorithm able to ascertain cases and to distinguish type of diabetes and model of care: Hospital Discharge, Drug Dispensation, Biochemistry Laboratory, Disease-specific Exemption, Diabetes Outpatient Clinics, and Mortality databases. Using these data, we estimated crude prevalence on December 31st, 2009 by sex, age groups, and type of diabetes.

RESULTS

There were 25,425 ascertained prevalent cases on December 31st, 2009. Drug Dispensation and Exemption databases made the greatest contribution to prevalence. Analyzing overlapping sources, more than 80% of cases were reported by at least two sources. Crude prevalence was 4.8% and 5.9% for the whole population and for people aged 18 years and over, respectively. Males accounted for 53.6%. Type 1 diabetes accounted for 3.8% of cases, while people with Type 2 diabetes were the overriding majority (91.2%), and Diabetes Outpatient Clinics treated 75.4% of people with Type 2 diabetes.

CONCLUSION

The Register is able to quantify the burden of disease, the first step in planning, implementing, and monitoring appropriate interventions. All data sources contributed to completeness and/or accuracy of the Register. Although all cases are identified by deterministic record linkage, manual revision and General Practitioner involvement are still necessary when information is insufficient or conflicting.

Change in HbA1c over 3 years does not improve the prediction of cardiovascular disease over and above HbA1c measured at a single time point

AIMS/HYPOTHESIS

HbA1c is an important risk factor for cardiovascular disease (CVD), with 1% higher HbA1c levels associated with a 10-20% increased risk of CVD. Little is known about the association between change in HbA1c over time and cardiovascular risk in non-diabetic populations. This study examined the association between change in HbA1c over time and cardiovascular risk in a non-diabetic British population.

METHODS

We used data on HbA1c collected at baseline and at a second health examination 3 years later among a population of 5,790 non-diabetic men and women who participated in the European Prospective Investigation of Cancer (EPIC)-Norfolk. The association between change in HbA1c over 3 years and incident cardiovascular events over the following 8 years was examined using multivariate Cox regression. We also examined whether information on change in HbA1c over time improved prediction of cardiovascular events over a single measure of HbA1c by comparing the area under the receiver operating characteristic curves (aROC) and computing the net reclassification improvement.

RESULTS

The mean change (SD) in HbA1c over 3 years was 0.13% (0.52). During 44,596 person-years of follow-up, 529 cardiovascular events occurred (incidence 11.9 per 1,000 person-years). Each 0.5% rise in HbA1c over 3 years was associated with a 9% increase in risk of a cardiovascular event (HR 1.09; 95% CI 1.01, 1.18) after adjustment for baseline HbA1c and other major cardiovascular risk factors. However, change in HbA1c was not associated with cardiovascular risk after adjustment for HbA1c at follow-up. Multivariate models with and without information on change in HbA1c over time showed a similar aROC of 0.78. Adding change in HbA1c to the model with HbA1c at follow-up did not improve risk classification.

CONCLUSIONS/INTERPRETATION

Addition of information on change in HbA1c over 3 years did not improve the prediction of CVD over and above information on HbA1c and other major cardiovascular risk factors from a single time point.

Genetic and molecular insights into the role of PROX1 in glucose metabolism

Genome-wide association studies have shown that the rs340874 single nucleotide polymorphism (SNP) in PROX1 is a genetic susceptibility factor for type 2 diabetes. We conducted genetic and molecular studies to better understand the role of PROX1 in type 2 diabetes. We assessed the impact of the whole common genetic variability of PROX1 (80 SNPs) on type 2 diabetes-related biochemical traits in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study (n = 1,155). Three SNPs (rs340838, rs340837, and rs340836) were significantly associated with fasting plasma insulin levels (P ≤ 0.00295). We evaluated the impact of nine PROX1 SNPs (the three insulin-associated SNPs plus six SNPs in strong linkage disequilibrium) on luciferase reporter gene expression. The insulin-lowering alleles of rs340874, rs340873, and rs340835 were associated with lower luciferase activity in MIN6 and HepG2 cells (except for rs340874, which was in HepG2 cells only). Electrophoretic mobility shift assays indicated that specific nuclear protein bindings occur at the three SNPs in HepG2 cells, with allele-binding differences for rs340874. We also showed that the knockdown of Prox1 expression by small interfering RNAs in INS-1E cells resulted in a 1.7-fold reduction in glucose-stimulated insulin secretion. All together, we propose that reduced expression of PROX1 by cis-regulatory variants results in altered β-cell insulin secretion and thereby confers susceptibility to type 2 diabetes.

Type 2 diabetes mellitus: a review of current trends

Type 2 diabetes mellitus (DM) is a chronic metabolic disorder in which prevalence has been increasing steadily all over the world. As a result of this trend, it is fast becoming an epidemic in some countries of the world with the number of people affected expected to double in the next decade due to increase in ageing population, thereby adding to the already existing burden for healthcare providers, especially in poorly developed countries. This review is based on a search of Medline, the Cochrane Database of Systemic Reviews, and citation lists of relevant publications. Subject heading and key words used include type 2 diabetes mellitus, prevalence, current diagnosis, and current treatment. Only articles in English were included. Screening and diagnosis is still based on World Health Organization (WHO) and American Diabetes Association (ADA) criteria which include both clinical and laboratory parameters. No cure has yet been found for the disease; however, treatment modalities include lifestyle modifications, treatment of obesity, oral hypoglycemic agents, and insulin sensitizers like metformin, a biguanide that reduces insulin resistance, is still the recommended first line medication especially for obese patients. Other effective medications include non-sulfonylurea secretagogues, thiazolidinediones, alpha glucosidase inhibitors, and insulin. Recent research into the pathophysiology of type 2 DM has led to the introduction of new medications like glucagon-like peptide 1 analogoues: dipeptidyl peptidase-IV inhibitors, inhibitors of the sodium-glucose cotransporter 2 and 11ß-hydroxysteroid dehydrogenase 1, insulin-releasing glucokinase activators and pancreatic-G-protein-coupled fatty-acid-receptor agonists, glucagon-receptor antagonists, metabolic inhibitors of hepatic glucose output and quick-release bromocriptine. Inhaled insulin was licensed for use in 2006 but has been withdrawn from the market because of low patronage.

Estimating the potential population impact of stepwise screening strategies for identifying and treating individuals at high risk of Type 2 diabetes: a modelling study

BACKGROUND

Diabetes risk assessment has been proposed as part of the National Health Service Health Checks programme, and HbA(1c) has recently been recommended as a diagnostic test for diabetes at a threshold of 48 mmol/mol (6.5%). We estimated the potential population impact of different stepwise screening strategies to identify individuals at high risk who might be offered preventive interventions.

METHODS

Using data from 5910 participants in the European Prospective Investigation of Cancer (EPIC)-Norfolk cohort with HbA(1c) measurements, we modelled different stepwise screening strategies for identifying and treating individuals at high risk of Type 2 diabetes using different HbA(1c) cut-off points with and without a stage of prestratification. For each strategy, we estimated the number needed to have a diagnostic test, the number needed to treat to prevent one new case of Type 2 diabetes, and the number of new cases that could be prevented in the population over 3 years. Relative risk reductions for estimated effects of intensive lifestyle intervention were derived from the US Diabetes Prevention Program.

RESULTS

Compared with inviting all individuals in an average primary care trust for a diagnostic test, a stepwise screening approach using simple routine data such as age and anthropometric indices could prevent a slightly lower number (lower-upper estimates) of new cases of Type 2 diabetes over 3 years (224 [130-359] and 193 [109-315] cases respectively) but would only require half the population to be invited for a diagnostic blood test. A total of 162 (88-274) cases could be prevented by inviting individuals with a Cambridge risk score of ≥ 0.15, with only 40% of the total population requiring diagnostic blood tests. Using a participant completed questionnaire for risk assessment (FINDRISC) was less effective, mainly relating to the questionnaire response rate. Providing preventive interventions to those with a lower HbA(1c) of 37-< 48 mmol/mol (5.5-< 6.5%) could prevent more cases but with a disproportionately higher workload, compared with using the recommended HbA(1c) threshold of 42-< 48 mmol/mol (6.0-< 6.5%).

CONCLUSIONS

Compared with mass screening, an approach using routine data for risk stratification followed by an HbA(1c) test with a threshold of 42-< 48 mmol/mol (6.0-< 6.5%) for identifying individuals suitable for preventive interventions might prevent slightly fewer cases of Type 2 diabetes but with potential cost-savings.

HbA1c 5·7-6·4% and impaired fasting plasma glucose for diagnosis of prediabetes and risk of progression to diabetes in Japan (TOPICS 3): a longitudinal cohort study

BACKGROUND

The clinical relevance of the diagnostic criteria for prediabetes to prediction of progression to diabetes has been little studied. We aimed to compare the prevalence of prediabetes when assessed by the new glycated haemoglobin A(1c) (HbA(1c)) 5·7-6·4% criterion or by impaired fasting glucose, and assessed differences in progression rate to diabetes between these two criteria for prediabetes in a Japanese population.

METHODS

Our longitudinal cohort study included 4670 men and 1571 women aged 24-82 years without diabetes at baseline (diabetes was defined as fasting plasma glucose ≥7·0 mmol/L, self-reported clinician-diagnosed diabetes, or HbA(1c) ≥6·5%) who attended Toranomon Hospital (Tokyo, Japan) for a routine health check between 1997 and 2003. Participants with a baseline diagnosis of prediabetes according to impaired fasting glucose (fasting plasma glucose 5·6-6·9 mmol/L) or HbA(1c) 5·7-6·4%, or both, were divided into four groups on the basis of baseline diagnosis of prediabetes. Rate of progression to diabetes was assessed annually.

FINDINGS

Mean follow-up was 4·7 (SD 0·7) years. 412 (7%) of 6241 participants were diagnosed with prediabetes on the basis of the HbA(1c) 5·7-6·4% criterion. Screening by HbA(1c) alone missed 1270 (61%) of the 2092 prediabetic individuals diagnosed by a combination of impaired fasting glucose and HbA(1c) 5·7-6·4%. Overall cumulative probability of progression to diabetes did not differ significantly between participants with prediabetes discordantly diagnosed by either HbA(1c) or impaired fasting glucose alone (incidence was 7% for HbA(1c) alone [n=412 individuals and 30 incident cases] and 9% for impaired fasting glucose alone [n=1270, 108 cases]; log-rank test, p=0·3317). Multivariate-adjusted hazard ratios for incident diabetes were 6·16 (95% CI 4·33-8·77) for those diagnosed with prediabetes by impaired fasting glucose alone and 6·00 (3·76-9·56) for diagnosis by HbA(1c) alone, and were substantially increased to 31·9 (22·6-45·0) for diagnosis by both impaired fasting glucose and HbA(1c) compared with normoglycaemic individuals.

INTERPRETATION

Diagnosis of prediabetes by both the new HbA(1c) criterion and impaired fasting glucose identified individuals with an increased risk of progression to diabetes. Although the new HbA(1c) criterion identified fewer individuals at high risk than did impaired fasting glucose, the predictive value for progression to diabetes assessed by HbA(1c) 5·7-6·4% was similar to that assessed by impaired fasting glucose alone. The two tests used together could efficiently target people who are most likely to develop diabetes and allow for early intervention.

FUNDING

Japan Society for the Promotion of Science; Ministry of Health Labor and Welfare, Japan.