Cardiovascular efficacy and safety of dipeptidyl peptidase-4 inhibitors: A meta-analysis of cardiovascular outcome trials

BACKGROUND Dipeptidyl peptidase-4(DPP-4) inhibitors are a generally safe and well tolerated antidiabetic drug class with proven efficacy in type 2 diabetes mellitus(T2 DM). Recently, a series of large, randomized controlled trials(RCTs) addressing cardiovascular outcomes with DPP-4 inhibitors have been published.AIM To pool data from the aforementioned trials concerning the impact of DPP-4 inhibitors on surrogate cardiovascular efficacy outcomes and on major cardiac arrhythmias.METHODS We searched PubMed and grey literature sources for all published RCTs assessing cardiovascular outcomes with DPP-4 inhibitors compared to placebo until October 2020. We extracted data concerning the following "hard" efficacy outcomes: fatal and non-fatal myocardial infarction, fatal and non-fatal stroke, hospitalization for heart failure, hospitalization for unstable angina, hospitalization for coronary revascularization and cardiovascular death. We also extracted data regarding the risk for major cardiac arrhythmias, such as atrial fibrillation, atrial flutter, ventricular fibrillation and ventricular tachycardia.RESULTS We pooled data from 6 trials in a total of 52520 patients with T2 DM assigned either to DPP-4 inhibitor or placebo. DPP-4 inhibitors compared to placebo led to a non-significant increase in the risk for fatal and non-fatal myocardial infarction [risk ratio(RR) = 1.02, 95%CI: 0.94-1.11, I2 = 0%], hospitalization for heart failure(RR = 1.09, 95%CI: 0.92-1.29, I2 = 65%) and cardiovascular death(RR = 1.02, 95%CI: 0.93-1.11, I2 = 0%). DPP-4 inhibitors resulted in a non-significant decrease in the risk for fatal and non-fatal stroke(RR = 0.96, 95%CI: 0.85-1.08, I2 = 0%) and coronary revascularization(RR = 0.99, 95%CI: 0.90-1.09, I2 = 0%), Finally, DPP-4 inhibitors demonstrated a neutral effect on the risk for hospitalization due to unstable angina(RR = 1.00, 95%CI: 0.85-1.18, I2 = 0%). As far as cardiac arrhythmias are concerned, DPP-4 inhibitors did not significantly affect the risk for atrial fibrillation(RR = 0.95, 95%CI: 0.78-1.17, I2 = 0%), while they were associated with a significant increase in the risk for atrial flutter, equal to 52%(RR = 1.52, 95%CI: 1.03-2.24, I2 = 0%). DPP-4 inhibitors did not have a significant impact on the risk for any of the rest assessed cardiac arrhythmias.CONCLUSION DPP-4 inhibitors do not seem to confer any significant cardiovascular benefit for patients with T2 DM, while they do not seem to be associated with a significant risk for any major cardiac arrhythmias, except for atrial flutter. Therefore, this drug class should not be the treatment of choice for patients with established cardiovascular disease or multiple risk factors, except for those cases when newer antidiabetics(glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter-2 inhibitors) are not tolerated, contraindicated or not affordable for the patient.     

Glycemic control and safety in Chinese patients with type 2 diabetes mellitus who switched from premixed insulin to insulin glargine plus oral antidiabetics: a large,prospective, observational study

In some circumstances, the premixed insulin should be switched to alternative therapy. The effectiveness and the safety of switching from premixed insulin to insulin glargine plus oral antidiabetic drugs (OADs) in Chinese patients with type 2 diabetes mellitus (T2DM) have not been clarified and, hence, will be assessed in this study. Chinese patients with T2DM (2013 men and women aged 18–75 years) who had received premixed insulin ± OADs for ≥3 months with glycated hemoglobin (HbA1c) ≤ 10% were enrolled in a prospective, observational study conducted at 53 hospitals across China. At baseline and at the discretion of the physician, patients switched from premixed insulin to insulin glargine plus OADs. Changes in HbA1c, fasting plasma glucose (FPG), 2‐hour postprandial glucose (PPG), treatment satisfaction, and the incidence of hypoglycemia were assessed for 16 weeks. In total, 1850 patients completed the study. Mean HbA1c level for the group decreased significantly (from 7.8% ± 1.2% at week 1 to 7.0% ± 1.0% at week 16; P  < .0001), and 55.2% of patients achieved HbA1c < 7% at week 16. Mean FPG and 2‐hour PPG decreased significantly (−1.4 ± 2.2 and −2.1 ± 3.9 mmol/L, respectively; both P  < .0001), whereas patient satisfaction improved significantly. Adverse events were reported in 18.7% of patients. Chinese patients with T2DM who switched from premixed insulin to insulin glargine plus OADs achieved significantly improved glycemic control and treatment satisfaction with a low incidence of hypoglycemia. Patients who are most likely to achieve the HbA1c target less than 7% are younger, have shorter disease duration, and have lower baseline HbA1c and FPG levels.     

Cancer mortality reduction and metformin: a retrospective cohort study in type 2 diabetic patients

Aims: Few studies suggest that metformin decreases cancer mortality in type‐2 diabetic patients (T2DP). We explored the association between the type and duration of antidiabetic therapies and cancer and other‐than‐cancer mortality in a T2DP cohort, taking into account the competing risks between different causes of death and multiple potential confounding effects. The mortality rates were compared with the general population from the same area. Methods: In 1995, all T2DP (n = 3685) at our diabetes clinic in Turin (～12% of all T2DP in the city), without cancer at baseline, were identified. Vital status was assessed after a mean 4.5‐year follow‐up. Results: Metformin users had greater adiposity, while insulin users had more co‐morbidities. All‐cause‐ and cancer‐related deaths occurred in: 9.2 and 1.6% of metformin users, 13.1 and 3.0% of sulfonylureas users and 26.8 and 4.8% of insulin users, respectively. In a Cox regression model for competing risks, adjusted for propensity score, metformin users showed a lower cancer mortality risk [hazard ratio (HR) = 0.56; 95% confidence interval (CI) 0.34–0.94], while insulin was positively associated with other‐than‐cancer mortality (HR = 1.56; 95%CI 1.22–1.99). Each 5‐year metformin exposure was associated with a reduction in cancer death by 0.73, whereas every 5‐year insulin exposure was associated with 1.25‐fold increase in other‐than‐cancer death. Standardized mortality ratios for cancer and other‐than‐cancer mortality in metformin users were 43.6 (95%CI 25.8–69.0) and 99.1 (95%CI 79.3–122.5), respectively, in comparison with the general population. Conclusions: Metformin users showed a lower risk of cancer‐related mortality than not users or patients on diet only; this may represent another reason to choose metformin as a first‐line therapy in T2DP.     

DPP-4抑制剂的作用机制及在2型糖尿病治疗中的应用

α及母细胞功能障碍在2型糖尿病的发生中发挥重要作用.二肽基肽酶4( DPP-4)抑制剂是一类基于肠促胰素的新型的口服降糖药物,通过增加内源性活性胰升糖素样肽-1( GLP-1)及葡萄糖依赖性促胰岛素分泌多肽(GIP)水平改善α及β细胞功能障碍,表现为α及β细胞对葡萄糖的敏感性增加,葡萄糖依赖性地促进胰岛素分泌并抑制胰升糖素分泌.同时还具有增加胰岛素敏感性及调节血脂代谢等胰腺外作用.并具有较少发生低血糖,对体重的影响中性,不影响胃排空等特点.临床研究证实其无论单药还是与其他药物联合使用均具有较高的有效性及良好的安全性和耐受性.     

Diabetes and cancer: two diseases with obesity as a common risk factor

There is a growing body of evidence to support a connection between diabetes (predominantly type 2), obesity and cancer. Multiple meta‐analyses of epidemiological data show that people with diabetes are at increased risk of developing many different types of cancers, along with an increased risk of cancer mortality. Several pathophysiological mechanisms for this relationship have been postulated, including insulin resistance and hyperinsulinaemia, enhanced inflammatory processes, dysregulation of sex hormone production and hyperglycaemia. In addition to these potential mechanisms, a number of common risk factors, including obesity, may be behind the association between diabetes and cancer. Indeed, obesity is associated with an increased risk of cancer and diabetes. Abdominal adiposity has been shown to play a role in creating a systemic pro‐inflammatory environment, which could result in the development of both diabetes and cancer. Here, we examine the relationship between diabetes, obesity and cancer, and investigate the potential underlying causes of increased cancer risk in individuals with diabetes. Current treatment recommendations for reducing the overall disease burden are also explored and possible areas for future research are considered.     

二甲双胍联合二肽基肽酶4抑制剂治疗未达标的2型糖尿病患者应用格列喹酮的疗效研究

目的 比较格列喹酮、预混胰岛素对二甲双胍联合二肽基肽酶4抑制剂(DPP4I)血糖控制不佳的患者降糖效果.方法 选取2017年10月至2019年9月于天津市第四中心医院就诊的应用二甲双胍和DPP4I控制血糖不佳的2型糖尿病患者280例为研究对象,分为格列喹酮和预混胰岛素组,比较两组血糖、体重变化及低血糖情况.结果 格列喹...     

Glycaemic efficacy of glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors as add-on therapy to metformin in subjects with type 2 diabetes-a review and meta analysis

Aims: During recent years, two strategies of incretin-based therapy [glucagon-like peptide-1 (GLP-1) receptor agonism and dipeptidyl peptidase-4 (DPP-4) inhibition] have entered the market for pharmacological management of type 2 diabetes. A main indication for this therapy is as add-on to on-going metformin therapy in subjects with type 2 diabetes who have insufficient glycaemic control with metformin alone. The aim of this study was to compare improvements in glycaemic control and changes in body weight, as well as adverse events, in comparable studies with incretin-based therapy as add-on to metformin. Methods: Studies having a duration of 16-30 weeks were identified from PubMed. Results: A total of 27 study groups in 21 studies fulfilled the criteria of examining incretin-based therapy as add-on to metformin at clinically recommended doses in patients with type 2 diabetes for 16-30 weeks; 7 of these used a short-acting GLP-1 receptor agonist (exenatide BID), 7 used longer acting GLP-1 receptor agonists (liraglutide or exenatide LAR), whereas 14 studies examined DPP-4 inhibitors. In all studies, incretin-based therapy reduced HbA1c concentrations. The reduction in HbA1c was significantly greater in study groups with long-acting GLP-1 receptor agonists than with the other two groups (both p < 0.001), whereas there were no differences between exenatide BID and DPP-4 inhibitors. Across all study groups, there was a negative linear correlation between baseline HbA1c and change in HbA1c (r = -0.70; p < 0.001). Fasting glucose also fell significantly more in study groups given liraglutide or exenatide LAR than in those given exenatide BID or DPP-4 inhibitors (both p < 0.001). Furthermore, body weight was reduced by a similar extent in the two groups with GLP-1 receptor agonists and was not significantly altered in the groups with DPP-4 inhibitors. Lipids, blood pressure and heart rate were not reported consistently, which did not allow general conclusions. Adverse events were rare, apart from increased incidence of nausea and vomiting with GLP-1 receptor agonists. Conclusion: Incretin-based therapy efficiently improves glycaemia when added to metformin in patients with type 2 diabetes, and within 16-30 weeks there is a more pronounced reduction in HbA1c with long-acting GLP-1 receptor agonists (liraglutide and exenatide LAR) than with exenatide BID and DPP-4 inhibitors, although the magnitude of the effect is dependent on the baseline values. Both strategies appear to be associated with a very low risk of adverse events, including hypoglycaemia. Finally, the injectable GLP-1 receptor agonists also reduce body weight (whereas the DPP-4 inhibitors are weight neutral) but are also associated with a greater incidence of gastrointestinal side effects and a tendency to increase heart rate.