A meta-analysis of diabetes risk prediction models applied to prediabetes screening

AIM

To provide a systematic overview of diabetes risk prediction models used for prediabetes screening to promote primary prevention of diabetes.

METHODS

The Cochrane, PubMed, Embase, Web of Science and China National Knowledge Infrastructure (CNKI) databases were searched for a comprehensive search period of 30 August 30, 2023, and studies involving diabetes prediction models for screening prediabetes risk were included in the search. The Quality Assessment Checklist for Diagnostic Studies (QUADAS-2) tool was used for risk of bias assessment and Stata and R software were used to pool model effect sizes.

RESULTS

A total of 29 375 articles were screened, and finally 20 models from 24 studies were included in the systematic review. The most common predictors were age, body mass index, family history of diabetes, history of hypertension, and physical activity. Regarding the indicators of model prediction performance, discrimination and calibration were only reported in 79.2% and 4.2% of studies, respectively, resulting in significant heterogeneity in model prediction results, which may be related to differences between model predictor combinations and lack of important methodological information.

CONCLUSIONS

Numerous models are used to predict diabetes, and as there is an association between prediabetes and diabetes, researchers have also used such models for screening the prediabetic population. Although it is a new clinical practice to explore, differences in glycaemic metabolic profiles, potential complications, and methods of intervention between the two populations cannot be ignored, and such differences have led to poor validity and accuracy of the models. Therefore, there is no recommended optimal model, and it is not recommended to use existing models for risk identification in alternative populations; future studies should focus on improving the clinical relevance and predictive performance of existing models.

Does metformin reduce the risk of cancer in obesity and diabetes? A systematic review and meta-analysis

AIM

To evaluate the effect of metformin on cancer incidence in subjects with overweight/obesity and/or prediabetes/diabetes.

MATERIALS AND METHODS

We searched MEDLINE, Embase and CENTRAL for randomized controlled trials (RCTs) in adults with overweight/obesity and/or prediabetes/diabetes that compared metformin to other interventions for ≥24 weeks. Independent reviewers selected and extracted data including population and intervention characteristics and new diagnoses of cancer. We used the RoB 2.0 risk-of-bias tool and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework to assess risk of bias and certainty of evidence.

RESULTS

From 14 895 records after removal of duplicates, 27 trials were included, providing a total of 10 717 subjects in the metformin group and 10 003 in the control group, with 170 and 208 new cases of cancer, respectively. Using a random-effects model, the relative risk was 1.07 (95% confidence interval 0.87-1.31), with similar results in subgroup analyses by study duration or effect of control intervention on weight. Risk of bias in most studies was low, and no evidence of publication bias was found. Trial sequential analysis provided evidence that the cumulative sample size was large enough to exclude a significant effect of metformin on cancer incidence.

CONCLUSIONS

Metformin did not reduce cancer incidence in RCTs involving subjects with overweight/obesity and/or prediabetes/diabetes.

Active vitamin D treatment in the prevention of sarcopenia in adults with prediabetes (DPVD ancillary study): a randomised controlled trial

BACKGROUND

Observational studies show inverse associations between serum 25-hydroxyvitamin D concentrations and sarcopenia incidence; however, it remains unclear whether treatment with vitamin D prevents its development. We aimed to assess whether treatment with active vitamin D (eldecalcitol [0·75 μg per day]) can reduce the development of sarcopenia among adults with prediabetes.

METHODS

This randomised, double-blind, placebo-controlled, multicenter trial as an ancillary study was conducted at 32 clinics and hospital sites in Japan. Participants were assigned (1:1) by using a central randomisation method in which a randomisation list was made for each hospital separately using a stratified permuted block procedure. The primary endpoint was sarcopenia incidence during 3 years in the intention-to-treat population defined as weak handgrip strength (<28 kg for men and <18 kg for women) and low appendicular skeletal muscle index (<7·0 kg/m2 for men and <5·7 kg/m2 for women in bioelectrical impedance analysis). Although the usual criterion of hypercalcaemia was 10·4 mg/dL (2·6 mmol/L) or higher, hypercalcaemia that was enough to discontinue the study was defined as 11·0 mg/dL or higher. This study is registered with the UMIN clinical trials registry, UMIN000005394.

FINDINGS

A total of 1094 participants (548 in the eldecalcitol group and 546 in the placebo group; 44·2% [484 of 1094] women; mean age 60·8 [SD 9·2] years) were followed up for a median of 2·9 (IQR 2·8-3·0) years. Eldecalcitol treatment as compared with placebo showed statistically significant preventive effect on sarcopenia incidence (25 [4·6%] of 548 participants in the eldecalcitol group and 48 [8·8%] of 546 participants in the placebo group; hazard ratio 0·51; 95% CI 0·31 to 0·83; p=0·0065). The incidence of adverse events did not differ between the two groups.

INTERPRETATION

We found that treatment with eldecalcitol has the potential to prevent the onset of sarcopenia among people with prediabetes via increasing skeletal muscle volume and strength, which might lead to a substantial risk reduction of falls.

FUNDING

Kitakyushu Medical Association.

TRANSLATION

For the Japanese translation of the abstract see Supplementary Materials section.

Effect of Testosterone on Progression From Prediabetes to Diabetes in Men With Hypogonadism: A Substudy of the TRAVERSE Randomized Clinical Trial

Importance

The effect of testosterone replacement therapy (TRT) in men with hypogonadism on the risk of progression from prediabetes to diabetes or of inducing glycemic remission in those with diabetes is unknown.

Objective

To evaluate the efficacy of TRT in preventing progression from prediabetes to diabetes in men with hypogonadism who had prediabetes and in inducing glycemic remission in those with diabetes.

Design, Setting, and Participants

This nested substudy, an intention-to-treat analysis, within a placebo-controlled randomized clinical trial (Testosterone Replacement Therapy for Assessment of Long-Term Vascular Events and Efficacy Response in Hypogonadal Men [TRAVERSE]) was conducted at 316 trial sites in the US. Participants included men aged 45 to 80 years with hypogonadism and prediabetes or diabetes who were enrolled in TRAVERSE between May 23, 2018, and February 1, 2022.

Intervention

Participants were randomized 1:1 to receive 1.62% testosterone gel or placebo gel until study completion.

Main Outcomes and Measures

The primary end point was the risk of progression from prediabetes to diabetes, analyzed using repeated-measures log-binomial regression. The secondary end point was the risk of glycemic remission (hemoglobin A1c level <6.5% [to convert to proportion of total hemoglobin, multiply by 0.01] or 2 fasting glucose measurements <126 mg/dL [to convert to mmol/L, multiply by 0.0555] without diabetes medication) in men who had diabetes.

Results

Of 5204 randomized participants, 1175 with prediabetes (mean [SD] age, 63.8 [8.1] years) and 3880 with diabetes (mean [SD] age, 63.2 [7.8] years) were included in this study. Mean (SD) hemoglobin A1c level in men with prediabetes was 5.8% (0.4%). Risk of progression to diabetes did not differ significantly between testosterone and placebo groups: 4 of 598 (0.7%) vs 8 of 562 (1.4%) at 6 months, 45 of 575 (7.8%) vs 57 of 533 (10.7%) at 12 months, 50 of 494 (10.1%) vs 67 of 460 (14.6%) at 24 months, 46 of 359 (12.8%) vs 52 of 330 (15.8%) at 36 months, and 22 of 164 (13.4%) vs 19 of 121 (15.7%) at 48 months (omnibus test P = .49). The proportions of participants with diabetes who experienced glycemic remission and the changes in glucose and hemoglobin A1c levels were similar in testosterone- and placebo-treated men with prediabetes or diabetes.

Conclusions and Relevance

In men with hypogonadism and prediabetes, the incidence of progression from prediabetes to diabetes did not differ significantly between testosterone- and placebo-treated men. Testosterone replacement therapy did not improve glycemic control in men with hypogonadism and prediabetes or diabetes. These findings suggest that TRT alone should not be used as a therapeutic intervention to prevent or treat diabetes in men with hypogonadism.

Trial Registration

ClinicalTrials.gov Identifier: NCT03518034.

Nascent shifts in renal cellular metabolism, structure, and function due to chronic empagliflozin in prediabetic mice

Sodium-glucose cotransporter, type 2 inhibitors (SGLT2i) are emerging as the gold standard for treatment of type 2 diabetes (T2D) with renal protective benefits independent of glucose lowering. We took a high-level approach to evaluate the effects of the SGLT2i, empagliflozin (EMPA) on renal metabolism and function in a prediabetic model of metabolic syndrome. Male and female 12-wk-old TallyHo (TH) mice, and their closest genetic lean strain (Swiss-Webster, SW) were treated with a high-milk-fat diet (HMFD) plus/minus EMPA (@0.01%) for 12-wk. Kidney weights and glomerular filtration rate were slightly increased by EMPA in the TH mice. Glomerular feature analysis by unsupervised clustering revealed sexually dimorphic clustering, and one unique cluster relating to EMPA. Periodic acid Schiff (PAS) positive areas, reflecting basement membranes and mesangium were slightly reduced by EMPA. Phasor-fluorescent life-time imaging (FLIM) of free-to-protein bound NADH in cortex showed a marginally greater reliance on oxidative phosphorylation with EMPA. Overall, net urine sodium, glucose, and albumin were slightly increased by EMPA. In TH, EMPA reduced the sodium phosphate cotransporter, type 2 (NaPi-2), but increased sodium hydrogen exchanger, type 3 (NHE3). These changes were absent or blunted in SW. EMPA led to changes in urine exosomal microRNA profile including, in females, enhanced levels of miRs 27a-3p, 190a-5p, and 196b-5p. Network analysis revealed "cancer pathways" and "FOXO signaling" as the major regulated pathways. Overall, EMPA treatment to prediabetic mice with limited renal disease resulted in modifications in renal metabolism, structure, and transport, which may preclude and underlie protection against kidney disease with developing T2D.NEW & NOTEWORTHY Renal protection afforded by sodium glucose transporter, type 2 inhibitors (SGLT2i), e.g., empagliflozin (EMPA) involves complex intertwined mechanisms. Using a novel mouse model of obesity with insulin resistance, the TallyHo/Jng (TH) mouse on a high-milk-fat diet (HMFD), we found subtle changes in metabolism including altered regulation of sodium transporters that line the renal tubule. New potential epigenetic determinants of metabolic changes relating to FOXO and cancer signaling pathways were elucidated from an altered urine exosomal microRNA signature.

Effect of topical testosterone on pre-diabetes and diabetes

Overview of: Bhasin S, Lincoff AM, Nissen SE, et al. Effect of testosterone on progression from prediabetes to diabetes in men with hypogonadism: a substudy of the TRAVERSE randomized clinical trial. JAMA Intern Med. 2024. doi: 10.1001/jamainternmed.2023.7862. [Epub ahead of print 5 February 2024].

Predictive factors and the management of hyperglycemia in patients with acromegaly and Cushing's disease receiving pasireotide treatment: post hoc analyses from the SOM230B2219 study

Introduction

Pasireotide, a somatostatin receptor ligand, is approved for treating acromegaly and Cushing's disease (CD). Hyperglycemia during treatment can occur because of the drug's mechanism of action, although treatment discontinuation is rarely required. The prospective, randomized, Phase IV SOM230B2219 (NCT02060383) trial was designed to assess optimal management of pasireotide-associated hyperglycemia. Here, we investigated predictive factors for requiring antihyperglycemic medication during pasireotide treatment.

Methods

Participants with acromegaly or CD initiated long-acting pasireotide 40 mg/28 days intramuscularly (acromegaly) or pasireotide 600 μg subcutaneously twice daily during pre-randomization (≤16 weeks). Those who did not need antihyperglycemic medication, were managed with metformin, or received insulin from baseline entered an observational arm ending at 16 weeks. Those who required additional/alternative antihyperglycemic medication to metformin were randomized to incretin-based therapy or insulin for an additional 16 weeks. Logistic-regression analyses evaluated quantitative and qualitative factors for requiring antihyperglycemic medication during pre-randomization.

Results

Of 190 participants with acromegaly and 59 with CD, 88 and 15, respectively, did not need antihyperglycemic medication; most were aged <40 years (acromegaly 62.5%, CD 86.7%), with baseline glycated hemoglobin (HbA1c) <6.5% (<48 mmol/mol; acromegaly 98.9%, CD 100%) and fasting plasma glucose (FPG) <100 mg/dL (<5.6 mmol/L; acromegaly 76.1%, CD 100%). By logistic regression, increasing baseline HbA1c (odds ratio [OR] 3.6; P=0.0162) and FPG (OR 1.0; P=0.0472) and history of diabetes/pre-diabetes (OR 3.0; P=0.0221) predicted receipt of antihyperglycemic medication in acromegaly participants; increasing baseline HbA1c (OR 12.6; P=0.0276) was also predictive in CD participants. Investigator-reported hyperglycemia-related adverse events were recorded in 47.9% and 54.2% of acromegaly and CD participants, respectively, mainly those with diabetes/pre-diabetes.

Conclusion

Increasing age, HbA1c, and FPG and pre-diabetes/diabetes were associated with increased likelihood of requiring antihyperglycemic medication during pasireotide treatment. These risk factors may be used to identify those who need more vigilant monitoring to optimize outcomes during pasireotide treatment.

Effect of cinnamon spice on continuously monitored glycemic response in adults with prediabetes: a 4-week randomized controlled crossover trial

BACKGROUND

Previous clinical studies showing that cinnamon spice lowers blood glucose concentrations had inconsistent results.

OBJECTIVES

To determine the effect of daily cinnamon spice supplementation in an amount commonly used for seasoning on glucose concentrations in adults with obesity and prediabetes.

METHODS

Following a 2-wk run-in period of maintaining a low polyphenol/fiber diet, 18 participants with obesity and prediabetes underwent a 10-wk randomized, controlled, double-blind, crossover trial (mean age 51.1 y; mean fasting plasma glucose 102.9 mg/dL). The participants were randomly assigned to take cinnamon (4 g/d) or placebo for 4-wk, followed by a 2-wk washout period, and then crossed over to the other intervention for an additional 4-wk. Glucose changes were measured with continuous glucose monitoring. Oral glucose tolerance testing immediately following ingestion of cinnamon or placebo was performed at 4-time points to assess their acute effects both at the baseline and end of each intervention phase. Digestive symptom logs were obtained daily.

RESULTS

There were 694 follow-up days with 66,624 glucose observations. When compared with placebo, 24-h glucose concentrations were significantly lower when cinnamon was administered [mixed-models; effect size (ES) = 0.96; 95 % confidence interval (CI): -2.9, -1.5; P < 0.001]. Similarly, the mean net-area-under-the-curve (netAUC) for glucose was significantly lower than for placebo when cinnamon was given (over 24 h; ES = -0.66; 95 % CI: 2501.7, 5412.1, P = 0.01). Cinnamon supplementation resulted in lower glucose peaks compared with placebo (Δpeak 9.56 ± 9.1 mg/dL compared with 11.73 ± 8.0 mg/dL; ES = -0.57; 95 % CI: 0.8, 3.7, P = 0.027). Glucose-dependent-insulinotropic-polypeptide concentrations increased during oral glucose tolerance testing + cinnamon testing (mixed-models; ES = 0.51; 95 % CI: 1.56, 100.1, P = 0.04), whereas triglyceride concentrations decreased (mixed-models; ES = 0.55; 95 % CI: -16.0, -1.6, P = 0.02). Treatment adherence was excellent in both groups (cinnamon: 97.6 ± 3.4 % compared with placebo: 97.9 ± 3.7 %; ES = -0.15; 95 % CI: -1.8, 0.2, P = 0.5). No differences were found in digestive symptoms (abdominal pain, borborygmi, bloating, excess flatus, and stools/day) between cinnamon and placebo groups.

CONCLUSIONS

Cinnamon, a widely available and low-cost supplement, may contribute to better glucose control when added to the diet in people who have obesity-related prediabetes. This trial was registered at clinicaltrials.gov as NCT04342624.

Baicalin ameliorates insulin resistance and regulates hepatic glucose metabolism via activating insulin signaling pathway in obese pre-diabetic mice

BACKGROUND

Diabetes belongs to the most prevalent metabolic diseases worldwide, which is featured with insulin resistance, closely associated with obesity and urgently needs to be treated. Baicalin, belonging to natural flavonoids, has been reported to inhibit oxidative stress or inflammatoin.

PURPOSE

This study investigated the properties of baicalin on modulating abnormal glucolipid metabolism, as well as the underlying in-vitro and in-vivo mechanisms.

METHODS

Insulin-resistant (IR)-HepG2 cells were stimulated by dexamethasone (20 µM) and high glucose (50 mM) for 48 h and incubated with or without baicalin or metformin for another 16 h. Male C57BL/6 J mice were fed with a high-fat diet (HFD, 60 % kcal% fat) during the total 14 weeks. Obese mice were then administered with baicalin (50 and 100 mg/kg) or vehicle solution everyday through oral gavage during the last 4-week period. Moreover, baicalin metabolisms in vitro and in vivo were determined using UPLC/MS/MS to study its metabolism situation.

RESULTS

Exposure to dexamethasone and high glucose damaged the abilities of glycogen synthesis and glucose uptake with elevated oxidative stress and increased generation levels of advanced glycation end-products (AGEs) in HepG2 cells. These impairments were basically reversed by baicalin treatment. Four-week oral administration with baicalin ameliorated hyperglycemia and dyslipidemia in HFD-induced obese and pre-diabetic mice. Downregulation of IRS/PI3K/Akt signaling pathway accomplished with reduced GLUT4 expression and enhanced GSK-3β activity was observed in insulin resistant HepG2 cells as well as liver tissues from pre-diabetic mice; and such effect was prevented by baicalin. Moreover, baicalin and its matabolites were detected in IR-HepG2 cells and mouse plasma.

CONCLUSION

The study illustrated that baicalin alleviated insulin resistance by activating insulin signaling pathways and inhibiting oxidative stress and AGEs production, revealing the potential of baicalin to be a therapeutic natural flavonoid against hepatic insulin and glucose-lipid metabolic disturbance in pre-diabetes accompanied with obesity.

Carnosine supplementation improves glucose control in adults with pre-diabetes and type 2 diabetes: A randomised controlled trial

BACKGROUND AND AIMS

Type 2 diabetes (T2DM) is a major cause of morbidity and mortality globally. Carnosine, a naturally occurring dipeptide, has anti-inflammatory, antioxidant, and anti-glycating effects, with preliminary evidence suggesting it may improve important chronic disease risk factors in adults with cardiometabolic conditions.

METHODS AND RESULTS

In this randomised controlled trial, 43 adults (30%F) living with prediabetes or T2DM consumed carnosine (2 g) or a matching placebo daily for 14 weeks to evaluate its effect on glucose metabolism assessed via a 2-h 75 g oral glucose tolerance test. Secondary outcomes included body composition analysis by dual energy x-ray absorptiometry (DEXA), calf muscle density by pQCT, and anthropometry. Carnosine supplementation decreased blood glucose at 90 min (-1.31 mmol/L; p = 0.02) and 120 min (-1.60 mmol/L, p = 0.02) and total glucose area under the curve (-3.30 mmol/L; p = 0.04) following an oral glucose tolerance test. There were no additional changes in secondary outcomes. The carnosine group results remained significant before and after adjustment for age, sex, and change in weight (all>0.05), and in further sensitivity analyses accounting for missing data. There were no significant changes in insulin levels.

CONCLUSION

This study provides preliminary support for larger trials evaluating carnosine as a potential treatment for prediabetes and the initial stages of T2DM. Likely mechanisms may include changes to hepatic glucose output explaining the observed reduction in blood glucose without changes in insulin secretion following carnosine supplementation.

Protocol for a randomized placebo-controlled clinical trial using pure palmitoleic acid to ameliorate insulin resistance and lipogenesis in overweight and obese subjects with prediabetes

Palmitoleic acid (POA), a nonessential, monounsaturated omega-7 fatty acid (C16:1n7), is a lipid hormone secreted from adipose tissue and has beneficial effects on distant organs, such as the liver and muscle. Interestingly, POA decreases lipogenesis in toxic storage sites such as the liver and muscle, and paradoxically increases lipogenesis in safe storage sites, such as adipose tissue. Furthermore, higher POA levels in humans are correlated with better insulin sensitivity, an improved lipid profile, and a lower incidence of type-2 diabetes and cardiovascular pathologies, such as myocardial infarction. In preclinical animal models, POA improves glucose intolerance, dyslipidemia, and steatosis of the muscle and liver, while improving insulin sensitivity and secretion. This double-blind placebo-controlled clinical trial tests the hypothesis that POA increases insulin sensitivity and decreases hepatic lipogenesis in overweight and obese adult subjects with pre-diabetes. Important to note, that this is the first study ever to use pure (>90%) POA with < 0.3% palmitic acid (PA), which masks the beneficial effects of POA. The possible positive findings may offer a therapeutic and/or preventative pathway against diabetes and related immunometabolic diseases.

Akt Signaling and Nitric Oxide Synthase as Possible Mediators of the Protective Effect of N-acetyl-L-cysteine in Prediabetes Induced by Sucrose

The aim of this work was to evaluate possible mechanisms involved in the protective effect of N-acetyl-L-cysteine (NAC) on hepatic endocrine-metabolic, oxidative stress, and inflammatory changes in prediabetic rats. For that, normal male Wistar rats (60 days old) were fed for 21 days with 10% sucrose in their drinking water and 5 days of NAC administration (50 mg/kg, i.p.) and thereafter, we determined: serum glucose, insulin, transaminases, uric acid, and triglyceride levels; hepatic fructokinase and glucokinase activities, glycogen content, lipogenic gene expression; enzymatic and non-enzymatic oxidative stress, insulin signaling pathway, and inflammatory markers. Results showed that alterations evinced in sucrose-fed rats (hypertriglyceridemia, hyperinsulinemia, and high liver fructokinase activity together with increased liver lipogenic gene expression and oxidative stress and inflammatory markers) were prevented by NAC administration. P-endothelial nitric oxide synthase (P-eNOS)/eNOS and pAKT/AKT ratios, decreased by sucrose ingestion, were restored after NAC treatment. In conclusion, the results suggest that NAC administration improves glucose homeostasis, oxidative stress, and inflammation in prediabetic rats probably mediated by modulation of the AKT/NOS pathway. Administration of NAC may be an effective complementary strategy to alleviate or prevent oxidative stress and inflammatory responses observed in type 2 diabetes at early stages of its development (prediabetes).

Supplementation of papaya leaf juice has beneficial effects on glucose homeostasis in high fat/high sugar-induced obese and prediabetic adult mice

Prediabetes is characterized by a cluster of glycemic parameters higher than normal but below the threshold of type 2 diabetes mellitus (T2DM). In recent years, phytochemical-rich plant extracts have gained popularity as therapeutic agents for metabolic disorders. This study investigated the effects of papaya leaf (PL) juice supplementation on blood glucose levels in diet-induced obese and prediabetic adult mice. B65JL F1 mice (n = 20) at 12-14 months old were fed a high fat/sugar diet (HFHS) for 120 days. Mice were switched to restricted rodent chow of 3 g feed/30 g body weight/day, supplemented with 3 g/100 mL PL juice for 30 days. HFHS diet remarkably increased fasting plasma glucose levels from 114 ± 6.54 mg/dL to 192.7 ± 10.1 mg/dL and body weight from 32.5 ± 1.6 to 50.3 ± 4.1 g. HFHS diet results in hyperglycemia, insulin resistance, hyperlipidemia, and liver steatosis. The combination of PL juice and restricted diet significantly reduced body weight and fasting blood glucose levels to 43.75 ± 1.4 g and 126.25 ± 3.2 mg/dl, respectively. Moreover, PL juice with a restricted diet significantly improved lipid profile: cholesterol from 204 to 150 mg/dL, LDL-c from 110.4 to 50 mg/dL, and triglyceride from 93.7 to 60 mg/dL. Additionally, PL juice combined with a restricted diet significantly reduced adiposity, reversed fatty liver, and restored skeletal muscle Glut4 and phosphorylated (p-AKT (ser473). This study demonstrated that supplementation of PL juice with a restricted diet was more effective than a restricted diet alone in reversing major symptoms related to prediabetic and obesity conditions.

Liraglutide 3.0 mg (Saxenda©) for Weight Loss and Remission of Pre-Diabetes. Real-World Clinical Evaluation of Effectiveness among Patients Awaiting Bariatric Surgery

OBJECTIVE

The effectiveness of liraglutide 3.0 mg (Saxenda) therapy to induce weight loss among obese patients prior to bariatric surgery remains uncertain.

METHODS

Clinical data was retrospectively obtained from patients with prediabetes (HbA1c 42-47 mmol/mol) and selected patients on the waiting list for bariatric surgery at the Royal Derby Hospital. Clinical data was collected retrospectively at 6, 12, 26 and 52 week intervals. The outcomes included mean weight change, proportion of patients achieving ≥ 5% and ≥ 10% weight loss and achieving HbA1c reduction to normal range values.

RESULTS

Fifty patients (mean age of 46.2 ± 10.5 years; 76% female and 94% had Class III obesity) who completed 52 and/or 26 weeks of treatment were included. Liraglutide 3.0 mg produced a consistent and statistically significant reduction in weight (kg), BMI (kg/m2) and HbA1c (mmol/mol) across all four time intervals. Average ± SD reduction for weight, BMI and HbA1c respectively at 26 weeks were: -10.9 ± 9.1 (P < 0.01), -3.67 ± 3.5 (P < 0.01), -4.7 IQR 4.95 (P < 0.001), and at 52 weeks were: -14 ± 9.2 kg (P < 0.001), -4.64 ± 4.0 (P < 0.001 and -5.5 IQR 4 (P = 0.009). 85.7% and 33.3% of patients achieved ≥ 5% and 10% weight loss target respectively at 52 weeks. 92.3% and 72.2% achieved remission of pre-diabetes by 6 and 12 months respectively. Liraglutide 3.0 mg was well-tolerated with only 10% discontinuing medication due to tolerability issues.

CONCLUSION

Liraglutide 3.0 mg, with lifestyle management, reduced weight and improved glycaemic control. These results support liraglutide's application in certain high-risk populations, including patients waiting for bariatric surgical intervention.

Liraglutide treatment for the prevention of glucose tolerance deterioration in women with prior gestational diabetes mellitus: A 52-week randomized controlled clinical trial

AIM

We investigated the effect of 52-week treatment with liraglutide, a glucagon-like peptide 1 receptor agonist, on glucose tolerance and incretin effect in women with previous gestational diabetes mellitus (pGDM).

MATERIALS AND METHODS

Women with overweight/obesity and pGDM were randomized to once daily subcutaneous liraglutide 1.8 mg or placebo for 52 weeks. Participants underwent oral glucose tolerance test (OGTT) and isoglycaemic intravenous glucose infusion at baseline and at 52 weeks, and an additional OGTT after the drug wash-out.

RESULTS

In total, 104 women [age: mean ± SD, 38 ± 5 years; fasting plasma glucose (FPG): 5.5 ± 0.4 mmol/L; glycated haemoglobin (HbA1c): 33 ± 4 mmol/mol, bodyweight: 88.2 ± 14.8 kg, body mass index: 31.1 ± 4.3 kg/m2 ] were assigned to liraglutide (n = 49) or placebo (n = 55). Estimated treatment difference (ETD) for area under curve during OGTT was -173 (95% confidence interval -250 to -97) mmol/L × min, p < .0001, but after wash-out the difference disappeared [ETD 58 (-30 to 146) mmol/L × min, p = .536]. Liraglutide reduced FPG [ETD -0.2 (-0.4 to -0.1) mmol/L, p = .018], HbA1c [-2.2 (-3.5 to -0.8) mmol/mol, p = .018] and bodyweight [-3.9 (-6.2 to -1.6) kg, p = .012]. No change in the incretin effect was observed. The number of women with prediabetes was reduced from 64% to 10% with liraglutide vs. 50% with placebo [adjusted odds ratio 0.10 (0.03-0.32), p = .002].

CONCLUSIONS

Treatment with liraglutide for 52 weeks improved glucose tolerance, FPG, HbA1c and bodyweight in women with overweight/obesity and pGDM. Progression to prediabetes while on drug was markedly reduced, but after a 1-week drug wash-out, the effect was lost.

Metformin prescription for U.S. veterans with prediabetes, 2010-2019

Affecting an estimated 88 million Americans, prediabetes increases the risk for developing type 2 diabetes mellitus (T2DM), and independently, cardiovascular disease, retinopathy, nephropathy, and neuropathy. Nevertheless, little is known about the use of metformin for diabetes prevention among patients in the Veterans Health Administration, the largest integrated healthcare system in the U.S. This is a retrospective observational cohort study of the proportion of Veterans with incident prediabetes who were prescribed metformin at the Veterans Health Administration from October 2010 to September 2019. Among 1,059,605 Veterans with incident prediabetes, 12,009 (1.1%) were prescribed metformin during an average 3.4 years of observation after diagnosis. Metformin prescribing was marginally higher (1.6%) among those with body mass index (BMI) ≥35 kg/m2, age <60 years, HbA1c≥6.0%, or those with a history of gestational diabetes, all subgroups at a higher risk for progression to T2DM. In a multivariable model, metformin was more likely to be prescribed for those with BMI ≥35 kg/m2 incidence rate ratio [IRR] 2.6 [95% confidence intervals (CI): 2.1-3.3], female sex IRR, 2.4 [95% CI: 1.8-3.3], HbA1c≥6% IRR, 1.93 [95% CI: 1.5-2.4], age <60 years IRR, 1.7 [95% CI: 1.3-2.3], hypertriglyceridemia IRR, 1.5 [95% CI: 1.2-1.9], hypertension IRR, 1.5 [95% CI: 1.1-2.1], Major Depressive Disorder IRR, 1.5 [95% CI: 1.1-2.0], or schizophrenia IRR, 2.1 [95% CI: 1.2-3.8]. Over 20% of Veterans with prediabetes attended a comprehensive structured lifestyle modification clinic or program. Among Veterans with prediabetes, metformin was prescribed to 1.1% overall, a proportion that marginally increased to 1.6% in the subset of individuals at highest risk for progression to T2DM.

Weight Loss-Independent Effect of Liraglutide on Insulin Sensitivity in Individuals With Obesity and Prediabetes

Metabolic effects of glucagon-like peptide 1 (GLP-1) receptor agonists are confounded by weight loss and not fully recapitulated by increasing endogenous GLP-1. We tested the hypothesis that GLP-1 receptor (GLP-1R) agonists exert weight loss-independent, GLP-1R-dependent effects that differ from effects of increasing endogenous GLP-1. Individuals with obesity and prediabetes were randomized to receive for 14 weeks the GLP-1R agonist liraglutide, a hypocaloric diet, or the dipeptidyl peptidase 4 (DPP-4) inhibitor sitagliptin. The GLP-1R antagonist exendin(9-39) and placebo were administered in a two-by-two crossover study during mixed-meal tests. Liraglutide and diet, but not sitagliptin, caused weight loss. Liraglutide improved insulin sensitivity measured by HOMA for insulin resistance (HOMA-IR), the updated HOMA model (HOMA2), and the Matsuda index after 2 weeks, prior to weight loss. Liraglutide decreased fasting and postprandial glucose levels, and decreased insulin, C-peptide, and fasting glucagon levels. In contrast, diet-induced weight loss improved insulin sensitivity by HOMA-IR and HOMA2, but not the Matsuda index, and did not decrease glucose levels. Sitagliptin increased endogenous GLP-1 and GIP values without altering insulin sensitivity or fasting glucose levels, but decreased postprandial glucose and glucagon levels. Notably, sitagliptin increased GIP without altering weight. Acute GLP-1R antagonism increased glucose levels in all groups, increased the Matsuda index and fasting glucagon level during liraglutide treatment, and increased endogenous GLP-1 values during liraglutide and sitagliptin treatments. Thus, liraglutide exerts rapid, weight loss-independent, GLP-1R-dependent effects on insulin sensitivity that are not achieved by increasing endogenous GLP-1.

ARTICLE HIGHLIGHTS

Metabolic benefits of glucagon-like peptide 1 (GLP-1) receptor agonists are confounded by weight loss and are not fully achieved by increasing endogenous GLP-1 through dipeptidyl peptidase 4 (DPP-4) inhibition. We investigated weight loss-independent, GLP-1 receptor (GLP-1R)-dependent metabolic effects of liraglutide versus a hypocaloric diet or the DPP-4 inhibitor sitagliptin. GLP-1R antagonism with exendin(9-39) was used to assess GLP-1R-dependent effects during mixed meals. Liraglutide improved insulin sensitivity and decreased fasting and postprandial glucose prior to weight loss, and these benefits were reversed by exendin(9-39). GLP-1R agonists exert rapid, weight loss-independent, GLP-1R-dependent effects on insulin sensitivity not achieved by increasing endogenous GLP-1.

Berberine attenuates cognitive dysfunction and hippocampal apoptosis in rats with prediabetes

The cognitive dysfunction caused by prediabetes causes great difficulties in human life, and the terrible thing is that the means to prevent the occurrence of this disease are very limited at present, Berberine has shown the potential to treat diabetes and cognitive dysfunction, but it still needs to be further explored to clarify the mechanism of its therapeutic effect. Therefore, the aim of this study was to investigate the effects and mechanisms of Berberine on prediabetes-induced cognitive dysfunction. Prediabetes rat model was induced by a high-fat diet and a normal diet was used as a control. They were fed for 20 weeks. At week 13, the model rats were given 100 mg/kg Berberine by gavage for 7 weeks. The cognitive function of rats was observed. At the same time, OGTT, fasting blood glucose, blood lipids, insulin and other metabolic parameters, oxidative stress, and apoptosis levels were measured. The results showed that the model rats showed obvious glucose intolerance, elevated blood lipids, and insulin resistance, and the levels of oxidative stress and apoptosis were significantly increased. However, after the administration of Berberine, the blood glucose and lipid metabolism of prediabetic rats were significantly improved, and the oxidative stress level and apoptosis level of hippocampal tissue were significantly reduced. In conclusion, Berberine can alleviate the further development of diabetes in prediabetic rats, reduce oxidative stress and apoptosis in hippocampal tissue, and improve cognitive impairment in prediabetic rats.

Efficacy and safety of bempedoic acid among patients with and without diabetes: prespecified analysis of the CLEAR Outcomes randomised trial

BACKGROUND

Statins reduce LDL cholesterol and cardiovascular events among those with or without diabetes but have been reported to increase new-onset diabetes. The CLEAR Outcomes trial demonstrated that bempedoic acid reduced the risk of major adverse cardiovascular events among statin-intolerant patients at high cardiovascular risk. In this prespecified analysis, our dual aims were to evaluate the cardiovascular benefits of bempedoic acid, an ATP-citrate lyase inhibitor, in individuals with diabetes, and to evaluate the risk of new-onset diabetes and HbA1c among those without diabetes in the CLEAR Outcomes trial.

METHODS

CLEAR Outcomes was a randomised, double-blind, placebo-controlled trial conducted across 1250 primary care and outpatient sites in 32 countries. Patients with or without cardiovascular disease who were unwilling or unable to take guideline-recommended doses of statins and an LDL cholesterol of 2·59 mmol/L or more were randomly assigned (1:1) in a double-blinded manner to either bempedoic acid 180 mg once per day or placebo. In this prespecified analysis, the efficacy endpoint was a time-to-event analysis of four-component major adverse cardiovascular event (MACE-4), which is the composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularisation, using the intention-to-treat population stratified by baseline glycaemia status. The prespecified analysis of risk of new-onset diabetes and HbA1c increase was evaluated in patients without diabetes at baseline. The CLEAR Outcomes trial was completed on Nov 7, 2022, and is registered with ClinicalTrials.gov (NCT02993406).

FINDINGS

Between Dec 22, 2016, and Nov 7, 2022, 13 970 patients were screened and randomly assigned; 6373 (45·6%) with diabetes, 5796 (41·5%) with prediabetes, and 1801 (12·9%) with normoglycaemia. Over a median of 3·4 years follow up, patients with diabetes had significant relative and absolute cardiovascular risk reductions in MACE-4 endpoints with bempedoic acid (HR 0·83; 95% CI 0·72-0·95; absolute risk reduction of 2·4%) compared to placebo, with no statistical evidence of effect modification across glycaemic strata (interaction p=0·42). The proportion of patients who developed new-onset diabetes were similar between the bempedoic acid and placebo groups, with 429 of 3848 (11·1%) with bempedoic acid versus 433 of 3749 (11·5%) with placebo (HR 0·95; 95% CI 0·83-1·09). HbA1c concentrations at month 12 and the end of the study were similar between randomised groups in patients who had prediabetes and normoglycaemia. Placebo-corrected LDL cholesterol concentrations and high-sensitivity C-reactive protein at 6 months were reduced in each glycaemic stratum (diabetes, prediabtes, and normoglycaemia) for patients randomly assigned to bempedoic acid (all p<0·001).

INTERPRETATION

Among patients with diabetes, bempedoic acid reduces LDL cholesterol and high-sensitivity C-reactive protein and risk of cardiovascular events. Patients without diabetes had no increase in new-onset diabetes or worsening HbA1c with bempedoic acid. The efficacy and cardiometabolic safety profile of bempedoic acid makes it a clinical option for those with and without diabetes.

FUNDING

Esperion Therapeutics.

Effect of denosumab on glucose metabolism in postmenopausal osteoporotic women with prediabetes: a study protocol for a 12-month multicenter, open-label, randomized controlled trial

BACKGROUND

Participants with prediabetes are at a high risk of developing type 2 diabetes (T2D). Recent studies have suggested that blocking the receptor activator of nuclear factor-κB ligand (RANKL) may improve glucose metabolism and delay the development of T2D. However, the effect of denosumab, a fully human monoclonal antibody that inhibits RANKL, on glycemic parameters in the prediabetes population is uncertain. We aim to examine the effect of denosumab on glucose metabolism in postmenopausal women with osteoporosis and prediabetes.

METHODS

This is a 12-month multicenter, open-label, randomized controlled trial involving postmenopausal women who have been diagnosed with both osteoporosis and prediabetes. Osteoporosis is defined by the World Health Organization (WHO) as a bone mineral density T score of ≤ - 2.5, as measured by dual-energy X-ray absorptiometry (DXA). Prediabetes is defined as (i) a fasting plasma glucose level of 100-125 mg/dL, (ii) a 2-hour plasma glucose level of 140-199 mg/dL, or (iii) a glycosylated hemoglobin A1c (HbA1c) level of 5.7-6.4%. A total of 346 eligible subjects will be randomly assigned in a 1:1 ratio to receive either subcutaneous denosumab 60 mg every 6 months or oral alendronate 70 mg every week for 12 months. The primary outcome is the change in HbA1c levels from baseline to 12 months. Secondary outcomes include changes in fasting and 2-hour blood glucose levels, serum insulin levels, C-peptide levels, and insulin sensitivity from baseline to 12 months, and the incidence of T2D at the end of the study. Follow-up visits will be scheduled at 3, 6, 9, and 12 months.

DISCUSSION

This study aims to provide evidence on the efficacy of denosumab on glucose metabolism in postmenopausal women with osteoporosis and prediabetes. The results derived from this clinical trial may provide insight into the potential of denosumab in preventing T2D in high-risk populations.

TRIAL REGISTRATION

This study had been registered in the Chinese Clinical Trials Registry.

REGISTRATION NUMBER

ChiCTR2300070789 on April 23, 2023. https://www.chictr.org.cn .

The Effectiveness of Shared Decision-making for Diabetes Prevention: 24- and 36-Month Results From the Prediabetes Informed Decision and Education (PRIDE) Trial

OBJECTIVE

We conducted a cluster-randomized, shared decision-making (SDM) trial offering lifestyle change, metformin, or both options, to adults at risk for diabetes in a primary care network (n = 20 practices).

RESEARCH DESIGN AND METHODS

We used propensity score matching to identify control patients and used electronic health record data to compare weight loss at 24 and 36 months of follow-up and diabetes incidence at 36 months of follow-up.

RESULTS

In adjusted post hoc analyses, SDM participants (n = 489) maintained modestly greater 24-month weight loss of -3.1 lb and 36-month weight loss of -2.7 lb versus controls (n = 1,430, both comparisons P < 0.001). SDM participants who chose both lifestyle change and metformin sustained weight loss at 36 months of -4.1 lb (P < 0.001 vs. controls). We found no differences in incident diabetes (15% of SDM participants, 14% of control participants; P = 0.64).

CONCLUSIONS

This is one of the first studies to demonstrate weight loss maintenance up to 36 months after diabetes prevention SDM.

Metformin restores prohormone processing enzymes and normalizes aberrations in secretion of proinsulin and insulin in palmitate-exposed human islets

AIM

To elucidate how proinsulin synthesis and insulin was affected by metformin under conditions of nutrient overstimulation.

MATERIALS AND METHODS

Isolated human pancreatic islets from seven donors were cultured at 5.5 mmol/L glucose and 0.5 mmol/L palmitate for 12, 24 or 72 h. Metformin (25 μmol/L) was introduced after initial 12 h with palmitate. Proinsulin and insulin were measured. Expression of prohormone convertase 1/3 (PC1/3) and carboxypeptidase E (CPE), was determined by western blot. Adolescents with obesity, treated with metformin and with normal glucose tolerance (n = 5), prediabetes (n = 14), or type 2 diabetes (T2DM; n = 7) were included. Fasting proinsulin, insulin, glucose, 2-h glucose and glycated haemoglobin were measured. Proinsulin/insulin ratio (PI/I) was calculated.

RESULTS

In human islets, palmitate treatment for 12 and 24 h increased proinsulin and insulin proportionally. After 72 h, proinsulin but not insulin continued to increase which was coupled with reduced expression of PC1/3 and CPE. Metformin normalized expression of PC1/3 and CPE, and proinsulin and insulin secretion. In adolescents with obesity, before treatment, fasting proinsulin and insulin concentrations were higher in subjects with T2DM than with normal glucose tolerance. PI/I was reduced after metformin treatment in subjects with T2DM as well as in subjects with prediabetes, coupled with reduced 2-h glucose and glycated haemoglobin.

CONCLUSIONS

Metformin normalized proinsulin and insulin secretion after prolonged nutrient-overstimulation, coupled with normalization of the converting enzymes, in isolated islets. In adolescents with obesity, metformin treatment was associated with improved PI/I, which was coupled with improved glycaemic control.

Combinational application of the natural products 1-deoxynojirimycin and morin ameliorates insulin resistance and lipid accumulation in prediabetic mice

BACKGROUND

Prediabetes, a stage characterized by chronic inflammation, obesity and insulin resistance. Morin and 1-deoxynojirimycin (DNJ) are natural flavonoids and alkaloids extracted from Morus nigra L., exhibiting anti-hyperglycemic efficacy. However, the benefits of DNJ are shadowed by the adverse events, and the mechanism of morin in anti-diabetes remains under investigation.

PURPOSE

In this study, the combinational efficacy and mechanisms of DNJ and morin in ameliorating insulin resistance and pre-diabetes were investigated.

METHODS

The mice model with prediabetes and Alpha mouse liver-12 (AML-12) cell model with insulin resistance were established. The anti-prediabetic efficacy of the drug combination was determined via analyzing the blood glucose, lipid profiles and inflammatory factors. The application of network pharmacology provided guidance for the research mechanism.

RESULTS

In our study, the intervention of morin ameliorated the insulin resistance via activating the Peroxisome proliferator-activated receptor γ (PPARγ). However, PPARγ activation leaded to the lipid accumulation in prediabetic mice. The combination of 5 mg/kg dose of DNJ and 25 mg/kg morin effectively hindered the progression of T2DM by 87.56%, which was achieved via inhibition of Suppressors of cytokine signaling 3 (SOCS3) and promotion of PPARγ as well as SOCS2 expression. Furthermore, this treatment exhibited notable capabilities in combating dyslipidemia and adipogenesis, achieved by suppressing the Cluster of differentiation 36/ Sterol-regulatory element binding proteins-1/ Fatty acid synthetase (CD36/Serbp1/Fas) signaling.

CONCLUSION

This research confirmed that the drug combination of DNJ and morin in ameliorating insulin resistance and lipid accumulation, and revealed the potential mechanisms. In summary, the combination of DNJ and morin is an underlying alternative pharmaceutical composition in T2DM prevention.

Tirzepatide reduces the predicted risk of developing type 2 diabetes in people with obesity or overweight: Post hoc analysis of the SURMOUNT-1 trial

AIM

We assessed the impact of tirzepatide on 10-year predicted risk of developing type 2 diabetes (T2D) among participants in the SURMOUNT-1 trial.

MATERIALS AND METHODS

In this post hoc analysis of SURMOUNT-1, the Cardiometabolic Disease Staging risk engine was used to calculate the 10-year predicted risk of T2D at baseline, week 24 and week 72 among participants randomized to receive 5, 10, or 15 mg tirzepatide or placebo. Mean changes in risk scores from baseline to weeks 24 and 72 were compared between tirzepatide and placebo groups. Subgroup analyses were conducted based on participants' glycaemic status and body mass index at baseline.

RESULTS

Mean baseline T2D predicted risk scores did not differ between tirzepatide and placebo groups (range: 22.9%-24.3%). At week 72, mean absolute T2D predicted risk score reductions were significantly greater in tirzepatide groups (5 mg, 12.4%; 10 mg, 14.4%; 15 mg, 14.7%) versus placebo (0.7%). At week 72, median relative predicted risk reductions following tirzepatide treatment ranged from 60.3% to 69.0%. For participants with and without prediabetes, risk reductions were significantly greater in tirzepatide groups versus placebo. At week 72, participants with prediabetes (range: 16.0%-20.3%) had greater mean risk score reductions from baseline versus those without prediabetes (range: 10.1%-11.3%). Across body mass index subgroups, mean reductions from baseline were significantly greater in tirzepatide groups versus placebo.

CONCLUSION

Tirzepatide treatment significantly reduced the 10-year predicted risk of developing T2D compared with placebo in participants with obesity or overweight, regardless of baseline glycaemic status.

Carnosine Did Not Affect Vascular and Metabolic Outcomes in Patients with Prediabetes and Type 2 Diabetes: A 14-Week Randomized Controlled Trial

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of morbidity and mortality in patients with prediabetes and type 2 diabetes mellitus (T2DM). Carnosine has been suggested as a potential approach to reduce ASCVD risk factors. However, there is a paucity of human data. Hence, we performed a 14-week double-blind randomized placebo-controlled trial to determine whether carnosine compared with placebo improves vascular and metabolic outcomes in individuals with prediabetes and T2DM. In total, 49 patients with prediabetes and T2DM with good glycemic control were randomly assigned either to receive 2 g/day carnosine or matching placebo. We evaluated endothelial dysfunction, arterial stiffness, lipid parameters, blood pressure, heart rate, hepatic and renal outcomes before and after the intervention. Carnosine supplementation had no effect on heart rate, peripheral and central blood pressure, endothelial function (logarithm of reactive hyperemia (LnRHI)), arterial stiffness (carotid femoral pulse wave velocity (CF PWV)), lipid parameters, liver fibroscan indicators, liver transient elastography, liver function tests, and renal outcomes compared to placebo. In conclusion, carnosine supplementation did not improve cardiovascular and cardiometabolic risk factors in adults with prediabetes and T2DM with good glycemic control. Therefore, it is improbable that carnosine supplementation would be a viable approach to mitigating the ASCVD risk in these populations. The trial was registered at clinicaltrials.gov (NCT02917928).

The Emerging Role of Prediabetes and Its Management: Focus on L-Arginine and a Survey in Clinical Practice

The worldwide impressive growth of metabolic disorders observed in the last decades, especially type 2 diabetes mellitus and obesity, has generated great interest in the potential benefits of early identification and management of patients at risk. In this view, prediabetes represents a high-risk condition for the development of type 2 diabetes mellitus and cardiovascular diseases, and an ideal target to intercept patients before they develop type 2 diabetes gaining a prominent role even in international guidelines. For prediabetic individuals, lifestyle modification is the cornerstone of diabetes prevention, with evidence of about 50% relative risk reduction. Accumulating data also show potential benefits from pharmacotherapy. In this context, the only available data pertain to metformin as a pharmaceutical drug and vitamin D and L-arginine as nutraceuticals. L-arginine appears to be a very interesting tool in the clinical management of patients with pre-diabetes. In this review we summarize the current knowledge on the role of L-arginine in prediabetes as a potentially useful preventive strategy against the progression to type 2 diabetes, with a particular focus on the underlying molecular mechanisms and the past and ongoing trials. In this article we also report the interesting data about the perception of the prediabetic condition and its therapeutic management in the clinical practice in Italy. An early identification and a prompt management of people with prediabetes appears to be of paramount importance to prevent the progression to diabetes and avoid its cardiovascular consequences.

Lycium barbarum Polysaccharides Improved Glucose Metabolism in Prediabetic Mice by Regulating Duodenal Contraction

Lycium barbarum polysaccharides (LBPs) have been shown to exert an antiglycemic effect. Emerging evidence suggests that patients with hyperglycemia have a hypercontractility of duodenum, and targeting duodenal contraction of duodenum can be beneficial to glucose metabolism. However, it is unknown whether LBPs can improve glucose metabolism by regulating the hypercontractility of the duodenum. Our aim was to explore the effect of LBPs on duodenal contraction in prediabetic mice and also preliminarily investigate the mechanism. The results showed that LBPs improved glucose homeostasis by decreasing the duodenal amplitude of contraction rather than frequency. Moreover, LBPs ameliorated the gut microbiota composition and the levels of short-chain fatty acids, especially acetic acid, which might bind to the receptor on neurons to regulate the contraction of the duodenum. Acetic acid was hypothesized to play a key role in the above process. Then, acetic acid was determined to exert an antiglycemic effect as expected. In conclusion, LBPs may rely on acetic acid to regulate duodenal contraction to ameliorate glucose metabolism in prediabetic mice, which provides a new therapeutic strategy to treat dysglycemia.

Differential temporal therapies with pharmacologically targeted mitochondrial fission/fusion protect the brain against acute myocardial ischemia-reperfusion injury in prediabetic rats: The crosstalk between mitochondrial apoptosis and inflammation

An imbalance of brain mitochondrial dynamics, increases in brain inflammation and apoptosis, and increasing cognitive dysfunction, have been reported as being associated with prediabetes and myocardial ischemia-reperfusion (IR) injury. Since inhibiting mitochondrial fission with Mdivi-1 or promoting fusion with M1 had cardioprotective effects in myocardial IR injury and obesity, the neuroprotective roles of Mdivi-1 and M1 when administered at different time points of myocardial IR injury in obese prediabetes have never been determined. Ninety-six male Wistar rats were fed with either a normal (ND: n = 8) or a high-fat diet to induce prediabetes (HFD: n = 88) for 12 weeks. At week 13, all rats were subjected to left anterior descending coronary artery ligation for 30 min, followed by reperfusion for 120 min. HFD rats were randomly divided into 10 groups and assigned into either a pre-ischemic group treated with vehicle (HFV), pre-ischemic, during-ischemic, or onset of reperfusion groups treated with either Mdivi-1 (MDV), M1, or combined (COM). Heart function was examined invasively, with the heart being terminated to investigate myocardial infarction. Brains were collected to determine mitochondrial functions, inflammation, apoptosis, and pathological markers. Mdivi-1, M1, and COM treatment at different periods exerted cardioprotection against myocardial IR injury in HFD-fed rats by reducing infarct size and left ventricular dysfunction. All interventions also improved all brain pathologies against myocardial IR injury in prediabetic rats. These findings suggest that differential temporal modulation of mitochondrial dynamics may be appropriate regimens for preventing heart and brain complications after myocardial IR injury in obese prediabetes.

Metformin and exercise effects on postprandial insulin sensitivity and glucose kinetics in pre-diabetic and diabetic adults

The potential interaction between metformin and exercise on glucose-lowering effects remains controversial. We studied the separated and combined effects of metformin and/or exercise on fasting and postprandial insulin sensitivity in individuals with pre-diabetes and type 2 diabetes (T2D). Eight T2D adults (60 ± 4 yr) with overweight/obesity (32 ± 4 kg·m-2) under chronic metformin treatment (9 ± 6 yr; 1281 ± 524 mg·day-1) underwent four trials; 1) taking their habitual metformin treatment (MET), 2) substituting during 96 h their metformin medication by placebo (PLAC), 3) placebo combined with 50 min bout of high-intensity interval exercise (PLAC + EX), and 4) metformin combined with exercise (MET + EX). Plasma glucose kinetics using stable isotopes (6,6-2H2 and [U-13C] glucose), and glucose oxidation by indirect calorimetry, were assessed at rest, during exercise, and in a subsequent oral glucose tolerance test (OGTT). Postprandial glucose and insulin concentrations were analyzed as mean and incremental area under the curve (iAUC), and insulin sensitivity was calculated (i.e., MATSUDAindex and OGISindex). During OGTT, metformin reduced glucose iAUC (i.e., MET and MET + EX lower than PLAC and PLAC + EX, respectively; P = 0.023). MET + EX increased MATSUDAindex above PLAC (4.8 ± 1.4 vs. 3.3 ± 1.0, respectively; P = 0.018) and OGISindex above PLAC (358 ± 52 vs. 306 ± 46 mL·min-1·m-2, respectively; P = 0.006). Metformin decreased the plasma appearance of the ingested glucose (Ra OGTT; MET vs. PLAC, -3.5; 95% CI -0.1 to -6.8 µmol·kg-1·min-1; P = 0.043). Metformin combined with exercise potentiates insulin sensitivity during an OGTT in individuals with pre-diabetes and type 2 diabetes. Metformin's blood glucose-lowering effect seems mediated by decreased oral glucose entering the circulation (gut-liver effect) an effect partially blunted after exercise.NEW & NOTEWORTHY Metformin is the most prescribed oral antidiabetic medicine in the world but its mechanism of action and its interactions with exercise are not fully understood. Our stable isotope tracer data suggested that metformin reduces the rates of oral glucose entering the circulation (gut-liver effect). Exercise, in turn, tended to reduce postprandial insulin blood levels potentiating metformin improvements in insulin sensitivity. Thus, exercise potentiates metformin improvements in glycemic control and should be advised to metformin users.

Metformin for the prevention of diabetes among people with HIV and either impaired fasting glucose or impaired glucose tolerance (prediabetes) in Tanzania: a Phase II randomised placebo-controlled trial

AIMS/HYPOTHESIS

In sub-Saharan Africa (SSA), 5% of adults are living with type 2 diabetes and this is rising sharply, with a greater increase among people with HIV. Evidence on the efficacy of prevention strategies in this cohort is scarce. We conducted a Phase II double-blind placebo-controlled trial that aimed to determine the impact of metformin on blood glucose levels among people with prediabetes (defined as impaired fasting glucose [IFG] and/or impaired glucose tolerance [IGT]) and HIV in SSA.

METHODS

Adults (≥18 years old) who were stable in HIV care and found to have prediabetes (IFG and/or IGT) and who were attending hospitals in Dar es Salaam, Tanzania, were randomised to receive sustained-release metformin, 2000 mg daily, or matching placebo between 4 November 2019 and 21 July 2020. Randomisation used permuted blocks. Allocation was concealed in the trial database and made visible only to the Chief Pharmacist after consent was taken. All participants, research and clinical staff remained blinded to the allocation. Participants were provided with information on diet and lifestyle and had access to various health information following the start of the coronavirus disease 2019 (COVID-19) pandemic. Participants were followed up for 12 months. The primary outcome measure was capillary blood glucose measured 2 h following a 75 g glucose load. Analyses were by intention-to-treat.

RESULTS

In total, 364 participants (182 in each arm) were randomised to the metformin or placebo group. At enrolment, in the metformin and placebo arms, mean fasting glucose was 6.37 mmol/l (95% CI 6.23, 6.50) and 6.26 mmol/l (95% CI 6.15, 6.36), respectively, and mean 2 h glucose levels following a 75 g oral glucose load were 8.39 mmol/l (95% CI 8.22, 8.56) and 8.24 mmol/l (95% CI 8.07, 8.41), respectively. At the final assessment at 12 months, 145/182 (79.7%) individuals randomised to metformin compared with 158/182 (86.8%) randomised to placebo indicated that they had taken >95% of their medicines in the previous 28 days (p=0.068). At this visit, in the metformin and placebo arms, mean fasting glucose levels were 6.17 mmol/l (95% CI 6.03, 6.30) and 6.30 mmol/l (95% CI 6.18, 6.42), respectively, and mean 2 h glucose levels following a 75 g oral glucose load were 7.88 mmol/l (95% CI 7.65, 8.12) and 7.71 mmol/l (95% CI 7.49, 7.94), respectively. Using a linear mixed model controlling for respective baseline values, the mean difference between the metformin and placebo group (metformin-placebo) was -0.08 mmol/l (95% CI -0.37, 0.20) for fasting glucose and 0.20 mmol/l (95% CI -0.17, 0.58) for glucose levels 2 h post a 75 g glucose load. Weight was significantly lower in the metformin arm than in the placebo arm: using the linear mixed model adjusting for baseline values, the mean difference in weight was -1.47 kg (95% CI -2.58, -0.35). In total, 16/182 (8.8%) individuals had a serious adverse event (Grade 3 or Grade 4 in the Division of Acquired Immunodeficiency Syndrome [DAIDS] adverse event grading table) or died in the metformin arm compared with 18/182 (9.9%) in the placebo arm; these events were either unrelated to or unlikely to be related to the study drugs.

CONCLUSIONS/INTERPRETATION

Blood glucose decreased over time in both the metformin and placebo arms during the trial but did not differ significantly between the arms at 12 months of follow up. Metformin therapy was found to be safe for use in individuals with HIV and prediabetes. A larger trial with longer follow up is needed to establish if metformin can be safely used for the prevention of diabetes in people who have HIV.

TRIAL REGISTRATION

The trial is registered on the International Standard Randomised Controlled Trial Number (ISRCTN) registry ( www.isrctn.com/ ), registration number: ISCRTN76157257.

FUNDING

This research was funded by the National Institute for Health Research using UK aid from the UK Government to support global health research.

Effects of treatment with Glucagon-like peptide-1 receptor agonist on prediabetes with overweight/obesity: A systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the effects of Glucagon-like peptide-1 receptor agonist (GLP-1RA) on prediabetes with overweight/obesity.

METHODS

A search of PubMed, Embase, Cochrane Library, and Web of Science databases was performed to identify randomised controlled trials (up to 4 July 2022) which evaluated the effect of GLP-1RA on prediabetes with overweight/obesity.

RESULTS

Eight hundred and nine articles were retrieved (80 from PubMed, 481 from Embase, 137 from Cochrane library, and 111 from Web of Science) and a total of 5 articles were included in this meta-analysis. More individuals in GLP-1RAs group regressed from prediabetes to normoglycemia than individuals in the placebo group (OR = 4.56, 95% CI:3.58, 5.80, P = 0.004); fewer individuals in GLP-1RAs group were diagnosed with diabetes than those in the placebo group (OR = 0.31, 95% CI:0.12,0.81, P = 0.017). Results from five studies showed that GLP-1RAs significantly reduced fasting glucose (mean difference = -0.41 mmol/L, 95% CI: -0.58, -0.25, P < 0.00001), with an acceptable heterogeneity (I2  = 42%).

CONCLUSIONS

The present meta-analysis suggested that GLP-1RA significantly improves glucose metabolism, reduces systolic blood pressure and body weight in prediabetes with overweight/obesity. It could also prevent the development of diabetes and reverse abnormal glucose metabolism.

Design and rationale of the myocardial infarction and new treatment with metformin study (MIMET) - Study protocol for a registry-based randomised clinical trial

AIMS

To investigate if addition of metformin to standard care (life-style advice) reduces the occurrence of cardiovascular events and death after myocardial infarction (MI) in patients with newly detected prediabetes.

METHODS

The Myocardial Infarction and new treatment with Metformin study (MIMET) is a large multicentre registry-based randomised clinical trial (R-RCT) within the SWEDEHEART registry platform expected to include 5160 patients with MI and newly detected prediabetes (identified with fasting blood glucose, HbA1c or 2-h glucose on oral glucose tolerance test) at ∼20 study sites in Sweden. Patients 18-80 years, without known diabetes and naïve to glucose lowering therapy, will be randomised 1:1 to open-label metformin therapy plus standard care or standard care alone.

OUTCOMES

Patients will be followed for 2 years for the primary outcome new cardiovascular event (first of death, non-fatal MI, hospitalisation for heart failure or non-fatal stroke). Secondary endpoints include individual components of the primary endpoint, diabetes diagnosis, initiation of any glucose lowering therapy, cancer, and treatment safety. Events will be collected from national healthcare registries.

CONCLUSIONS

The MIMET study will investigate if metformin is superior to standard care after myocardial infarction in preventing cardiovascular events in patients with prediabetes (Clinicaltrials.gov identifier: NCT05182970; EudraCT No: 2019-001487-30).

Efficacy and safety of HIMABERB® Berberine on glycemic control in patients with prediabetes: double-blind, placebo-controlled, and randomized pilot trial

BACKGROUND

Prediabetes and diabetes involve alterations in glucose homeostasis, including increased fasting blood glucose and impaired glucose tolerance. Berberine has been identified as a potential regulator of glucose homeostasis with implications on the management of type 2 diabetes mellitus (DM). Given a paucity of data on berberine in prediabetes, evaluation of its effect in individuals with prediabetes may prove clinically valuable.

OBJECTIVE

The present pilot study aimed to investigate the effect of daily oral berberine on markers of glycemic control and insulin resistance among individuals with prediabetes.

METHODS

A randomized, double-blinded, placebo-controlled trial was conducted for 12 weeks among 34 individuals with prediabetes as defined by the American Diabetes Association (fasting plasma glucose (FPG) between 5.6 and 6.9 mmol/L, glycosylated hemoglobin (HbA1c) between 5.7% and 6.4%, or 2-hour 75-gram oral glucose tolerance test (2 h-OGTT) between 7.8 and 11.1 mmol/L). HIMABERB® 500 mg was given three times daily to the treatment group, and placebo was administered three times daily to the control group. Glycemic control markers and physical parameters were evaluated for both groups on days 0, 28, 56, and 84. The glycemic control markers assessed included FPG, fasting insulin (FI), 2 h-OGTT, HbA1c, and homeostatic model assessment-insulin resistance (HOMA-IR). The observed outcomes were analyzed using independent t-test statistics to determine the significance of differences over time after treatment initiation and between treatment and control groups.

RESULTS

Significant decreases in all markers of glycemic control were observed in the treatment group at intermediate time points and the endpoint of the study compared to baseline levels and to the control group. For the treatment group, FPG decreased from 6.75 ± 0.23 mmol/L to 5.33 ± 0.28 mmol/L, FI from 9.81 ± 0.36 to 7.88 ± 0.52 mmol/L, 2 h-OGTT from 10.44 ± 0.52 to 8.12 ± 0.40 mmol/L, HbA1c from 6.40% ± 0.20-5.43% ± 0.21%, and HOMA-IR from 3.61 ± 0.31 to 2.41 ± 0.14. The decreases in glycemic control markers compared to the control group were clinically and statistically significant (p<10- 5). No severe adverse effects, kidney or liver toxicity were detected.

CONCLUSION

After 12 weeks, berberine (HIMABERB®) intervention in individuals with prediabetes significantly reduced glycemic control markers, with mean FPG and 2 h-OTGG being reduced to below prediabetic thresholds, supporting the investigation of the use of HIMABERB® for delaying progression to diabetes mellitus.

TRIAL REGISTRATION

http://ctri.nic.in (CTRI/2021/12/038751) (20/12/2021).

Do patients with prediabetes managed with metformin achieve better glycaemic control? A national study using primary care medical records

AIMS

To estimate the effectiveness of metformin on glycaemic parameters among participants with incident prediabetes attending Australian general practices.

METHODS

This retrospective cohort study used electronic health records of regular participants (3+ visits in two consecutive years) attending 383 Australian general practices (MedicineInsight). Participants with 'incident' prediabetes (newly recorded diagnosis between 2012 and 2017) and their glycaemic parameters (haemoglobin A1c [HbA1c] or fasting blood glucose [FBG]) at 6-, 12-, and 18-24 months post diagnosis (unexposed) or post-management with metformin (treatment) were identified from the database. We estimated the average treatment effect (ATE) of metformin management on glycaemic parameters using both linear regression and augmented inverse probability weighting.

RESULTS

Of the 4770 investigated participants with 'incident' prediabetes, 10.2% were managed with metformin. Participants on metformin had higher HbA1c levels at the baseline than those unexposed (mean 45 mmol/mol [6.2%] and 41 mmol/mol [5.9%], respectively), but no differences were observed at 6-12 months (mmol/mol ATE 0.0, 95% CI -0.4; 0.7) or 12-18 months (ATE -0.3, 95% CI -1.2; 0.3). However, participants on metformin had lower mean HbA1c mmol/mol at 18-24 months (ATE -1.1, 95% CI -2.0; 0.1) than those unexposed. Consistent results were observed for FBG (ATE at 6-12 months -0.14 [95% CI -0.25; -0.04], 12-18 months 0.02 [95% CI -0.08; 0.13] and 18-24 months -0.07 [95% CI -0.25; 0.12]).

CONCLUSION

The higher HbA1c and FBG baseline levels among participants with 'incident' prediabetes managed with metformin improved after 6-12 months of starting pharmacological management, and the effect persisted for up to 24 months. Management with metformin could prevent further deterioration of glycaemic levels.

Serum 25(OH)D Concentration, Vitamin D Supplementation, and Risk of Cardiovascular Disease and Mortality in Patients with Type 2 Diabetes or Prediabetes: a Systematic Review and Dose-Response Meta-Analysis

BACKGROUND

Evidence is uncertain about the association between serum 25-hydroxyvitamin D (25(OH)D) concentration and health outcomes in people with type 2 diabetes.

OBJECTIVES

We aimed to assess the association between vitamin D status and all-cause mortality and cardiovascular disease in people with type 2 diabetes.

METHODS

We did a systematic search in PubMed, Scopus, CENTRAL, and Web of Science until May 2022. We selected 1) cohort studies investigating the association between serum 25(OH)D concentration and mortality or cardiovascular disease in people with type 2 diabetes or prediabetes and 2) randomized trials of vitamin D supplementation in these patients. We used random-effects pairwise meta-analyses to calculate summary relative risks (RRs) and 95% confidence intervals (CI).

RESULTS

21 cohort studies and 6 randomized trials were included. Compared with sufficient vitamin D status (≥50 nmol/L), the RR of all-cause mortality was 1.36 (95% CI: 1.23, 1.49; n = 11 studies, GRADE = moderate) for vitamin D insufficiency (25 to <50 nmol/L), and 1.58 (1.33, 1.83; n = 16, GRADE = moderate) for deficiency (<25 nmol/L). Similar findings were observed for cardiovascular mortality and morbidity but not for cancer mortality. The certainty of evidence ranged from very low to moderate. Dose-response meta-analyses indicated nonlinear associations, with the lowest risk at 25(OH)D ∼60 nmol/L for all-cause and cardiovascular mortality. Supplementation with vitamin D did not reduce the risk of all-cause mortality (RR: 0.96, 95% CI: 0.79, 1.16; risk difference per 1000 patients: 3 fewer, 95% CI: 16 fewer, 12 more; n = 6 trials with 7316 participants; GRADE = low) or the risk of cardiovascular mortality and morbidity (very low- to low-certainty evidence).

CONCLUSIONS

Vitamin D deficiency and insufficiency are associated with a higher risk of all-cause and cardiovascular mortality in patients with type 2 diabetes or prediabetes. Vitamin D deficiency should be corrected in patients with type 2 diabetes to reach normal serum 25(OH)D concentrations, preferably 60 nmol/L.

SYSTEMATIC REVIEW REGISTRATION

This systemic review was registered at PROSPERO as CRD42022326429 (=https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=326429).

The effect of metformin treatment on volumes of free-living physical activity and sedentary behaviour: A post-hoc analysis of the PRE-D trial

Perceived physical exertion is increased when exercise is performed on metformin treatment, but the clinical relevance of this is unknown. In this post hoc analysis of a randomized, controlled trial, we investigated whether metformin treatment was associated with lower levels of free-living physical activity.   Ninety individuals with overweight/obesity (BMI>25 m2/kg) and HbA1c-defined prediabetes (39-47 mmol/mol) were randomized to treatment with dapagliflozin (SGLT2-inhibitor; 10 mg once daily, n=30), metformin (850 mg twice daily, n=30) or no treatment (control, n=30) for 13 weeks in a parallel-group, open-label trial. Before (baseline), during (6 weeks) and immediately after (13 weeks) cessation of treatment, a 6-day assessment of physical activity and sedentary behaviour was performed using accelerometer-based physical activity monitors. Intention-to-treat analyses revealed no within-group changes or differences in change between the groups for any measures of physical activity or sedentary behaviour at neither 6 nor 13 weeks. Short-term metformin treatment does not reduce free-living physical activity level in individuals with overweight/obesity and HbA1c-defined prediabetes.

[Efficacy of Sildenafil oral spray for the treatment of erectile dysfunction in patients with type 2 diabetes mellitus and prediabetes]

AIM

To evaluate the results of using Sildenafil in the form of an oral spray (Gent) for the treatment of erectile dysfunction (ED) in men with type 2 diabetes mellitus (DM) and prediabetes.

MATERIAL AND METHODS

A total of 60 patients were divided into two groups of 30 people. The group 1 included patients with prediabetes, while group 2 consisted of patients with type 2 DM. All men had proven ED. The severity of ED was assessed using the International Index of Erectile Function (IIEF-5). To assess the state of penile blood flow, all patients underwent Doppler ultrasound before and after treatment. Patients with prediabetes used Sildenafil in the form of oral spray (Gent) 25 mg (2 doses) 1 time per day for 1 month, patients with type 2 diabetes received 50 mg (4 injections) every other day for 1 month. In addition, most of the subjects took metformin and followed diet therapy.

RESULTS

In patients of both groups, the administration of Sildenafil oral spray led to a decrease in body weight, waist circumference, a decrease in insulin and Hemoglobin A1C level without changing of hypoglycemic therapy in those with type 2 DM. In men with prediabetes, a decrease in fasting insulin levels was found. During treatment, half of the persons with impaired glucose metabolism had an increase in the testosterone level. According to IIEF-5, a decrease in the severity of ED in both groups of patients was seen. In men with prediabetes, the average IIEF-5 score increased from 15.98 to 21.57 points (p<0.05), while in patients with type 2 DM it improved from 12.18 to 18.44 points (p<0.05). Doppler ultrasound indicated a significant increase in the maximum systolic blood flow velocity and arterial resistivity index after treatment with Sildenafil oral spray in patients with both prediabetes and type 2 diabetes.

CONCLUSION

Sildenafil oral spray can be effectively used for the treatment of ED in men with type 2 DM and prediabetes.

Changes in Metabolic Parameters and Body Weight in Patients With Prediabetes Treated With Adjunctive Brexpiprazole for Major Depressive Disorder: Pooled Analysis of Short- and Long-Term Clinical Studies

Objective: Certain atypical antipsychotics, while efficacious as adjunctive treatments in major depressive disorder (MDD), are associated with metabolic adverse effects and weight gain. This analysis determined the effect of adjunctive brexpiprazole on metabolic parameters and body weight in adults with MDD and prediabetes (ie, at risk of developing diabetes) based on pooled data from 3 short-term studies and 1 long-term study.

Methods: The short-term studies were 6-week, randomized, double-blind, placebo-controlled studies of adjunctive oral brexpiprazole 1-3 mg/d in outpatients with MDD (DSM-IV-TR criteria) and inadequate response to antidepressant treatment, conducted between June 2011 and May 2016. The long-term study was a 26- to 52-week, open-label extension study conducted between October 2011 and May 2017. Prediabetes was defined based on fasting serum glucose and glycated hemoglobin (HbA1c) levels. Shifts in diabetes status and shifts/changes in fasting metabolic parameters and body weight were determined.

Results: Most patients receiving adjunctive brexpiprazole maintained their baseline diabetes status in the short term (568/751; 75.6%) and long term (1,919/2,746; 69.9%). The incidence of categorical shifts in fasting metabolic parameters generally did not differ between treatment groups or between prediabetes and non-diabetes subgroups. Mean changes from baseline in metabolic parameters were small in the short term (all < 5 mg/dL) and long term (all < 6 mg/dL, except < 20 mg/dL for triglycerides). Moderate weight gain was observed in the short term (1.5 kg) and long term (3.4-4.1 kg).

Conclusions: Adjunctive brexpiprazole had a limited impact on the metabolic profile of patients with MDD, regardless of diabetes status (prediabetes/non-diabetes).

Trial Registration: Data used in this post hoc analysis came from studies with ClinicalTrials.gov identifiers NCT01360645, NCT01360632, NCT02196506, and NCT01360866.

Identification of Genetic Variation Influencing Metformin Response in a Multiancestry Genome-Wide Association Study in the Diabetes Prevention Program (DPP)

Genome-wide significant loci for metformin response in type 2 diabetes reported elsewhere have not been replicated in the Diabetes Prevention Program (DPP). To assess pharmacogenetic interactions in prediabetes, we conducted a genome-wide association study (GWAS) in the DPP. Cox proportional hazards models tested associations with diabetes incidence in the metformin (MET; n = 876) and placebo (PBO; n = 887) arms. Multiple linear regression assessed association with 1-year change in metformin-related quantitative traits, adjusted for baseline trait, age, sex, and 10 ancestry principal components. We tested for gene-by-treatment interaction. No significant associations emerged for diabetes incidence. We identified four genome-wide significant variants after correcting for correlated traits (P < 9 × 10-9). In the MET arm, rs144322333 near ENOSF1 (minor allele frequency [MAF]AFR = 0.07; MAFEUR = 0.002) was associated with an increase in percentage of glycated hemoglobin (per minor allele, β = 0.39 [95% CI 0.28, 0.50]; P = 2.8 × 10-12). rs145591055 near OMSR (MAF = 0.10 in American Indians) was associated with weight loss (kilograms) (per G allele, β = -7.55 [95% CI -9.88, -5.22]; P = 3.2 × 10-10) in the MET arm. Neither variant was significant in PBO; gene-by-treatment interaction was significant for both variants [P(G×T) < 1.0 × 10-4]. Replication in individuals with diabetes did not yield significant findings. A GWAS for metformin response in prediabetes revealed novel ethnic-specific associations that require further investigation but may have implications for tailored therapy.

The effect of phytochemicals in prediabetic patients: A systematic review of randomized controlled trials

This study aimed to perform a systematic review to evaluate the effect of phytochemical consumption on the cardiometabolic parameters of prediabetic patients. A comprehensive search was conducted in PubMed, Scopus and ISI Web of Science, and Google Scholar up to June 2022 to find randomized controlled trials investigating the effects of phytochemicals alone or in combination with other nutraceuticals on prediabetic patients. Twenty-three studies with 31 treatment arms comprising 2177 individuals were included in this study. Totally, in 21 arms, phytochemicals had positive effects on at least one measured cardiometabolic factor. In 13 out of 25 arms, fasting blood glucose (FBG) and in 10 out of 22 arms, hemoglobin A1c (HbA1c) significantly decreased compared with the control group. Furthermore, phytochemicals had beneficial effects on 2-h postprandial and postprandial glucose, serum insulin, insulin sensitivity, and insulin resistance as well as inflammatory factors including high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6). Triglyceride (TG) was the abundant improved factor in the lipid profile. However, no sufficient evidence for notable positive effects of phytochemicals on blood pressure and anthropometry indices was observed. Phytochemical supplementation may have beneficial impacts on prediabetic patients by ameliorating glycemic status.

Safety and effectiveness of metformin plus lifestyle intervention compared with lifestyle intervention alone in preventing progression to diabetes in a Chinese population with impaired glucose regulation: a multicentre, open-label, randomised controlled trial

BACKGROUND

Impaired glucose regulation (defined as either impaired glucose tolerance or impaired fasting glucose) is an important risk factor for the development of diabetes. We aimed to evaluate the safety and effectiveness of metformin plus lifestyle intervention compared with lifestyle intervention alone in preventing diabetes in Chinese participants with impaired glucose regulation.

METHODS

We did a multicentre, open-label, randomised controlled trial at 43 endocrinology departments in general hospitals across China. Eligible participants were individuals with impaired glucose regulation (ie, impaired glucose tolerance or impaired fasting glucose, or both), men or women aged 18-70 years with a BMI of 21-32 kg/m2. Eligible participants were randomly assigned (1:1) via a computer-generated randomisation to receive either standard lifestyle intervention alone or metformin (850 mg orally once per day for the first 2 weeks and titrated to 1700 mg orally per day [850 mg twice per day]) plus lifestyle intervention. Block randomisation was used with a block size of four, stratified by glucose status (impaired fasting glucose or impaired glucose tolerance), hypertension, and use of any anti-hypertensive medication. Lifestyle intervention advice was given by investigators at all participating sites. The primary endpoint was the incidence of newly diagnosed diabetes at the end of the 2-year follow-up. Analysis was done using the full analysis set and per-protocol set. This study is registered with ClinicalTrials.gov, number NCT03441750, and is completed.

FINDINGS

Between April, 2017, and June, 2019, 3881 individuals were assessed for eligibility, of which 1678 (43·2%) participants were randomly assigned to either the metformin plus lifestyle intervention group (n=831) or the lifestyle intervention alone group (n=847) and received the allocated intervention at least once. During a median follow-up of 2·03 years, the incidence rate of diabetes was 17·27 (95% CI 15·19-19·56) per 100 person-years in the metformin plus lifestyle intervention group and 19·83 (17·67-22·18) per 100 person-years in the lifestyle intervention alone group. The metformin plus lifestyle intervention group showed a 17% lower risk of developing diabetes than the lifestyle intervention alone group (HR 0·83 [95% CI 0·70-0·99]; log-rank p=0·043). A higher proportion of participants in the metformin plus lifestyle intervention group reported adverse events than in the lifestyle intervention alone group, primarily due to more gastrointestinal adverse events. The percentage of participants reporting a serious adverse event was similar in both groups.

INTERPRETATION

Metformin plus lifestyle intervention further reduced the risk of developing diabetes than lifestyle intervention alone in Chinese people with impaired glucose regulation, showing additional benefits of combined intervention in preventing progression to diabetes without new safety concerns.

FUNDING

Merck Serono China, an affiliate of Merck KGaA, Darmstadt, Germany.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Effect of the glucagon-like peptide-1 receptor agonist liraglutide, compared to caloric restriction, on appetite, dietary intake, body fat distribution and cardiometabolic biomarkers: A randomized trial in adults with obesity and prediabetes

AIMS

To investigate the hypothesis that weight loss with the glucagon-like peptide-1 receptor agonist (GLP-1RA) liraglutide alone would lead to a greater reduction in the proportion of fat to lean tissue mass when compared to caloric restriction (CR) alone, as well as when compared to treatment with sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, that also enhances GLP-1 activity - to determine the independent effects of each treatment.

METHODS

A total of 88 adults with obesity and prediabetes were randomized to 14 weeks of intervention with CR (-390 kcal/d), liraglutide (1.8 mg/d), or the dipeptidyl peptidase-4 inhibitor sitagliptin (100 mg/d) as a weight-neutral comparator. Changes between groups in appetite and hunger ratings measured via visual analogue scales, dietary intakes, body weight, body composition via dual energy x-ray absorptiometry, and resting energy expenditure via indirect calorimetry were assessed using the Kruskal-Wallis test or Pearson's chi-squared test.

RESULTS

Weight loss ≥5% of baseline body weight occurred in 44% of participants in the CR group, 22% of the liraglutide group and 5% of the sitagliptin group (p = 0.02). The ratio of fat to lean mass decreased by 6.5% in the CR group, 2.2% in the liraglutide group, and 0% in the sitagliptin group (p = 0.02). Visceral fat reduced by 9.5% in the CR group, 4.8% in the liraglutide group, and 0% in the sitagliptin group (p = 0.04). A spontaneous reduction in dietary simple carbohydrates in the CR group was associated with improved homeostatic model assessment of insulin resistance score (HOMA-IR).

CONCLUSIONS

Although both liraglutide and CR are valuable strategies for cardiometabolic risk reduction, CR was associated with greater weight loss and more favourable improvements in body composition than treatment with liraglutide alone. Differences in the response to each of these interventions enables patients to be stratified to the most optimal intervention for their personal risk factors.

Effects of turmeric (Curcuma longa) supplementation on glucose metabolism in diabetes mellitus and metabolic syndrome: An umbrella review and updated meta-analysis

AIMS

This study aims to comprehensively review the existing evidence and conduct analysis of updated randomized controlled trials (RCTs) of turmeric (Curcuma longa, CL) and its related bioactive compounds on glycemic and metabolic parameters in patients with type 2 diabetes (T2DM), prediabetes, and metabolic syndrome (MetS) together with a sub-group analysis of different CL preparation forms.

METHODS

An umbrella review (UR) and updated systematic reviews and meta-analyses (SRMAs) were conducted to evaluate the effects of CL compared with a placebo/standard treatment in adult T2DM, prediabetes, and MetS. The MEDLINE, Embase, The Cochrane Central Register of Control Trials, and Scopus databases were searched from inception to September 2022. The primary efficacy outcomes were hemoglobin A1C (HbA1C) and fasting blood glucose (FBG). The corrected covered area (CCA) was used to assess overlap. Mean differences were pooled across individual RCTs using a random-effects model. Subgroup and sensitivity analyses were performed for various CL preparation forms.

RESULTS

Fourteen SRMAs of 61 individual RCTs were included in the UR. The updated SRMA included 28 studies. The CCA was 11.54%, indicating high overlap across SRMAs. The updated SRMA revealed significant reduction in FBG and HbA1C with CL supplementation, obtaining a mean difference (95% confidence interval [CI]) of -8.129 (-12.175, -4.084) mg/dL and -0.134 (-0.304, -0.037) %, respectively. FBG and HbA1C levels decreased with all CL preparation forms as did other metabolic parameters levels. The results of the sensitivity and subgroup analyses were consistent with those of the main analysis.

CONCLUSION

CL supplementation can significantly reduce FBG and HbA1C levels and other metabolic parameters in T2DM and mitigate related conditions, including prediabetes and MetS.

TRIAL REGISTRATION

PROSPERO (CRD42016042131).

Astaxanthin, a natural antioxidant, lowers cholesterol and markers of cardiovascular risk in individuals with prediabetes and dyslipidaemia

AIM

To determine the effects of astaxanthin treatment on lipids, cardiovascular disease (CVD) markers, glucose tolerance, insulin action and inflammation in individuals with prediabetes and dyslipidaemia.

MATERIALS AND METHODS

Adult participants with dyslipidaemia and prediabetes (n = 34) underwent baseline blood draw, an oral glucose tolerance test and a one-step hyperinsulinaemic-euglycaemic clamp. They were then randomized (n = 22 treated, 12 placebo) to receive astaxanthin 12 mg daily or placebo for 24 weeks. Baseline studies were repeated after 12 and 24 weeks of therapy.

RESULTS

After 24 weeks, astaxanthin treatment significantly decreased low-density lipoprotein (-0.33 ± 0.11 mM) and total cholesterol (-0.30 ± 0.14 mM) (both P < .05). Astaxanthin also reduced levels of the CVD risk markers fibrinogen (-473 ± 210 ng/mL), L-selectin (-0.08 ± 0.03 ng/mL) and fetuin-A (-10.3 ± 3.6 ng/mL) (all P < .05). While the effects of astaxanthin treatment did not reach statistical significance, there were trends toward improvements in the primary outcome measure, insulin-stimulated, whole-body glucose disposal (+0.52 ± 0.37 mg/m2 /min, P = .078), as well as fasting [insulin] (-5.6 ± 8.4 pM, P = .097) and HOMA2-IR (-0.31 ± 0.16, P = .060), suggesting improved insulin action. No consistent significant differences from baseline were observed for any of these outcomes in the placebo group. Astaxanthin was safe and well tolerated with no clinically significant adverse events.

CONCLUSIONS

Although the primary endpoint did not meet the prespecified significance level, these data suggest that astaxanthin is a safe over-the-counter supplement that improves lipid profiles and markers of CVD risk in individuals with prediabetes and dyslipidaemia.

The Influence of baseline glycemic status on the effects of intensive blood pressure lowering: Results from the STEP randomized trial

BACKGROUND

Intensive systolic blood pressure (SBP) lowering showed cardiovascular benefits in the Strategy of Blood Pressure Intervention in the Elderly Hypertensive Patients (STEP) trial. We investigated whether baseline glycemic status influences the effects of intensive SBP lowering on cardiovascular outcomes.

METHODS

In this post hoc analysis of the STEP trial, participants were randomly assigned to receive intensive (110 to <130 mmHg) or standard SBP treatment (130 to <150 mmHg) and categorized by baseline glycemic status into three subgroups: normoglycemia, prediabetes, and diabetes. The primary outcome was a composite of stroke, acute coronary syndrome, acute decompensated heart failure, coronary revascularization, atrial fibrillation, or death from cardiovascular causes. A competing risk proportional hazards regression model was used in the analysis.

RESULTS

Of the 8,318 participants, 3,275, 2,769, and 2,274 had normoglycemia, prediabetes, and diabetes, respectively. Over a median follow-up of 3.33 years, intensive SBP lowering significantly reduced the risk of the primary outcome (adjusted hazard ratio 0.73, 95% confidence interval [CI] 0.59-0.91). The adjusted hazard ratios for the primary outcome in the normoglycemia, prediabetes, and diabetes subgroups were 0.72 (95% CI 0.49-1.04), 0.69 (95% CI 0.46-1.02), and 0.80 (95% CI 0.56-1.15), respectively. The intensive SBP lowering strategy resulted in similar effects among participants in the three subgroups (all interaction P >0.05). The sensitivity analyses showed consistent results with the main analysis.

CONCLUSION

The effects of intensive SBP lowering on cardiovascular outcomes were consistent among participants with normoglycemia, prediabetes, and diabetes.

Effect of prediabetes on tuberculosis treatment outcomes: A study from South India

BACKGROUND AND AIMS

The aim was to assess the effect of prediabetes on tuberculosis(TB) treatment outcomes.

METHODS

This is a prospective observational cohort study of 569 eligible new smear positive cases screened for DM between 2014 and 2018 in TB units in North Chennai, South India. Based on study criteria, a total of 187 subjects were included and categorised into two groups: TB with normoglycaemia (groupI) (HbA1c<5.7%) and TB with prediabetes (group II) (HbA1c = 5.7-6.4%) and followed them at 3rd and 6th month and treatment outcomes were assessed at the end of the TB treatment.

RESULTS

Total cure rate was 72.7% with no significant difference between the groups. Higher proportion of deaths occurred in group II (6.3%) compared to group I (1.3%) (p = 0.09). At the end of intensive phase of directly observed therapy (DOTS) treatment, about 23.8% were observed to have positive sputum smear in group II compared to 8.6% in group I(p = 0.019). The estimated relative risk to remain as sputum smear positive among people with prediabetes at the end of intensive phase was 3.0(95% CI: 1.2-7.6). There was a significant association found with HbA1c at enrollment and unfavourable TB treatment outcomes (β = 1.38, [odds ratio (95% CI) 3.98(1.65-9.64); p = 0.007].

CONCLUSION

Death rate was high and there was a delay in sputum conversion among TB patients with prediabetes at the end of the intensive phase of TB treatment. HbA1c at the time of diagnosis of prediabetes was significantly associated with unfavourable TB treatment outcomes.

New-onset diabetes with sodium-glucose cotransporter-2 inhibitors in prediabetes: An updated meta-analysis and possible mechanisms

BACKGROUND AND AIMS

A recent systematic review and meta-analysis studied the effect of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on new-onset diabetes (NOD) in adults with prediabetes having chronic kidney disease and heart failure. In light of other large randomized controlled trials (RCTs) of SGLT2i published after this meta-analysis that also reported the NOD outcome in adults with prediabetes, it is of interest to update the NOD outcome with SGLT2i.

METHODS

A systemic search in the PubMed and Embase electronic database was made until March 31, 2023, using specific MeSH keywords following PRISMA protocol. Subsequently, we conducted a meta-analysis using the random effects model while applying the inverse variance-weighted averages of pooled logarithmic hazard ratio (HR). Heterogeneity was measured using Higgins I² and Cochrane Q statistics and publication bias was evaluated by applying funnel plots. A sensitivity exclusion analysis was additionally made.

RESULTS

This meta-analysis of five RCTs (N = 6752) found a significant reduction in NOD (HR 0.81; 95% CI, 0.69-0.94; P = 0.005) with SGLT2i in adults with prediabetes without any heterogeneity (I² = 0%).

CONCLUSIONS

SGLT2i has the potential to reduce NOD in adults with prediabetes. Since no effect on HbA1c reduction was seen in adults with prediabetes in all five RCTs included in this meta-analysis, it is conceivable that reduction in NOD is not related to the masking of blood glucose exerted by SGLT2i. However, only an adequately powered trial of SGLT2i in people with prediabetes with a sufficient wash-out period will confirm these findings.

Vitamin D supplementation alleviates insulin resistance in prediabetic rats by modifying IRS-1 and PPARγ/NF-κB expressions

Background

Prediabetes is a condition of intermediate hyperglycemia that may progress to type 2 diabetes. Vitamin D deficiency has been frequently linked to insulin resistance and diabetes. The study aimed to investigate the role of D supplementation and its possible mechanism of action on insulin resistance in prediabetic rats.

Method

The study was conducted on 24 male Wistar rats that were randomly divided into 6 rats as healthy controls and 18 prediabetic rats. Prediabetic rats were induced with a high-fat and high-glucose diet (HFD-G) combined with a low dose of streptozotocin. Rats with the prediabetic condition were then randomized into three groups of 12-week treatment: one group that received no treatment, one that received vitamin D3 at 100 IU/kg BW, and one group that received vitamin D3 at 1000 IU/kg BW. The high-fat and high-glucose diets were continuously given throughout the twelve weeks of treatment. At the end of the supplementation period, glucose control parameters, inflammatory markers, and the expressions of IRS1, PPARγ, NF-κB, and IRS1 were measured.

Results

Vitamin D3 dose-dependently improves glucose control parameters, as shown by the reduction of fasting blood glucose (FBG), oral glucose tolerance test (OGTT), glycated albumin, insulin levels, and markers of insulin resistance (HOMA-IR). Upon histological analysis, vitamin D supplementation resulted in a reduction of the islet of Langerhans degeneration. Vitamin D also enhanced the ratio of IL-6/IL-10, reduced IRS1 phosphorylation at Ser307, increased expression of PPAR gamma, and reduced phosphorylation of NF-KB p65 at Ser536.

Conclusion

Vitamin D supplementation reduces insulin resistance in prediabetic rats. The reduction might be due to the effects of vitamin D on IRS, PPARγ, and NF-κB expression.

In prediabetes, oral vitamin D reduces progression to new-onset diabetes

SOURCE CITATION

Pittas AG, Kawahara T, Jorde R, et al. Vitamin D and risk for type 2 diabetes in people with prediabetes: a systematic review and meta-analysis of individual participant data from 3 randomized clinical trials. Ann Intern Med. 2023;176:355-363. 36745886.

Effects of Intensive Systolic Blood Pressure Lowering on End-Stage Kidney Disease and Kidney Function Decline in Adults With Type 2 Diabetes Mellitus and Cardiovascular Risk Factors: A Post Hoc Analysis of ACCORD-BP and SPRINT

OBJECTIVE

To determine the effects of intensive systolic blood pressure (SBP) lowering on the risk of major adverse kidney outcomes in people with type 2 diabetes mellitus (T2DM) and/or prediabetes and cardiovascular risk factors.

RESEARCH DESIGN AND METHODS

This post hoc ACCORD-BP subgroup analysis included participants in the standard glucose-lowering arm with cardiovascular risk factors required for SPRINT eligibility. Cox proportional hazards regression models compared the hazard for the composite of dialysis, kidney transplant, sustained estimated glomerular filtration rate (eGFR) <15 mL/min/1.73 m2, serum creatinine >3.3 mg/dL, or a sustained eGFR decline ≥57% between the intensive (<120 mmHg) and standard (<140 mmHg) SBP-lowering arms.

RESULTS

The study cohort included 1,966 SPRINT-eligible ACCORD-BP participants (40% women) with a mean age of 63 years. The mean SBP achieved after randomization was 120 ± 14 and 134 ± 15 mmHg in the intensive and standard arms, respectively. The kidney composite outcome occurred at a rate of 9.5 and 7.2 events per 1,000 person-years in the intensive and standard BP arms (hazard ratio [HR] 1.35 [95% CI 0.85-2.14]; P = 0.20). Intensive SBP lowering did not affect the risk of moderately (HR 0.96 [95% CI 0.76-1.20]) or severely (HR 0.92 [95% CI 0.66-1.28]) increased albuminuria. Including SPRINT participants with prediabetes in the cohort did not change the overall results.

CONCLUSIONS

This post hoc subgroup analysis suggests that intensive SBP lowering does not increase the risk of major adverse kidney events in individuals with T2DM and cardiovascular risk factors.