Association between first-line monotherapy with sulphonylurea versus metformin and risk of all-cause mortality and cardiovascular events: a retrospective, observational study

GCMS fingerprints and phenolic extracts of Allium sativum inhibit key enzymes associated with type 2 diabetes

Objectives

Inhibition of carbohydrate digestion enzymes (α-amylase and α-glucosidase) has been reported in studies as a therapeutic approach for the management or treatment of type 2 diabetes mellitus, owing to its potential to decrease postprandial hyperglycemia. The anti-diabetic potential of Allium sativum (also known as garlic) against diabetes mellitus has been established. Therefore, in this study, we assessed the antidiabetic potential of A. sativum using in vitro enzyme assays after which we explored computational modelling approach using the quantified GC-MS identities to unravel the key bioactive compounds responsible for the anti-diabetic potential.

Methods

We used in vitro enzyme inhibition assays (α-amylase and α-glucosidase) to evaluate antidiabetic potential and subsequently performed gas chromatography-mass spectroscopy (GC-MS) to identify and quantify the bioactive compounds of the plant extract. The identified bioactive compounds were subjected to in silico docking and pharmacokinetic assessment.

Results

A. sativum phenolic extract showed high dose-dependent inhibition of α-amylase and α-glucosidase (p < 0.05). Interestingly, the extract inhibited α-glucosidase with a half maximal inhibitory concentration of 53.75 μg/mL, a value higher than that obtained for the standard acarbose. Docking simulation revealed that morellinol and phentolamine were the best binders of α-glucosidase, with mean affinity values of -7.3 and -7.1 kcal/mol, respectively. These compounds had good affinity toward active site residues of the enzyme, and excellent drug-like and pharmacokinetic properties supporting clinical applications.

Conclusions

Our research reveals the potential of A. sativum as a functional food for the management of type 2 diabetes, and suggests that morellinol and phentolamine may be the most active compounds responsible for this anti-diabetic prowess. Therefore these compounds require further clinical asessment to demonstrate their potential for drug development.

Effect of metformin on adverse outcomes in T2DM patients: Systemic review and meta-analysis of observational studies

Background

The cardiovascular protection effect of metformin on patients with type 2 diabetes mellitus (T2DM) remains inconclusive. This systemic review and meta-analysis were to estimate the effect of metformin on mortality and cardiovascular events among patients with T2DM.

Methods

A search of the Pubmed and EMBASE databases up to December 2021 was performed. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled by a random-effects model with an inverse variance method.

Results

A total of 39 studies involving 2473009 T2DM patients were adopted. Compared to non-metformin therapy, the use of metformin was not significantly associated with a reduced risk of major adverse cardiovascular event (MACE) (HR = 1.06, 95%CI 0.91–1.22; I² = 82%), hospitalization (HR = 0.85, 95%CI 0.64–1.13; I² = 98%), heart failure (HR = 0.86, 95%CI 0.60–1.25; I² = 99%), stroke (HR = 1.16, 95%CI 0.88–1.53; I² = 84%), and risk of AMI (HR = 0.88, 95%CI 0.69–1.14; I² = 88%) in T2DM patients. Metformin was also not associated with significantly lowered risk of MACE compared to dipeptidyl peptidase-4 inhibitor (DPP-4i) in T2DM patients (HR = 0.95, 95%CI 0.73–1.23; I² = 84%).

Conclusions

The effect of metformin on some cardiovascular outcomes was not significantly better than the non-metformin therapy or DPP-4i in T2DM patients based on observational studies.

A Clinical Perspective of the Multifaceted Mechanism of Metformin in Diabetes, Infections, Cognitive Dysfunction, and Cancer

In type 2 diabetes, ecological and lifecourse factors may interact with the host microbiota to influence expression of his/her genomes causing perturbation of interconnecting biological pathways with diverse clinical course. Metformin is a plant-based or plant-derived medicinal product used for the treatment of type 2 diabetes for over 60 years and is an essential drug listed by the World Health Organization. By reducing mitochondrial oxidative phosphorylation and adenosine triphosphate (ATP) production, metformin increased AMP (adenosine monophosphate)-activated protein kinase (AMPK) activity and altered cellular redox state with reduced glucagon activity, endogenous glucose production, lipogenesis, and protein synthesis. Metformin modulated immune response by directly reducing neutrophil to lymphocyte ratio and improving the phagocytic function of immune cells. By increasing the relative abundance of mucin-producing and short-chain-fatty-acid-producing gut microbes, metformin further improved the host inflammatory and metabolic milieu. Experimentally, metformin promoted apoptosis and reduced proliferation of cancer cells by reducing their oxygen consumption and modulating the microenvironment. Both clinical and mechanistic studies support the pluripotent effects of metformin on reducing cardiovascular–renal events, infection, cancer, cognitive dysfunction, and all-cause death in type 2 diabetes, making this low-cost medication a fundamental therapy for individualization of other glucose-lowering drugs in type 2 diabetes. Further research into the effects of metformin on cognitive function, infection and cancer, especially in people without diabetes, will provide new insights into the therapeutic value of metformin in our pursuit of prevention and treatment of ageing-related as well as acute and chronic diseases beyond diabetes.

Cardiovascular Safety and Benefits of Noninsulin Antihyperglycemic Drugs for the Treatment of Type 2 Diabetes Mellitus-Part 1

Cardiovascular disease (CVD) is a major contributor to the morbidity and mortality associated with type 2 diabetes mellitus (T2DM). With T2DM growing in pandemic proportions, there will be profound healthcare implications of CVD in person with diabetes. The ideal drugs to improve outcomes in T2DM are those having antiglycemic efficacy in addition to cardiovascular (CV) safety, which has to be determined in appropriately designed CV outcome trials as mandated by regulatory agencies. Available evidence is largely supportive of metformin's CV safety and potential CVD risk reduction effects, whereas sulfonylureas are either CV risk neutral or are associated with variable CVD risk. Pioglitazone was also associated with improved CVD risk in patients with diabetes. The more recent antihyperglycemic medications have shown promise with regards to CVD risk reduction in T2DM patients at a high CV risk. Glucagon-like peptide-1 receptor agonists, a type of incretin-based therapy, were associated with better CV outcomes and mortality in T2DM patients, leading to the Food and Drug Administration approval of liraglutide to reduce CVD risk in high-risk T2DM patients. Ongoing and planned randomized controlled trials of the newer drugs should clarify the possibility of class effects, and of CVD risk reduction benefits in low-moderate CV risk patients. While metformin remains the first-line antiglycemic therapy in T2DM, glucagon-like peptide-1 receptor agonists should be appropriately prescribed in T2DM patients with baseline CVD or in those at a high CVD risk to improve CV outcomes. Dipeptidyl peptidase-4 inhibitors and sodium-glucose cotransporter-2 inhibitors are discussed in the second part of this review.

Interactions Between Therapeutics for Metabolic Disease, Cardiovascular Risk Factors, and Gut Microbiota

With improved standards of living, the incidence of multiple metabolic disorders has increased year by year, especially major risk factors for cardiovascular disease such as hyperglycemia and hyperlipidemia, continues to increase. Emerging epidemiological data and clinical trials have shown the additional protective effects of some metabolic therapy drugs against cardiovascular diseases. A series of studies have found that these drugs may work by modulating the composition of gut microbiota. In this review, we provide a brief overview of the contribution of the gut microbiota to both metabolic disorders and cardiovascular diseases, as well as the response of gut microbiota to metabolic therapy drugs with cardiovascular benefits. In this manner, we link the recent advances in microbiome studies on metabolic treatment drugs with their cardiovascular protective effects, suggesting that intestinal microorganisms may play a potential role in reducing cardiovascular risk factors. We also discuss the potential of microorganism-targeted therapeutics as treatment strategies for preventing and/or treating cardiovascular disease and highlight the need to establish causal links between therapeutics for metabolic diseases, gut microbiota modulation, and cardiovascular protection.

Metformin Use and Risk of All-Cause Mortality and Cardiovascular Events in Patients With Chronic Kidney Disease-A Systematic Review and Meta-Analysis

Background

To evaluate whether metformin use assuredly alters overall all-cause death in patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD).

Methods

Pubmed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials were systematically searched from inception to Feb. 29, 2020 with no language restriction. All related articles comparing all-cause death of T2DM and CKD patients after metformin use (monotherapy or combination) versus non-metformin treatment were identified. Pooled risk ratios (RR) and 95% confidence intervals (CI) were computed using random-effects models regardless of the heterogeneity quantified by Cochrane χ2 and I2 statistics.

Results

Totally 13 studies (9 cohort studies [CSs], 3 subanalyses or post-hoc analyses of randomized controlled trials [RCTs], and 1 nested case-control article) involving 303,540 patients were included. Metformin-based treatments relative to any other measure displayed significantly lower risks of all-cause mortality (Pooled RRs 0.71, 95%CI 0.61 to 0.84; I2 = 79.0%) and cardiovascular events (Pooled RRs 0.76, 95%CI 0.60 to 0.97; I2 = 87.0%) in CKD patients at stage G1-3, with substantial heterogeneity. Metformin use was not significantly related with these end points in advanced CKD patients.

Conclusions

Metformin use is connected with significantly less risks of all-cause mortality and cardiovascular events in patients with T2DM and mild/moderate CKD. However, RCTs with large sample sizes are warranted in the future to assess whether these key benefits extend to later stages of CKD by dose adjustment.

Scientific independence and objectivity: many questions linger about treatment of type 2 diabetes, such as scientific study design, optimal glucose control and the safety of injecting exogenous insulin

Whilst clinical guidelines exist for the treatment of people with type 2 diabetes, many underlying assumptions are still not qualified by convincing evidence. In this commentary, it is argued that fundamental issues still cloud clinical practice, such as biases in the design of clinical studies, the association between glucose control & clinical outcomes, and the safety of exposure to exogenous insulin and other glucose-lowering drugs. Relevant scientific evidence and alternative opinions about important issues continue to be largely ignored, and no effort has been made to resolve these questions. This may have had serious consequences, such as stifling innovation because there are no further benefits to be achieved in relation to glucose control.

Real-world Evaluation of glycemic control and hypoglycemic Events among type 2 Diabetes mellitus study (REEDS): a multicentre, cross-sectional study in Thailand

OBJECTIVE

Patients with type 2 diabetes mellitus (T2DM) often experience hypoglycaemia and weight gain due to treatment side effects. Sulfonylureas (SU) and the combination of SU and metformin (SU+MET) were the most common monotherapy and combination therapies used in Thailand tertiary care hospitals. This study aimed to assess the glycaemic goal attainment rates, hypoglycaemic episodes, weight gain and treatment compliance among patients with T2DM receiving SU or SU+MET.

RESEARCH DESIGN AND METHODS

A multicentre cross-sectional survey and retrospective review was conducted in five tertiary care hospitals, Thailand. Patients with T2DM aged ≥30 years were included consecutively during a 12-month period. Glycaemic control, experiences of hypoglycaemia, weight gain and compliance were evaluated. Glycaemic goal attainment was defined by HbA_1c level less than 7%.

RESULTS

Out of the 659 patients (mean age (±SD)), 65.5 (10.0) years and median duration of T2DM (IQR), 10 (5-15) years), 313 (47.5%) achieved the glycaemic goal. HbA_1c levels in the patients with goal attainment was significantly lower compared with those without (6.3%±0.5% vs 8.1%±1.2%, p<0.001). Goal attainment was significantly lower among patients treated with SU+MET than those treated with SU alone (43.5% vs 63.0%; OR 0.45, 95% CI 0.31, 0.66, p<0.001). A third of patients reported experiencing hypoglycaemia (30.7%) and weight gain (35.4%). Weight gain in the SU+MET group was lower than those receiving SU alone (33.1% vs 44.6%, p=0.015), but there was no difference in hypoglycaemic events. Major events in the previous 12 months were experienced by 68 patients, most commonly congestive heart failure and ischaemic heart disease. Approximately half of the patients (52.2%) reported not always taking their medication as prescribed.

CONCLUSIONS

Among patients with T2DM receiving SU or SU+MET, only about half of the patients achieved glycaemic goal and compliance with the treatment. Hypoglycaemia and weight gain posed a significant burden with risk of weight gain higher in the SU group.

Cardiovascular risk following metformin treatment in patients with type 2 diabetes mellitus: Results from meta-analysis

AIM

Pharmacologic therapy for T2DM has proven benefits in terms of reducing elevated blood glucose levels and reducing microvascular complications. However, the impact of metformin on adverse cardiovascular outcomes and cardiovascular mortality is less clear. We carried out this meta-analysis on all published studies to estimate the overall cardiovascular risk following metformin treatment in patients with T2DM.

METHODS

We searched the PubMed, Embase and CNKI (China National Knowledge Infrastructure) databases for all articles. The odds ratio (OR) corresponding to the 95% confidence interval (95% CI) was used to assess the cardiovascular risk following metformin treatment in patients with T2DM. The statistical heterogeneity among studies was assessed with the Q-test and I² statistics.

RESULTS

We collected 16 studies including 25 comparisons with 1,160,254 patients of type 2 diabetes mellitus and 701,843 patients of T2DM following metformin treatment. Our results found statistical evidence of significantly decreased cardiovascular risk to be associated with following treatment with metformin in patients with type 2 diabetes mellitus (OR = 0.57, 95% CI = 0.48-0.68) (shown in Table 1 and Fig. 2), both with the mortality (OR = 0.44, 95% CI = 0.34-0.57) and incidence (OR = 0.73, 95% CI = 0.59-0.90).

CONCLUSIONS

Our meta-analysis indicated that following metformin treatment in patients with T2DM was associated with decreased cardiovascular risk, both with the mortality and incidence. However, the heterogeneity among studies may potentially affect the final results.

Mechanisms of action of metformin with special reference to cardiovascular protection

Management guidelines continue to identify metformin as initial pharmacologic antidiabetic therapy of choice for people with type 2 diabetes without contraindications, despite recent randomized trials that have demonstrated significant improvements in cardiovascular outcomes with newer classes of antidiabetic therapies. The purpose of this review is to summarize the current state of knowledge of metformin's therapeutic actions on blood glucose and cardiovascular clinical evidence and to consider the mechanisms that underlie them. The effects of metformin on glycaemia occur mainly in the liver, but metformin-stimulated glucose disposal by the gut has emerged as an increasingly import site of action of metformin. Additionally, metformin induces increased secretion of GLP-1 from intestinal L-cells. Clinical cardiovascular protection with metformin is supported by three randomized outcomes trials (in newly diagnosed and late stage insulin-treated type 2 diabetes patients) and a wealth of observational data. Initial evidence suggests that cotreatment with metformin may enhance the impact of newer incretin-based therapies on cardiovascular outcomes, an important observation as metformin can be combined with any other antidiabetic agent. Multiple potential mechanisms support the concept of cardiovascular protection with metformin beyond those provided by reduced blood glucose, including weight loss, improvements in haemostatic function, reduced inflammation, and oxidative stress, and inhibition of key steps in the process of atherosclerosis. Accordingly, metformin remains well placed to support improvements in cardiovascular outcomes, from diagnosis and throughout the course of type 2 diabetes, even in this new age of improved outcomes in type 2 diabetes.

Metformin Use and Clinical Outcomes Among Patients With Diabetes Mellitus With or Without Heart Failure or Kidney Dysfunction

Background:

Metformin is first-line therapy for type 2 diabetes mellitus, although its effects on the cardiovascular system are unproved.

Methods:

In this post hoc analysis, patients in SAVOR-TIMI 53 (Saxagliptin and Cardiovascular Outcomes in Patients With Type 2 Diabetes Mellitus) with baseline biomarker samples (n=12 156) were classified as ever versus never taking metformin during the trial period. Associations between metformin exposure and outcomes were estimated with inverse probability of treatment weighting Cox modeling for the composite end point of cardiovascular death, myocardial infarction, or ischemic stroke, as well as cardiovascular death and all-cause mortality, with biomarkers included as covariates. Additional sensitivity analyses included propensity score matching and Cox multivariable models.

Results:

Of the 12 156 patients with baseline biomarker samples, 8971 (74%) had metformin exposure, 1611 (13%) had prior heart failure, and 1332 (11%) had at least moderate chronic kidney disease (estimated glomerular filtration rate ≤45 mL·min −1 ·1.73 m −2 ). Metformin use was associated with no difference in risk for the composite end point (hazard ratio for inverse probability of treatment weighting, 0.92 [95% CI, 0.76–1.11]) but lower risk of all-cause mortality (hazard ratio for inverse probability of treatment weighting, 0.75 [95% CI, 0.59–0.95]). There was no significant relationship between metformin use and these end points in patients with prior heart failure or moderate to severe chronic kidney disease.

Conclusions:

In a cohort of 12 156 patients with type 2 diabetes mellitus and high cardiovascular risk, metformin use was associated with lower rates of all-cause mortality, including after adjustment for clinical variables and biomarkers, but not lower rates of the composite end point of cardiovascular death, myocardial infarction, or ischemic stroke. This association was most apparent in patients without prior heart failure or moderate to severe chronic kidney disease.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01107886.

Effect of metformin on all-cause and cardiovascular mortality in patients with coronary artery diseases: a systematic review and an updated meta-analysis

BACKGROUND

Metformin is the most widely prescribed drug to lower glucose and has a definitive effect on the cardiovascular system. The goal of this systematic review and meta-analysis is to assess the effects of metformin on mortality and cardiac function among patients with coronary artery disease (CAD).

METHODS

Relevant studies reported before October 2018 was retrieved from databases including PubMed, EMBASE, Cochrane Library and Web of Science. Hazard ratio (HR) was calculated to evaluate the all-cause mortality, cardiovascular mortality and incidence of cardiovascular events (CV events), to figure out the level of left ventricular ejection fraction (LVEF), creatine kinase MB (CK-MB), type B natriuretic peptide (BNP) and to compare the average level of low density lipoprotein (LDL).

RESULTS

In this meta-analysis were included 40 studies comprising 1,066,408 patients. The cardiovascular mortality, all-cause mortality and incidence of CV events were lowered to adjusted HR (aHR) = 0.81, aHR = 0.67 and aHR = 0. 83 respectively after the patients with CAD were given metformin. Subgroup analysis showed that metformin reduced all-cause mortality in myocardial infarction (MI) (aHR = 0.79) and heart failure (HF) patients (aHR = 0.84), the incidence of CV events in HF (aHR = 0.83) and type II diabetes mellitus (T2DM) patients (aHR = 0.83), but had no significant effect on MI (aHR = 0.87) and non-T2DM patients (aHR = 0.92). Metformin is superior to sulphonylurea (aHR = 0.81) in effects on lowering the incidence of CV events and in effects on patients who don't use medication. The CK-MB level in the metformin group was lower than that in the control group standard mean difference (SMD) = - 0.11). There was no significant evidence that metformin altered LVEF (MD = 2.91), BNP (MD = - 0.02) and LDL (MD = - 0.08).

CONCLUSION

Metformin reduces cardiovascular mortality, all-cause mortality and CV events in CAD patients. For MI patients and CAD patients without T2DM, metformin has no significant effect of reducing the incidence of CV events. Metformin has a better effect of reducing the incidence of CV events than sulfonylureas.

Metformin and second- or third-generation sulphonylurea combination therapy for adults with type 2 diabetes mellitus

BACKGROUND

The number of people with type 2 diabetes mellitus (T2DM) is increasing worldwide. The combination of metformin and sulphonylurea (M+S) is a widely used treatment. Whether M+S shows better or worse effects in comparison with other antidiabetic medications for people with T2DM is still controversial.

OBJECTIVES

To assess the effects of metformin and sulphonylurea (second- or third-generation) combination therapy for adults with type 2 diabetes mellitus.

SEARCH METHODS

We updated the search of a recent systematic review from the Agency for Healthcare Research and Quality (AHRQ). The updated search included CENTRAL, MEDLINE, Embase, ClinicalTrials.gov and WHO ICTRP. The date of the last search was March 2018. We searched manufacturers' websites and reference lists of included trials, systematic reviews, meta-analyses and health technology assessment reports. We asked investigators of the included trials for information about additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) randomising participants 18 years old or more with T2DM to M+S compared with metformin plus another glucose-lowering intervention or metformin monotherapy with a treatment duration of 52 weeks or more.

DATA COLLECTION AND ANALYSIS

Two review authors read all abstracts and full-text articles and records, assessed risk of bias and extracted outcome data independently. We used a random-effects model to perform meta-analysis, and calculated risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We assessed the certainty of the evidence using the GRADE instrument.

MAIN RESULTS

We included 32 RCTs randomising 28,746 people. Treatment duration ranged between one to four years. We judged none of these trials as low risk of bias for all 'Risk of bias' domains. Most important events per person were all-cause and cardiovascular mortality, serious adverse events (SAE), non-fatal stroke (NFS), non-fatal myocardial infarction (MI) and microvascular complications. Most important comparisons were as follows:Five trials compared M+S (N = 1194) with metformin plus a glucagon-like peptide 1 analogue (N = 1675): all-cause mortality was 11/1057 (1%) versus 11/1537 (0.7%), risk ratio (RR) 1.15 (95% confidence interval (CI) 0.49 to 2.67); 3 trials; 2594 participants; low-certainty evidence; cardiovascular mortality 1/307 (0.3%) versus 1/302 (0.3%), low-certainty evidence; serious adverse events (SAE) 128/1057 (12.1%) versus 194/1537 (12.6%), RR 0.90 (95% CI 0.73 to 1.11); 3 trials; 2594 participants; very low-certainty evidence; non-fatal myocardial infarction (MI) 2/549 (0.4%) versus 6/1026 (0.6%), RR 0.57 (95% CI 0.12 to 2.82); 2 trials; 1575 participants; very low-certainty evidence.Nine trials compared M+S (N = 5414) with metformin plus a dipeptidyl-peptidase 4 inhibitor (N = 6346): all-cause mortality was 33/5387 (0.6%) versus 26/6307 (0.4%), RR 1.32 (95% CI 0.76 to 2.28); 9 trials; 11,694 participants; low-certainty evidence; cardiovascular mortality 11/2989 (0.4%) versus 9/3885 (0.2%), RR 1.54 (95% CI 0.63 to 3.79); 6 trials; 6874 participants; low-certainty evidence; SAE 735/5387 (13.6%) versus 779/6307 (12.4%), RR 1.07 (95% CI 0.97 to 1.18); 9 trials; 11,694 participants; very low-certainty evidence; NFS 14/2098 (0.7%) versus 8/2995 (0.3%), RR 2.21 (95% CI 0.74 to 6.58); 4 trials; 5093 participants; very low-certainty evidence; non-fatal MI 15/2989 (0.5%) versus 13/3885 (0.3%), RR 1.45 (95% CI 0.69 to 3.07); 6 trials; 6874 participants; very low-certainty evidence; one trial in 64 participants reported no microvascular complications were observed (very low-certainty evidence).Eleven trials compared M+S (N = 3626) with metformin plus a thiazolidinedione (N = 3685): all-cause mortality was 123/3300 (3.7%) versus 114/3354 (3.4%), RR 1.09 (95% CI 0.85 to 1.40); 6 trials; 6654 participants; low-certainty evidence; cardiovascular mortality 37/2946 (1.3%) versus 41/2994 (1.4%), RR 0.78 (95% CI 0.36 to 1.67); 4 trials; 5940 participants; low-certainty evidence; SAE 666/3300 (20.2%) versus 671/3354 (20%), RR 1.01 (95% CI 0.93 to 1.11); 6 trials; 6654 participants; very low-certainty evidence; NFS 20/1540 (1.3%) versus 16/1583 (1%), RR 1.29 (95% CI 0.67 to 2.47); P = 0.45; 2 trials; 3123 participants; very low-certainty evidence; non-fatal MI 25/1841 (1.4%) versus 21/1877 (1.1%), RR 1.21 (95% CI 0.68 to 2.14); P = 0.51; 3 trials; 3718 participants; very low-certainty evidence; three trials (3123 participants) reported no microvascular complications (very low-certainty evidence).Three trials compared M+S (N = 462) with metformin plus a glinide (N = 476): one person died in each intervention group (3 trials; 874 participants; low-certainty evidence); no cardiovascular mortality (2 trials; 446 participants; low-certainty evidence); SAE 34/424 (8%) versus 27/450 (6%), RR 1.68 (95% CI 0.54 to 5.21); P = 0.37; 3 trials; 874 participants; low-certainty evidence; no NFS (1 trial; 233 participants; very low-certainty evidence); non-fatal MI 2/215 (0.9%) participants in the M+S group; 2 trials; 446 participants; low-certainty evidence; no microvascular complications (1 trial; 233 participants; low-certainty evidence).Four trials compared M+S (N = 2109) with metformin plus a sodium-glucose co-transporter 2 inhibitor (N = 3032): all-cause mortality was 13/2107 (0.6%) versus 19/3027 (0.6%), RR 0.96 (95% CI 0.44 to 2.09); 4 trials; 5134 participants; very low-certainty evidence; cardiovascular mortality 4/1327 (0.3%) versus 6/2262 (0.3%), RR 1.22 (95% CI 0.33 to 4.41); 3 trials; 3589 participants; very low-certainty evidence; SAE 315/2107 (15.5%) versus 375/3027 (12.4%), RR 1.02 (95% CI 0.76 to 1.37); 4 trials; 5134 participants; very low-certainty evidence; NFS 3/919 (0.3%) versus 7/1856 (0.4%), RR 0.87 (95% CI 0.22 to 3.34); 2 trials; 2775 participants; very low-certainty evidence; non-fatal MI 7/890 (0.8%) versus 8/1374 (0.6%), RR 1.43 (95% CI 0.49 to 4.18; 2 trials); 2264 participants; very low-certainty evidence; amputation of lower extremity 1/437 (0.2%) versus 1/888 (0.1%); very low-certainty evidence.Trials reported more hypoglycaemic episodes with M+S combination compared to all other metformin-antidiabetic agent combinations. Results for M+S versus metformin monotherapy were inconclusive. There were no RCTs comparing M+S with metformin plus insulin. We identified nine ongoing trials and two trials are awaiting assessment. Together these trials will include approximately 16,631 participants.

AUTHORS' CONCLUSIONS

There is inconclusive evidence whether M+S combination therapy compared with metformin plus another glucose-lowering intervention results in benefit or harm for most patient-important outcomes (mortality, SAEs, macrovascular and microvascular complications) with the exception of hypoglycaemia (more harm for M+S combination). No RCT reported on health-related quality of life.

Positive Impact of a Pilot Pharmacist-Run Diabetes Pharmacotherapy Clinic in Solid-Organ Transplant Recipients

PURPOSE

Post-transplant diabetes mellitus (PTDM) can lead to significant morbidity and cardiovascular death with a functioning graft. A paucity of literature exists regarding glycemic control in solid-organ transplant (SOT) recipients, including pharmacist management of PTDM. This study aimed to assess the impact of pharmacist interventions on diabetes management in a pharmacist-run PTDM clinic.

METHODS

This was a single-center, prospective, observational study of 24 adult SOT recipients enrolled in a pilot pharmacist-managed PTDM clinic from 1 January to 30 June 2015.

RESULTS

Improvements were realized in markers of glycemic control, including changes in A1C, average daily self-monitoring of blood glucose (SMBG) results, fasting SMBG results, and pre-lunch SMBG results from enrollment through at least 3 months of follow-up. Median A1C decreased significantly from 8.05% (interquartile range [IQR] 6.33-11.75) at baseline to 6.45% (IQR 6.05-7.3) at the last follow-up encounter (P = 0.0010). Average daily SMBG results decreased significantly from a median of 191 mg/dL (IQR 138-232 mg/dL) at baseline to 125 mg/dL (IQR 111-167 mg/dL) at the final encounter (P = 0.0023). Median fasting and pre-lunch SMBG results decreased significantly from 153 mg/dL (IQR 117-208 mg/dL) at baseline to 120 mg/dL (IQR 102-134 mg/dL) (P = 0.0064) and from 212 mg/dL (IQR 159-258 mg/dL) to 122 mg/dL (IQR 110-169 mg/dL) (P = 0.0161), respectively. Changes from baseline in other SMBG values, lipid levels, and BMI were not statistically significant.

CONCLUSION

The results of our study demonstrate that a pharmacist-managed PTDM clinic can significantly affect glycemic control in SOT recipients.

Risk of a first-ever acute myocardial infarction and all-cause mortality with sulphonylurea treatment: A population-based cohort study

We investigated the association between the current use of individual sulphonylureas and the risk of a first-ever acute myocardial infarction (AMI) and all-cause mortality, in a population-based cohort study, using primary care data from the Clinical Practice Research Datalink database (2004-2012). New users (N = 121 869), aged ≥18 years, with at least one prescription for a non-insulin antidiabetic agent were included. The first prescription defined start of follow-up. Time-dependent Cox proportional hazard models were used to estimate the risk of a first-ever AMI and all-cause mortality associated with the use of individual sulphonylureas, and other non-insulin glucose-lowering drugs. No differences in risk of a first-ever AMI (adjusted hazard ratio [HR] 1.02, 95% confidence interval [CI] 0.70-1.50) or all-cause mortality (adjusted HR 0.97, 95% CI 0.80-1.17) were observed when comparing gliclazide use with non-gliclazide sulphonylurea use. Similar results were found for each individual sulphonylurea. As evidence is accumulating that gliclazide is no safer than other sulphonylureas, current guidelines suggesting superiority should be carefully evaluated.

Sulfonylureas as Initial Treatment for Type 2 Diabetes and the Risk of Severe Hypoglycemia

PURPOSE

The magnitude of the risk of severe hypoglycemia associated with sulfonylureas as the initial treatment for type 2 diabetes in the real-world setting is unknown. We assessed the risk of severe hypoglycemia associated with initiating monotherapy with sulfonylurea compared with metformin for the treatment of type 2 diabetes.

METHODS

By using the UK Clinical Practice Research Datalink and Hospital Episode Statistics linked to the Office for National Statistics, we identified a cohort of patients with type 2 diabetes who initiated sulfonylureas or metformin monotherapy between April 1, 1998, and December 31, 2012, with follow-up until December 31, 2013. Sulfonylurea users were matched one-to-one to metformin users by high-dimensional propensity scores. Hazard ratios (HRs) and 95% confidence intervals (CIs) of severe hypoglycemia, defined as requiring hospitalization, were estimated using Cox proportional hazards models comparing sulfonylureas with metformin monotherapy.

RESULTS

The study cohort consisted of 14,012 initiators of sulfonylureas matched to 14,012 initiators of metformin. The mean treated follow-up time was 1.41 (standard deviation, 1.84) years. Use of sulfonylurea was associated with an elevated incidence of severe hypoglycemia compared with metformin as the initiating monotherapy for type 2 diabetes (incidence rate, 2.4/1000 person-years; 95% CI, 1.90-2.90; HR, 4.53; 95% CI, 2.76-7.45).

CONCLUSIONS

Sulfonylureas, when prescribed as the initiating monotherapy for the treatment of type 2 diabetes, is associated with a 4.5-fold increase in the risk of severe hypoglycemia. Given the negative consequences of this outcome, clinicians should consider alternative hypoglycemic agents when metformin is not tolerated or contraindicated.

Mortality Associated with Metformin Versus Sulfonylurea Initiation: A Cohort Study of Veterans with Diabetes and Chronic Kidney Disease

BACKGROUND

For patients with type 2 diabetes and chronic kidney disease (CKD), high-quality evidence about the relative benefits and harms of oral glucose-lowering drugs is limited.

OBJECTIVE

To evaluate whether mortality risk differs after the initiation of monotherapy with either metformin or a sulfonylurea in Veterans with type 2 diabetes and CKD.

DESIGN

Observational, national cohort study in the Veterans Health Administration (VHA).

PARTICIPANTS

Veterans who received care from the VHA for at least 1 year prior to initiating monotherapy treatment for type 2 diabetes with either metformin or a sulfonylurea between 2004 and 2009.

MAIN MEASURES

Metformin and sulfonylurea use was assessed from VHA electronic pharmacy records. The CKD-EPI equation was used to estimate glomerular filtration rate (eGFR). The outcome of death from January 1, 2004, through December 31, 2009, was assessed from VHA Vital Status files.

KEY RESULTS

Among 175,296 new users of metformin or a sulfonylurea monotherapy, 5121 deaths were observed. In primary analyses adjusted for all measured potential confounding factors, metformin monotherapy was associated with a lower mortality hazard ratio (HR) compared with sulfonylurea monotherapy across all ranges of eGFR evaluated (HR ranging from 0.59 to 0.80). A secondary analysis of mortality risk differences favored metformin across all eGFR ranges; the greatest risk difference was observed in the eGFR category 30-44 mL/min/1.73m² (12.1 fewer deaths/1000 person-years, 95% CI 5.2-19.0).

CONCLUSIONS

Initiation of metformin versus a sulfonylurea among individuals with type 2 diabetes and CKD was associated with a substantial reduction in mortality, in terms of both relative and absolute risk reduction. The largest absolute risk reduction was observed among individuals with moderately-severely reduced eGFR (30-44 mL/min/1.73m²).

The Infamous, Famous Sulfonylureas and Cardiovascular Safety: Much Ado About Nothing?

PURPOSE OF REVIEW

Sulfonylureas (SUs) are one of the most commonly used glucose-lowering agents worldwide. While their efficacy is undisputed, their cardiovascular safety has been debated since the 1970's.

RECENT FINDINGS

With no dedicated cardiovascular studies to definitively answer this question, observational studies and meta-analyses abound and have reported divergent results, fueling the controversy. Studies that compared SUs to metformin or newer agents, like GLP-1 agonists and SGLT2 inhibitors, suggest a difference in cardiovascular events, yet this is likely the result of beneficial effects of the latter. Studies comparing SUs to other agents have been reassuring. SUs remain a common choice of treatment for patients with type 2 diabetes due to their exceptional value. They are effective at lowering glucose and thus contributing to the prevention of microvascular complications. Weight gain and hypoglycemia are their main side effects, although less severe when compared to insulin treatment. Their cardiovascular safety will remain a controversial topic due to lack of conclusive data, but there is no definitive evidence of harm with the second-generation agents.

Dipeptidyl Peptidase-4 Inhibitors and Risk of Heart Failure in Patients With Type 2 Diabetes Mellitus: A Population-Based Cohort Study

BACKGROUND

The association between dipeptidyl-peptidase IV inhibitors (DPP-4i) and heart failure (HF) remains unclear. In 1 randomized controlled trial and some observational studies, DPP-4i reportedly increased the risk of HF, but 2 other randomized controlled trials and observational studies have shown no such risk. Here, we evaluated the risk of HF and cardiovascular outcomes of DPP-4i compared with sulfonylureas.

METHODS AND RESULTS

A population-based retrospective cohort study was conducted using the Korean Health Insurance Review and Assessment Service database from January 1, 2009, to December 31, 2015. Incident users of sulfonylurea and DPP-4i who were not prescribed the comparator drug in the year before treatment initiation were included. DPP-4i-treated and sulfonylurea-treated patients were matched on propensity score, calculated with >40 variables. The risk of hospitalization for HF was evaluated with a Cox proportional hazards model in 255 691 matched pairs. Analyses were conducted in the total patient population and in both strata divided by the presence of cardiovascular disease during the baseline period. The hazard ratios (HRs) of hospitalization for HF for DPP-4i-treated patients were 0.78 (95% confidence interval [CI], 0.67-0.86) in all of the patients, 0.77 (95% CI, 0.68-0.79) in patients with baseline cardiovascular disease, and 0.71 (95% CI, 0.56-0.90) in patients without baseline cardiovascular disease compared with HRs for sulfonylurea-treated patients. Sitagliptin and linagliptin showed statistically lower risk for hospitalization for HF (HR, 0.76; 95% CI, 0.67-0.86 for sitagliptin-prescribed patients; HR, 0.74; 95% CI, 0.59-0.92 for linagliptin-prescribed patients) than for sulfonylurea. The HRs for hospitalization for myocardial infarction and stroke with the use of a DPP-4i versus sulfonylurea were HR, 0.76 (95% CI, 0.67-0.87) and HR, 0.63 (95% CI, 0.60-0.67), respectively.

CONCLUSIONS

Our findings suggest that DPP-4i use did not increase the risk of HF compared with sulfonylurea. In addition, the risks for cardiovascular outcomes were not elevated in DPP-4i-treated patients compared with sulfonylurea-treated patients.

Metformin to Augment Strength Training Effective Response in Seniors (MASTERS): study protocol for a randomized controlled trial

BACKGROUND

Muscle mass and strength are strong determinants of a person's quality of life and functional independence with advancing age. While resistance training is the most effective intervention to combat age-associated muscle atrophy (sarcopenia), the ability of older adults to increase muscle mass and strength in response to training is blunted and highly variable. Thus, finding novel ways to complement resistance training to improve muscle response and ultimately quality of life among older individuals is critical. The purpose of this study is to determine whether a commonly prescribed medication called metformin can be repurposed to improve the response to resistance exercise training by altering the muscle tissue inflammatory environment.

METHODS/DESIGN

Individuals aged 65 and older are participating in a two-site, randomized, double-blind, placebo-controlled trial testing the effects of metformin or placebo on muscle size, strength, and physical function when combined with a progressive resistance training program. Participants consume 1700 mg of metformin per day or placebo for 2 weeks before engaging in a 14-week progressive resistance training regimen, with continued metformin or placebo. Participants are then monitored post-training to determine if the group taking metformin derived greater overall benefit from training in terms of muscle mass and strength gains than those on placebo. Muscle biopsies are taken from the vastus lateralis at three time points to assess individual cellular and molecular adaptations to resistance training and also changes in response to metformin.

DISCUSSION

The response of aged muscles to a resistance training program does not always result in a positive outcome; some individuals even experience a loss in muscle mass following resistance training. Thus, adjuvant therapies, including pharmacological ones, are required to optimize response to training in those who do not respond and may be at increased risk of frailty. This is the first known metformin repurposing trial in non-diseased individuals, aimed specifically at the resistance exercise "non-responder" phenotype present in the aging population. The overall goal of this trial is to determine if combined exercise-metformin intervention therapy will benefit older individuals by promoting muscle hypertrophy and strength gains, thereby maintaining functional independence.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02308228 . Registered on 25 November 2014.

Efficacy and safety of sitagliptin/metformin fixed-dose combination compared with glimepiride in patients with type 2 diabetes: A multicenter randomized double-blind study

BACKGROUND

Early initiation of combination therapy using antihyperglycemic agents is recommended for treating type 2 diabetes (T2D). The present multicenter double-blind randomized parallel-group study examined the efficacy and safety of a sitagliptin and metformin fixed-dose combination (Sita/Met) compared with glimepiride in T2D patients as initial treatment.

METHODS

Type 2 diabetes patients (aged ≥18 years) were randomized to Sita/Met or glimepiride for 30 weeks after a wash-off run-in period. The primary endpoint was change from baseline (CFB) in HbA1c. Secondary endpoints included the proportion of patients achieving target goal (HbA1c < 7.0 % [53 mmol/mol]) and CFB in fasting plasma glucose (FPG). Safety assessments comprised weight gain from baseline and the incidence of adverse events (AEs).

RESULTS

In total, 292 patients were randomized to Sita/Met (n = 147) or glimepiride (n = 145). After 30 weeks, Sita/Met demonstrated superiority over glimepiride in reducing HbA1c (-1.49 % vs -0.71 %, respectively; between-group difference - 0.78 %; P < 0.001). A significantly higher proportion of patients achieved the target goal with Sita/Met (81.2 %) than with glimepiride (40.1 %; P < 0.001). Greater reduction in FPG occurred with Sita/Met than with glimepiride (least-squares mean difference - 23.5 mg/dL; P < 0.001). Both drugs were generally well tolerated. Hypoglycemia events and weight gain were significantly lower in patients with Sita/Met than with glimepiride (5.5 % vs 20.1 % and -0.83 vs +0.90 kg, respectively; both P < 0.001). No serious drug-related AEs or deaths were reported.

CONCLUSIONS

Compared with glimepiride, Sita/Met as an initial treatment led to significantly greater improvements in glycemic control and body weight changes, with a lower incidence of hypoglycemia, over 30 weeks.

Understanding and overcoming metformin gastrointestinal intolerance

Metformin is the most widely prescribed drug for patients with type 2 diabetes mellitus and the first-line pharmacological option as supported by multiple international guidelines, yet a rather large proportion of patients cannot tolerate metformin in adequate amounts because of its associated gastrointestinal (GI) adverse events (AEs). GI AEs typically encountered with metformin therapy include diarrhoea, nausea, flatulence, indigestion, vomiting and abdominal discomfort, with diarrhoea and nausea being the most common. Although starting at a low dose and titrating slowly may help prevent some GI AEs associated with metformin, some patients are unable to tolerate metformin at all and it may also be difficult to convince patients to start metformin again after a bout of GI AEs. Despite this clinical importance, the underlying mechanisms of the GI intolerance associated with metformin are poorly known. In the present review, we discuss: the epidemiology of metformin-associated GI intolerance and its underlying mechanisms; genotype variability and associated factors affecting metformin GI intolerance, such as comorbidities, co-medications and bariatric surgery; clinical consequences and therapeutic strategies to overcome metformin GI intolerance. These strategies include appropriate titration of immediate-release metformin, use of extended-release metformin, the promise of delayed-release metformin and gut microbiome modulators, as well as alternative pharmacological therapies when metformin cannot be tolerated at all. Given the available data, all efforts should be made to maintain metformin before considering a shift to another drug therapy.

Clinical Outcomes of Metformin Use in Populations With Chronic Kidney Disease, Congestive Heart Failure, or Chronic Liver Disease: A Systematic Review

BACKGROUND

Recent changes to the U.S. Food and Drug Administration boxed warning for metformin will increase its use in persons with historical contraindications or precautions. Prescribers must understand the clinical outcomes of metformin use in these populations.

PURPOSE

To synthesize data addressing outcomes of metformin use in populations with type 2 diabetes and moderate to severe chronic kidney disease (CKD), congestive heart failure (CHF), or chronic liver disease (CLD) with hepatic impairment.

DATA SOURCES

MEDLINE (via PubMed) from January 1994 to September 2016, and Cochrane Library, EMBASE, and International Pharmaceutical Abstracts from January 1994 to November 2015.

STUDY SELECTION

English-language studies that: 1) examined adults with type 2 diabetes and CKD (with estimated glomerular filtration rate less than 60 mL/min/1.73 m2), CHF, or CLD with hepatic impairment; 2) compared diabetes regimens that included metformin with those that did not; and 3) reported all-cause mortality, major adverse cardiovascular events, and other outcomes of interest.

DATA EXTRACTION

2 reviewers abstracted data and independently rated study quality and strength of evidence.

DATA SYNTHESIS

On the basis of quantitative and qualitative syntheses involving 17 observational studies, metformin use is associated with reduced all-cause mortality in patients with CKD, CHF, or CLD with hepatic impairment, and with fewer heart failure readmissions in patients with CKD or CHF.

LIMITATIONS

Strength of evidence was low, and data on multiple outcomes of interest were sparse. Available studies were observational and varied in follow-up duration.

CONCLUSION

Metformin use in patients with moderate CKD, CHF, or CLD with hepatic impairment is associated with improvements in key clinical outcomes. Our findings support the recent changes in metformin labeling.

PRIMARY FUNDING SOURCE

U.S. Department of Veterans Affairs. (PROSPERO: CRD42016027708).

Vascular KATP channels mitigate severe muscle O2 delivery-utilization mismatch during contractions in chronic heart failure rats

The vascular ATP-sensitive K⁺ (K_ATP) channel is a mediator of skeletal muscle microvascular oxygenation (PO₂mv) during contractions in health. We tested the hypothesis that K_ATP channel function is preserved in chronic heart failure (CHF) and therefore its inhibition would reduce PO₂mv and exacerbate the time taken to reach the PO₂mv steady-state during contractions of the spinotrapezius muscle. Moreover, we hypothesized that subsequent K_ATP channel activation would oppose the effects of this inhibition. Muscle PO₂mv (phosphorescence quenching) was measured during 180s of 1-Hz twitch contractions (∼6V) under control, glibenclamide (GLI, K_ATP channel antagonist; 5mg/kg) and pinacidil (PIN, K_ATP channel agonist; 5mg/kg) conditions in 16 male Sprague-Dawley rats with CHF induced via myocardial infarction (coronary artery ligation, left ventricular end-diastolic pressure: 18±1mmHg). GLI reduced baseline PO₂mv (control: 28.3±0.9, GLI: 24.8±1.0mmHg, p<0.05), lowered mean PO₂mv (average PO₂mv during the overall time taken to reach the steady-state; control: 20.6±0.6, GLI: 17.6±0.3mmHg, p<0.05), and slowed the attainment of steady-state PO₂mv (overall mean response time; control: 66.1±10.2, GLI: 93.6±7.8s, p<0.05). PIN opposed these effects on the baseline PO₂mv, mean PO₂mv and time to reach the steady-state PO₂mv (p<0.05 for all vs. GLI). Inhibition of K_ATP channels exacerbates the transient mismatch between muscle O₂ delivery and utilization in CHF rats and this effect is opposed by PIN. These data reveal that the K_ATP channel constitutes one of the select few well-preserved mechanisms of skeletal muscle microvascular oxygenation control in CHF.

Update on the treatment of type 2 diabetes mellitus

To achieve good metabolic control in diabetes and keep long term, a combination of changes in lifestyle and pharmacological treatment is necessary. Achieving near-normal glycated hemoglobin significantly, decreases risk of macrovascular and microvascular complications. At present there are different treatments, both oral and injectable, available for the treatment of type 2 diabetes mellitus (T2DM). Treatment algorithms designed to reduce the development or progression of the complications of diabetes emphasizes the need for good glycaemic control. The aim of this review is to perform an update on the benefits and limitations of different drugs, both current and future, for the treatment of T2DM. Initial intervention should focus on lifestyle changes. Moreover, changes in lifestyle have proven to be beneficial, but for many patients is a complication keep long term. Physicians should be familiar with the different types of existing drugs for the treatment of diabetes and select the most effective, safe and better tolerated by patients. Metformin remains the first choice of treatment for most patients. Other alternative or second-line treatment options should be individualized depending on the characteristics of each patient. This article reviews the treatments available for patients with T2DM, with an emphasis on agents introduced within the last decade.

Extracellular microRNAs and endothelial hyperglycaemic memory: a therapeutic opportunity?

Type 2 diabetes mellitus (T2DM) is a major cause of cardiovascular (CV) disease. Several large clinical trials have shown that the risk for patients with diabetes of developing CV complications is only partially reduced by early, intensive glycaemic control and lifestyle interventions, and that such complications result from changes in complex, not fully explored networks that contribute to the maintenance of endothelial function. The accumulation of senescent cells and the low-grade, systemic, inflammatory status that accompanies aging (inflammaging) are involved in the development of endothelial dysfunction. Such phenomena are modulated by epigenetic mechanisms, including microRNAs (miRNAs). MiRNAs can modulate virtually all gene transcripts. They can be secreted by living cells and taken up in active form by recipient cells, providing a new communication tool between tissues and organs. MiRNA deregulation has been associated with the development and progression of a number of age-related diseases, including the enduring gene expression changes seen in patients with diabetes. We review recent evidence on miRNA changes in T2DM, focusing on the ability of diabetes-associated miRNAs to modulate endothelial function, inflammaging and cellular senescence. We also discuss the hypothesis that miRNA-containing extracellular vesicles (i.e. exosomes and microvesicles) could be harnessed to restore a 'physiological' signature capable of preventing or delaying the harmful systemic effects of T2DM.

Effectiveness of sulphonylureas in the therapy of diabetes mellitus type 2 patients: an observational cohort study

BACKGROUND

We compared all-cause mortality, major macrovascular events (MACE) and diabetes-related hospitalizations in T2DM-incident patients newly treated with metformin (MET) versus sulphonylureas (SU) monotherapy and in T2DM-prevalent patients newly treated with MET+SU versus MET+DPP4-inhibitor combination therapy.

METHODS

We analysed anonymized data obtained from a German health fund. Patients were included when they had started MET versus SU therapy or MET+SU versus MET+DPP4 therapy between 01/07/2010 and 31/12/2011. Observation started with the first MET/SU prescription or the first prescription of the second agent of a MET+SU/MET+DPP4 combination therapy. Follow-up time lasted until the end of data availability (a minimum of 12 months), death or therapy discontinuation.

RESULTS

In total, 434,291 T2DM-prevalent and 35,661 T2DM-incident patients were identified. Of the identified T2DM-incident patients, 904/7,874 started SU/MET monotherapy, respectively, with a mean age of 70.1/61.4 years (54.6/50.3 % female; Charlson Comorbidity Index (CCI) 1.4/2.2; 933/7,350 observed SU/MET patient years). 4,157/1,793 SU+MET/DPP4+MET therapy starters had a mean age of 68.1/62.2 years (53.4/50.8 % female; CCI 2.8/2.6; 4,556/1,752 observed SU+MET/ DPP4+MET patient years). In a propensity score matched (PSM) comparison, the HRs (95 % CIs) associated with SU monotherapy compared to MET monotherapy exposure were 1.4 (0.9-2.3) for mortality, 1.4 (0.9-2.2) for MACE, 4.1 (1.5-10.9) for T2DM hospitalizations and 1.6 (1.2-2.3) for composite event risk. In a multivariable Cox regression model, SU monotherapy was associated with higher mortality (aHR 2.0; 1.5-2.6), higher MACE (aHR 1.3; 1.0-1.7) and higher T2DM hospitalizations (aHR 2.8; 1.8-4.4), which corresponded with a higher composite event risk (aHR 1.8; 1.5-2.1). No significant differences in event rates were observed in the PSM comparison between DPP4+MET/SU+MET combination therapy starters and in the multivariable Cox regression analysis.

CONCLUSIONS

Our results show that SU monotherapy may be associated with increased mortality, MACE and T2DM hospitalizations, compared to MET monotherapy. When considering SU therapy, the associated cardiovascular risk should also be taken into account.

Sulphonylurea compared to DPP-4 inhibitors in combination with metformin carries increased risk of severe hypoglycemia, cardiovascular events, and all-cause mortality

AIMS

There are safety concerns related to sulphonylurea treatment. The objective of this nationwide study was to compare the risk of cardiovascular disease (CVD), all-cause mortality and severe hypoglycemia in patients with type 2 diabetes (T2D) starting second-line treatment with either metformin+sulphonylurea or metformin+dipeptidyl peptidase-4 inhibitor (DPP-4i).

METHODS

All patients with T2D in Sweden who initiated second-line treatment with metformin+sulphonylurea or metformin+DPP-4i during 2006-2013 (n=40,736 and 12,024, respectively) were identified in this nationwide study. The Swedish Prescribed Drug Register and the Cause of Death and National Patient Registers were used, and Cox survival models adjusted for age, sex, fragility, prior CVD, and CVD-preventing drugs were applied to estimate risks of events. Propensity score adjustments and matching methods were used to test the results.

RESULTS

Of 52,760 patients; 77% started metformin+SU and 23% metformin+DPP-4i. Crude incidences for severe hypoglycemia, CVD, and all-cause mortality in the SU cohort were 2.0, 19.6, and 24.6 per 1000 patient-years and in the DPP-4i cohort were 0.8, 7.6, and 14.9 per 1000 patient-years, respectively. Sulphonylurea compared with DPP4i was associated with higher risk of subsequent severe hypoglycemia, fatal and nonfatal CVD, and all-cause mortality; adjusted HR (95% CI): 2.07 (1.11-3.86); 1.17 (1.01-1.37); and 1.25 (1.02-1.54), respectively. Results were confirmed by additional propensity-adjusted and matched analyses. Among the SU drugs, glibenclamide had the highest risks.

CONCLUSIONS

Metformin+SU treatment was associated with an increased risk of subsequent severe hypoglycemia, cardiovascular events, and all-cause mortality compared with metformin+DPP4i. Results from randomized trials will be important to elucidate causal relationships.

Association Between Hospitalization for Heart Failure and Dipeptidyl Peptidase 4 Inhibitors in Patients With Type 2 Diabetes: An Observational Study

OBJECTIVE

To examine, among patients with type 2 diabetes, the association between hospitalization for heart failure (hHF) and treatment with dipeptidyl peptidase 4 inhibitors (DPP-4is) versus sulfonylureas (SUs), and treatment with saxagliptin versus sitagliptin.

RESEARCH DESIGN AND METHODS

This was a retrospective, observational study using a U.S. insurance claims database. Patients initiated treatment between 1 August 2010 and 30 August 2013, and had no use of the comparator treatments in the prior 12 months (baseline). Each comparison consisted of patients matched 1:1 on a propensity score. Time to each outcome was compared between matched groups using Cox models. Analyses were stratified by the presence of baseline cardiovascular disease (CVD). Secondary analyses examined associations between comparator treatments and other selected cardiovascular events.

RESULTS

After matching, the study included 218,556 patients in comparisons of DPP-4i and SU, and 112,888 in comparisons of saxagliptin and sitagliptin. The hazard ratios (HRs) of hHF were as follows: DPP-4i versus SU (reference): HR 0.95 (95% CI 0.78-1.15), P = 0.580 for patients with baseline CVD; HR 0.59 (95% CI 0.38-0.89), P = 0.013 for patients without baseline CVD; saxagliptin versus sitagliptin (reference): HR 0.95 (95% CI 0.70-1.28), P = 0.712 for patients with baseline CVD; HR 0.99 (95% CI 0.56-1.75), P = 0.972 for patients without baseline CVD. Comparisons of the individual secondary and composite cardiovascular outcomes followed a similar pattern.

CONCLUSIONS

In patients with type 2 diabetes, there was no association between hHF, or other selected cardiovascular outcomes, and treatment with a DPP-4i relative to SU or treatment with saxagliptin relative to sitagliptin.

DPP-4 inhibitors and cardiovascular disease in type 2 diabetes mellitus. Expectations, observations and perspectives

AIMS

Cardiovascular disease (CVD) is the greatest burden of type 2 diabetes mellitus (T2DM) in terms of morbility, mortality and costs for individuals and societies. Therefore, its prevention is a major goal in diabetes care. Optimal treatment of hyperglycemia is certainly instrumental to CVD prevention. Optimal treatment means both establishing the most appropriate glycemic target for the given individual and selecting the medication(s) with the most favourable benefit/safety ratio. CVD safety, if not a clear CVD benefit, is certainly required for all antidiabetic agents. Dipeptidyl-peptidase-4 (DPP-4) inhibitors are among the classes of antidiabetic agents most recently made available for diabetes care. A major question to be addressed is the effect of these compounds on CVD. Expectations were high for their mechanism of action, which targets also post-prandial glucose and minimize hypoglycemia risk, thereby providing a sort of global glucose control, and for some potentially beneficial extra-glycemic effects. This article reviews the existing literature on this issue.

DATA SYNTHESIS

Data published so far document that DPP-4 inhibitors have a wide spectrum of glycemic and extra-glycemic effects potentially reducing the risk of CVD as well as favourable effects on intermediate or surrogate CVD endpoints. These data heralded a better CVD outcome. Accordingly, pooling CVD safety data from phase 3 and 4 studies conducted with DPP-4 inhibitors suggested that their use might translate into a better CVD outcome. Data from three CVD outcome RCTs with alogliptin, saxagliptin and sitagliptin documented no harm but did not show any benefit on major CVD events. A modest but significant increased risk of hospitalization for heart failure was observed with saxagliptin and with alogliptin (only in subjects with no history of heart failure before randomization) but not with sitagliptin. A study currently in progress with linagliptin will provide further insights in the issue of CVD safety and benefit.

CONCLUSIONS

It should be considered that most alternative oral antidiabetic agents generally do not possess a better CVD risk profile than DPP-4 inhibitors and that some of them, indeed, should be used with caution because of potentially adverse effects on heart and vasculature. Overall, the selection of antidiabetic agent(s) with the most favourable CVD profile is mandatory but still challenging in diabetes care.

Comparative review of dipeptidyl peptidase-4 inhibitors and sulphonylureas

Type 2 diabetes (T2DM) is a progressive disease, and pharmacotherapy with a single agent does not generally provide durable glycaemic control over the long term. Sulphonylurea (SU) drugs have a history stretching back over 60 years, and have traditionally been the mainstay choice as second-line agents to be added to metformin once glycaemic control with metformin monotherapy deteriorates; however, they are associated with undesirable side effects, including increased hypoglycaemia risk and weight gain. Dipeptidyl peptidase (DPP)-4 inhibitors are, by comparison, more recent, with the first compound being launched in 2006, but the class now globally encompasses at least 11 different compounds. DPP-4 inhibitors improve glycaemic control with similar efficacy to SUs, but do not usually provoke hypoglycaemia or weight gain, are relatively free from adverse side effects, and have recently been shown not to increase cardiovascular risk in large prospective safety trials. Because of these factors, DPP-4 inhibitors have become an established therapy for T2DM and are increasingly being positioned earlier in treatment algorithms. The present article reviews these two classes of oral antidiabetic drugs (DPP-4 inhibitors and SUs), highlighting differences and similarities between members of the same class, as well as discussing the potential advantages and disadvantages of the two drug classes. While both classes have their merits, the choice of which to use depends on the characteristics of each individual patient; however, for the majority of patients, DPP-4 inhibitors are now the preferred choice.

Metformin: A candidate for the treatment of gynecological tumors based on drug repositioning

Metformin is a first-line drug used for the treatment of type 2 diabetes. Recently, metformin has been reported to reduce the carcinogenic risk and inhibit tumor cell growth in glioma and breast cancer. The anticancer action of metformin involves the enhancement of phosphorylation of liver kinase B1, activation of adenosine monophosphate-activated protein kinase and inhibition of mammalian target of rapamycin, which reduces cell growth. Metformin is anticipated to exert antitumor effects in gynecological cancer, and its efficacy for the treatment of endometrial, breast and ovarian cancer has been suggested in preclinical studies and clinical trials. Although the effect of metformin on cervical cancer remains to be examined in clinical trials, its antitumor effects have been reported in preclinical studies. Thus, the use of metformin for the treatment of gynecological cancer may become a successful example of drug repositioning, following establishment of the drug's antitumor effects, risk evaluation, screening and validation of efficacy.

Impact of glucose-lowering drugs on cardiovascular disease in type 2 diabetes

Type 2 diabetes mellitus (T2DM) is characterized by multiple pathophysiologic abnormalities. With time, multiple glucose-lowering medications are commonly required to reduce and maintain plasma glucose concentrations within the normal range. Type 2 diabetes mellitus individuals also are at a very high risk for microvascular complications and the incidence of heart attack and stroke is increased two- to three-fold compared with non-diabetic individuals. Therefore, when selecting medications to normalize glucose levels in T2DM patients, it is important that the agent not aggravate, and ideally even improve, cardiovascular risk factors (CVRFs) and reduce cardiovascular morbidity and mortality. In this review, we examine the effect of oral (metformin, sulfonylureas, meglitinides, thiazolidinediones, DPP4 inhibitors, SGLT2 inhibitors, and α-glucosidase inhibitors) and injectable (glucagon-like peptide-1 receptor agonists and insulin) glucose-lowering drugs on established CVRFs and long-term studies of cardiovascular outcomes. Firm evidence that in T2DM cardiovascular disease can be reversed or prevented by improving glycaemic control is still incomplete and must await large, long-term clinical trials in patients at low risk using modern treatment strategies, i.e., drug combinations designed to maximize HbA1c reduction while minimizing hypoglycaemia and excessive weight gain.

Comparison of diabetes-associated secondary healthcare utilization between alternative oral antihyperglycaemic dual therapy combinations with metformin in patients with type 2 diabetes: an observational cohort study

AIMS

To compare diabetes-associated secondary healthcare utilization in patients with type 2 diabetes (T2DM) prescribed sulphonylureas (SUs) versus other oral antihyperglycaemic agents (OHAs) as an add-on to metformin monotherapy (metformin + SU vs metformin + OHA).

METHODS

This retrospective cohort study used data from the Clinical Practice Research Datalink linked to Hospital Episode Statistics. Adults with T2DM initiated on metformin + SU or metformin + OHA from April 2003 to March 2012 were identified. Patients were matched using propensity scores. Diabetes-associated secondary healthcare visits were counted from >6 months post-initiation of dual therapy until treatment change or end of follow-up. Outcomes were calculated as rate ratios, adjusted for over-dispersion using negative binomial regression and propensity score for covariates.

RESULTS

After propensity score matching, 1704 patients were included in each cohort. For the primary objective (diabetes-associated inpatient and outpatient visits combined), the metformin + SU cohort had a directionally higher rate of diabetes-associated secondary healthcare utilization than the metformin + OHA cohort [adjusted rate ratio 1.12, 95% confidence interval (CI) 0.97-1.29]. For the secondary outcomes, the adjusted rate ratio was 1.38 (95% CI 0.95-2.00) for inpatient admissions and 1.10 (95% CI 0.95-1.28) for outpatient visits. Macrovascular complications, accounting for 77.2% of inpatient admissions, occurred at a statistically significantly higher rate in the metformin + SU cohort than in the metformin + OHA cohort (adjusted rate ratio 1.77, 95% CI 1.15-2.71).

CONCLUSIONS

This study found a statistically significant higher rate of inpatient admissions for macrovascular complications and cardiology outpatient visits and, overall, a directionally higher rate of secondary healthcare utilization for patients prescribed metformin + SU than for those prescribed metformin + OHA. This adds to the evidence that long-term and health economic outcomes should be considered in treatment decisions for patients with type 2 diabetes.

Metformin utilisation in Australian community and aged care settings

OBJECTIVE

The objective of this study was to: (i) evaluate the potentially inappropriate prescribing (PIP; defined as the use of metformin in the presence of contraindications and/or use in excessive dosage based on the renal function) of metformin in people receiving medication reviews in Australia and (ii) identify the predictors for PIP of metformin.

METHOD

Retrospective study of patients taking metformin through a large medication review database, containing records between January 2010 and June 2012. Data, including demographics, medical conditions, medications and relevant pathology results, were extracted for analysis. Multivariate logistic regression analysis was used to detect risk factors for PIP of metformin.

RESULTS

Medication reviews pertaining to 6386 patients who received Home Medicines Reviews (HMRs, n=5327) or Residential Medication Management Reviews (RMMRs, n=1059) were included in this study. Overall, there were 12.9% (n=685) of patients in the HMR group and 17.4% (n=184) of patients in the RMMR group who had PIP of metformin. Multivariate logistic regression showed age, gender and type of medication review service as the significant (p<0.05) independent risk factors for PIP of metformin.

CONCLUSION

Metformin was often used in patients with contraindications, or in higher than recommended dosages in patients with renal impairment. Given the recent debate in the literature about the role of metformin in the presence of contraindications, a detailed prospective study in patients with contraindications and its association with lactic acidosis is warranted to establish the way in which metformin is to be used in these patients.

The combination of DPP-4 inhibitors versus sulfonylureas with metformin after failure of first-line treatment in the risk for major cardiovascular events and death

OBJECTIVE

To determine whether the combination of dipeptidyl-peptidase 4 (DPP-4) inhibitors vs. sulfonylureas with metformin after failure of first-line treatment is associated with a decreased risk for major adverse cardiovascular events (myocardial infarction and stroke) and for all-cause mortality.

METHOD

Using the UK Clinical Practice Research Datalink, a cohort of patients newly treated with metformin or sulfonylurea monotherapy between January 1, 1988, and December 31, 2011, was identified and was followed until December 31, 2012. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models to compare the DPP-4 inhibitor-metformin combination to the sulfonylurea-metformin combination so as to study the risk for a composite endpoint consisting of myocardial infarction, stroke and all-cause mortality. The models were adjusted for high-dimensional propensity score deciles.

RESULTS

The cohort consisted of 11,807 patients that included 2286 on a DPP-4 inhibitor-metformin combination and 9521 on a sulfonylurea-metformin combination. The crude incidence rates (95% CIs) of the composite endpoint were 1.2% (0.8% to 1.7%) and 2.2% (1.9% to 2.5%) per year for the DPP-4 inhibitor-metformin and sulfonylurea-metformin combinations, respectively. In the high-dimensional propensity score-adjusted model, the use of the DPP-4 inhibitor-metformin combination was associated with a 38% decreased risk for the composite endpoint (adjusted HR: 0.62; 95% CI 0.40 to 0.98), compared with the sulfonylurea-metformin combination.

CONCLUSIONS

The use of a DPP-4 inhibitor combination with metformin, compared with a sulfonylurea-metformin combination, was associated with decreased risks for major cardiovascular events and all-cause mortality.

Impact of cardiovascular complications among patients with Type 2 diabetes mellitus: a systematic review

Macrovascular and microvascular complications that accompany Type 2 diabetes mellitus (T2DM) add to the burden among patients. The purpose of this systematic review is to conduct a comprehensive search of the medical literature investigating the prevalence of cardiovascular (CV) complications and assess their impact on healthcare costs, quality of life and mortality among patients with T2DM in the context of microvascular complications. A total of 76 studies and reports were used in this systematic review. Hypertension was the most prevalent complication among patients with T2DM. The additional cost burden due to CV complications was higher than any other complication except end-stage renal disease. Quality of life was much lower among patients with CV complications and T2DM, and mortality was higher than either illness alone.

Metformin in patients with type 2 diabetes and kidney disease: a systematic review

IMPORTANCE

Metformin is widely viewed as the best initial pharmacological option to lower glucose concentrations in patients with type 2 diabetes mellitus. However, the drug is contraindicated in many individuals with impaired kidney function because of concerns of lactic acidosis.

OBJECTIVE

To assess the risk of lactic acidosis associated with metformin use in individuals with impaired kidney function.

EVIDENCE ACQUISITION

In July 2014, we searched the MEDLINE and Cochrane databases for English-language articles pertaining to metformin, kidney disease, and lactic acidosis in humans between 1950 and June 2014. We excluded reviews, letters, editorials, case reports, small case series, and manuscripts that did not directly pertain to the topic area or that met other exclusion criteria. Of an original 818 articles, 65 were included in this review, including pharmacokinetic/metabolic studies, large case series, retrospective studies, meta-analyses, and a clinical trial.

RESULTS

Although metformin is renally cleared, drug levels generally remain within the therapeutic range and lactate concentrations are not substantially increased when used in patients with mild to moderate chronic kidney disease (estimated glomerular filtration rates, 30-60 mL/min per 1.73 m2). The overall incidence of lactic acidosis in metformin users varies across studies from approximately 3 per 100,000 person-years to 10 per 100,000 person-years and is generally indistinguishable from the background rate in the overall population with diabetes. Data suggesting an increased risk of lactic acidosis in metformin-treated patients with chronic kidney disease are limited, and no randomized controlled trials have been conducted to test the safety of metformin in patients with significantly impaired kidney function. Population-based studies demonstrate that metformin may be prescribed counter to prevailing guidelines suggesting a renal risk in up to 1 in 4 patients with type 2 diabetes mellitus--use which, in most reports, has not been associated with increased rates of lactic acidosis. Observational studies suggest a potential benefit from metformin on macrovascular outcomes, even in patients with prevalent renal contraindications for its use.

CONCLUSIONS AND RELEVANCE

Available evidence supports cautious expansion of metformin use in patients with mild to moderate chronic kidney disease, as defined by estimated glomerular filtration rate, with appropriate dosage reductions and careful follow-up of kidney function.