Hypoglycemia and Cardiovascular Outcomes in the CARMELINA and CAROLINA Trials of Linagliptin: A Secondary Analysis of Randomized Clinical Trials

Use of adjunctive glycaemic agents with vascular protective properties in individuals with type 1 diabetes: Potential benefits and risks

Glycaemic therapy in type 1 diabetes (T1D) is focused on insulin, with the majority of studies investigating different insulin preparations, delivery devices and dosing accuracy methods. While insulin deficiency is the key mechanism for hyperglycaemia in T1D, individuals with this condition can also develop insulin resistance (IR), making optimisation of glycaemia more challenging. Importantly, IR in T1D increases the risk of both microvascular and macrovascular complications; yet, it is rarely targeted in routine clinical care. In this narrative review, we briefly discuss the mechanistic pathways for diabetes complications in individuals with T1D, emphasising the adverse role of IR. We subsequently cover the use of adjunctive glycaemic therapies for improving the metabolic profile in T1D, focusing on therapies that have possible or definite cardiovascular or renal protective properties in individuals with type 2 diabetes. These include metformin and agents in the thiazolidinedione, Sodium-Glucose Cotransporter-2 inhibitor (SGLT2i) and Glucagon-Like Peptide-1 Receptor Agonists (GLP-1RA) groups. In addition to reviewing the role of these agents in improving metabolic parameters, we address their potential vascular and renal protective effects in individuals with T1D. We suggest a pragmatic approach for using these agents in T1D, based on current knowledge of their benefits and risks, while also highlighting gaps in knowledge and areas that require further research. It is hoped that the review raises awareness of the role of adjunctive therapies in T1D and offers healthcare professionals simple guidance on using such agents for the management of high-risk individuals with T1D.

Modulation of FOXO3a Nuclear Localization by Linagliptin (BI-1356) reveals a new therapeutic target in chronic ulcerative colitis

Globally, the incidence and prevalence rates of ulcerative colitis (UC) show a rising pattern. The limited efficacy and significant adverse effects associated with current treatment options underscore the need for novel therapeutic approaches. It has been found that linagliptin, a dipeptidyl peptidase-4 inhibitor, activates AMPK in different disease conditions. The main objective of the present work was to elucidate the potential implications of the AMPK/FOXO3a mediated by linagliptin in rats with chronic colitis. The findings of the current report revealed the first robust in-vivo evidence advocating the coloprotective effect of linagliptin against dextran sodium sulfate-induced chronic UC in rats. It has demonstrated potential beyond its antidiabetic effects by modulating FOXO3a localization. By shifting FOXO3a from the cytosol to the nucleus, linagliptin enhanced the transcription of genes involved in attenuation of pro-inflammatory events and restoration of redox homeostasis. Nuclear FOXO3a also impacted NFκB activity, reducing inflammation. This conclusion was fundamentally supported by the documented improvements in histopathological changes evidenced by reduced inflammation, edema, crypt atrophy, and submucosal fibrosis. Moreover, decreased colon weight/length ratio, as well as reduced scores of disease activity and macroscopic damage indices, were observed. Furthermore, it corrected body weight loss during the time frame of the experiment. These findings underscore the anti-inflammatory potential of therapies that promote the nuclear localization of FOXO3a in inflammatory conditions. Linagliptin's ability to modulate FOXO3a localization might be particularly useful for diabetic patients suffering from inflammatory bowel diseases. However, further molecular investigations are required to validate the findings and to assess the clinical application of this approach as a valid tool for alleviating UC.

Linagliptin exerts a sex-specific effect on cardiac function, collateralization, and metabolism in a swine model of cardiometabolic disease

OBJECTIVE

There are striking sex disparities among cardiometabolic disorders; however, the understanding of its underlying disease pathology remains uncertain, creating insufficient preventative and therapeutic approaches. Our study investigates the sex-specific response to the dipeptidyl peptidase-4 inhibitor, linagliptin in a clinically meaningful model of metabolic syndrome and chronic myocardial ischemia.

METHODS

Yorkshire swine were fed a high-fat diet for 5 weeks to induce metabolic syndrome and subsequently underwent placement of an ameroid constrictor to the left circumflex coronary artery, inducing chronic myocardial ischemia. Swine received no drug (n = 8; 4 females, 4 males) or 2.5 mg linagliptin daily (n = 8; 3 males, 5 females). Five weeks later, the swine underwent hemodynamic measurements, microsphere injections to determine perfusion, and terminal harvest for left ventricular sectioning and molecular and proteomic analysis.

RESULTS

Linagliptin-treated female swine demonstrated improved cardiac function compared with treated males and controls, including cardiac output, stroke work, and left ventricular end-diastolic volume (all P < .05). There was an increase in arteriolar and capillary density in treated female swine compared with control (P = .002, P = .031, respectively), with associated sex-specific changes in angiogenic proteins. Treated male swine had reduced glycogen stores by periodic acid-Schiff staining compared with control (P = .017). In contrast, female-treated swine had a nonsignificant reduction in glycogen stores and an upregulation of proteins associated with overall mitochondrial function and glycolysis.

CONCLUSIONS

Linagliptin treatment resulted in a preferential improvement in left ventricular function, angiogenesis, and "metabolic flexibility" in female swine compared with male swine and controls in the setting of metabolic syndrome and coronary artery disease.

Photoplethysmography-Derived Arterial Stiffness Index Delivered Greater Cardiovascular Prevention Value to Non-Elderly: A Retrospective Cohort Study Based on UK Biobank

Photoplethysmography-derived arterial stiffness index (ASI) has been proven to be associated with various cardiovascular diseases. The present study aims to determine whether the predictive value of ASI varies between elderly and non-elderly and whether ASI improves the discrimination and reclassification ability of the updated Systematic Coronary Risk Evaluation (SCORE2) in different age groups. This retrospective study included UK Biobank participants with ASI recordings. Multivariable Cox proportional hazard models were used to estimate the associations between ASI and major adverse cardiovascular events (MACE) in different age groups. The difference in C-statistic, integrated discrimination improvement (IDI), and continuous net reclassification improvement (NRI) were calculated to test the predictive performance of ASI beyond SCORE2 in the elderly and non-elderly. A total of 127 045 participants were included in the primary analysis. During a median of 11.7 years, 2606 (10.7%) and 4408 (4.3%) MACE were identified in the elderly and non-elderly, respectively. The non-elderly exhibited a greater extent of increased risk for MACE with higher ASI (HR, 1.314 [1.280-1.350] vs. HR, 1.066 [1.026-1.107]). Furthermore, the IDI and continuous NRI of ASI beyond SCORE2 for MACE were more than two times higher for non-elderly individuals than their elderly counterparts (IDI, 0.0481% [0.0182%-0.0953%] vs. IDI, 0.0010% [-0.0052% to 0.0295%]; NRI, 8.76% [6.83% to 10.60%] vs. NRI, 3.27% [-3.92% to 5.97%]). Our findings suggested that ASI should primarily be utilized for primary cardiovascular prevention in individuals below 65.

Anti-Inflammatory and Survival Benefits of Dipeptidyl Peptidase 4 Inhibitors Among Patients with Gout, T2DM Patients and Chronic Kidney Disease

Gout and type 2 diabetes mellitus (T2DM) often coexist and are associated with chronic kidney disease (CKD) and increased mortality. Dipeptidyl peptidase-4 (DPP-4) inhibitors, commonly used in T2DM, may offer additional benefits, such as reducing inflammation and uric acid levels. This study aimed to assess the impact of DPP-4 inhibitors on gout flare frequency, serum uric acid (sUA) levels, and survival in patients with gout, T2DM, and CKD.A cross-sectional, retrospective, longitudinal study was conducted over 6 years between 2016 - 2022, including patients with gout and T2DM from the largest healthcare provider in Israel. Patients were divided into treatment and control groups based on DPP4-inhibitor status treatment. The primary outcome was the number of gout arthritis attacks over 1 year, reflected by the number of emergency room visits. Secondary outcomes included mean serum high-sensitive C-reactive protein (hs-CRP) levels and survival rates over the study period.DPP-4 inhibitor treatment significantly reduced sUA levels (5.2±1.3 mg/dL vs. 5.9±2.2 mg/dL, p=0.05) and hs-CRP levels (0.50±0.19 mg/dL, p<0.001). Kaplan-Meier survival analysis suggested a trend towards improved survival in the DPP-4 inhibitor group (HR=0.834, 95% CI: 0.6-1.04, p=0.05), particularly among patients with chronic kidney disease (CKD), although without statistical significance. The emergency room visits due to gout attacks were fewer in the DPP-4 inhibitor group, although this difference did not achieve statistical significance.DPP-4 inhibitors may offer benefits beyond glycemic control in T2DM and gout, including reduced sUA and hs-CRP levels and improved survival in CKD patients. Larger, randomized trials are warranted to explore these potential benefits.

Monitoring individualized glucose levels predicts risk for bradycardia in type 2 diabetes patients with chronic kidney disease: a pilot study

Patients with diabetes mellitus (DM) and chronic kidney disease (CKD) exhibit an elevated risk for cardiac arrhythmias, such as bradycardia, which may potentially lead to sudden cardiac death (SCD). While hypoglycemia, defined as a critical drop in glucose levels below the normal range, has long been associated with adverse cardiovascular events, recent studies have highlighted the need for a comprehensive reevaluation of its direct impact on cardiovascular outcomes, particularly in high-risk populations such as those with DM and CKD. In this study, we investigated the association between glucose levels and bradycardia by simultaneously monitoring interstitial glucose (IG) and ECG for 7 days in insulin-treated patients with DM and CKD. We identified bradycardia episodes in 19 of 85 patients (22%) and associated these episodes with personalized low, medium, and high relative glucose levels. Our analysis revealed a significant increase in bradycardia frequency during periods of lowest relative glucose, particularly between 06:00-09:00 and 12:00-15:00. Furthermore, leveraging a Random Forests classifier, we achieved a promising area under the curve (AUC) of 0.94 for predicting bradyarrhythmias using glucose levels and heart rate variability features. Contrary to previous findings, only 4% of bradycardia episodes in our study population occurred at glucose levels of 70 mg/dL or lower, with 28% observed at levels exceeding 180 mg/dL. Our findings not only highlight the strong correlation between relative glucose levels, heart rate parameters, and bradycardia onset but also emphasize the need for a more personalized definition of hypoglycemia to understand its relationship with bradyarrhythmias in high-risk DM and CKD patient populations.

Advances in small-molecule insulin secretagogues for diabetes treatment

Diabetes, a metabolic disease caused by abnormally high levels of blood glucose, has a high prevalence rate worldwide and causes a series of complications, including coronary heart disease, stroke, peripheral vascular disease, end-stage renal disease, and retinopathy. Small-molecule compounds have been developed as drugs for the treatment of diabetes because of their oral advantages. Insulin secretagogues are a class of small-molecule drugs used to treat diabetes, and include sulfonylureas, non-sulfonylureas, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase 4 inhibitors, and other novel small-molecule insulin secretagogues. However, many small-molecule compounds cause different side effects, posing huge challenges to drug monotherapy and drug selection. Therefore, the use of different small-molecule drugs must be improved. This article reviews the mechanism, advantages, limitations, and potential risks of small-molecule insulin secretagogues to provide future research directions on small-molecule drugs for the treatment of diabetes.

Tight versus liberal blood-glucose control in the intensive care unit: special considerations for patients with diabetes

Stress hyperglycaemia, hypoglycaemia, and diabetes are common in critically ill patients and related to clinical endpoints. To avoid complications related to hypoglycaemia and hyperglycaemia, it is recommended to start insulin therapy for the majority of critically ill patients with persistent blood glucose concentrations higher than 10·0 mmol/L (>180 mg/dL), targeting a range of 7·8-10·0 mmol/L (140-180 mg/dL). However, management and evidence-based targets for blood glucose control are under debate, particularly for patients with diabetes. Recent randomised controlled clinical trials now challenge current recommendations. In this Personal View, we aim to highlight these developments and the important differences between critically ill patients with and without diabetes, taking into account the considerable heterogeneity in this patient group. We critically discuss evidence from prospective randomised controlled trials and observational studies on the safety and efficacy of glycaemic control, specifically in the context of patients with diabetes in intensive care units.