Comparative safety and effectiveness of sitagliptin in patients with type 2 diabetes: retrospective population based cohort study

Biowaiver Monograph for Immediate-Release Solid Oral Dosage Forms: Sitagliptin Phosphate Monohydrate

Sitagliptin is an antihyperglycemic drug used in adults for the treatment of diabetes Type 2. Literature data and in-house experiments were applied in this monograph to assess whether methods based on the Biopharmaceutics Classification System (BCS) could be used to assess the bioequivalence of solid immediate-release (IR) oral dosage forms containing sitagliptin phosphate monohydrate, as an alternative to a pharmacokinetic study in human volunteers. The solubility and permeability characteristics of sitagliptin were reviewed according to the BCS, along with dissolution, therapeutic index, therapeutic applications, pharmacokinetics, pharmacodynamic characteristics, reports of bioequivalence (BE) / bioavailability problems, data on interactions between the drug and excipients and other data germane to the subject. All data reviewed in this monograph unambiguously support classification of sitagliptin as a BCS Class 1 drug. In light of its broad therapeutic index and lack of severe adverse effects, the clinical risks associated with moderately supraoptimal doses were deemed inconsequential, as were the risks associated with moderately suboptimal doses. Taking all evidence into consideration, it was concluded that the BCS-based biowaiver can be implemented for solid IR oral drug products containing sitagliptin phosphate monohydrate, provided (a) the test product is formulated solely with excipients commonly present in solid IR oral drug products approved in ICH or associated countries and used in amounts commonly applied in this type of product, (b) data in support of the BCS-based biowaiver are obtained using the methods recommended by the WHO, FDA, EMA or ICH and (c) the test product and the comparator product (which is the innovator product in this case) meet all in vitro dissolution specifications provided in the WHO, FDA, EMA or ICH guidance.

Costarting sitagliptin with metformin is associated with a lower likelihood of disease progression in newly treated people with type 2 diabetes: a cohort study

AIM

To examine whether early addition of sitagliptin to metformin is associated with a delay in type 2 diabetes progression.

METHODS

Administrative health records from Alberta, Canada, for the period April 2008 to March 2015, were used to conduct a retrospective cohort study in new metformin users. People who started sitagliptin on the same day they initiated metformin therapy were compared with those who added sitagliptin later. Insulin initiation served as a surrogate marker for diabetes progression, and multivariable logistic regression models were used to evaluate the association with sitagliptin addition (costart vs later use). A mixed-effects linear regression model was used to examine the effect of timing of sitagliptin addition on HbA_1c change over 1 year.

RESULTS

The mean (sd) age of the 8764 people who used sitagliptin was 52.1 (11.1) years, 5665 (64.6%) were men, and 1153 (13.2%) started sitagliptin on the same day as metformin. Insulin was added to the therapy of 173 (15.0%) costarters and 1453 (19.1%) later sitagliptin users. The adjusted odds ratio for adding insulin was 0.76 (95% CI 0.64 to 0.90) in favour of costarting sitagliptin. HbA_1c levels decreased in both groups 1 year after starting sitagliptin, with costarters having a significantly greater reduction [absolute between-group difference of 0.5% (95% CI 0.3 to 0.7)] compared with later sitagliptin users.

CONCLUSION

Costarting drug therapy with sitagliptin and metformin was associated with a lower likelihood of disease progression in people with type 2 diabetes compared with adding sitagliptin later.

PERsistent Sitagliptin treatment & Outcomes (PERS&O 2.0) study, long-term results: a real-world observation on DPP4-inhibitor effectiveness

INTRODUCTION

Sitagliptin is a dipeptidyl peptidase 4 inhibitor for the treatment of type 2 diabetes (T2D). Limited real-world data on its effectiveness and safety are available from an Italian population.

RESEARCH DESIGN AND METHODS

We evaluated long-term clinical data from the single-arm PERsistent Sitagliptin Treatment & Outcomes (PERS&O) study, which collected information on 440 patients with TD2 (275 men, 165 women; mean age 64.1 years; disease median duration: 12 years) treated with sitagliptin 'add-on'. For each patient, we estimated the 10-year cardiovascular (CV) risk using the UK Prospective Diabetes Study (UKPDS) Risk Engine (RE). Drug survival was evaluated using Kaplan-Meier survival curves; repeated measures mixed effects models were used to evaluate the evolution of glycated hemoglobin (HbA1c) and CV risk during sitagliptin treatment.

RESULTS

At baseline, most patients were overweight or obese (median body mass index (BMI) (kg/m²) 30.2); median HbA1c was 8.4%; median fasting plasma glucose: 172 mg/dL; median UKPDS RE score: 24.8%, being higher in men (median 30.2%) than in women (median 17.0%) as expected. Median follow-up from starting sitagliptin treatment was 5.6 years. From Kaplan-Meier curves, the estimated median drug survival was 32.8 months when considering discontinuation for any cause and 58.4 months when considering discontinuation for loss of efficacy. A significant improvement in HbA1c was evident during treatment with sitagliptin (p<0.01): the reduction was rapid (median HbA1c after 4-6 months: 7.5%) and continued at longer follow-up. When comparing patients treated with sitagliptin versus those stopping sitagliptin and switching to another antihyperglycemic drug, we detected a significant difference in the evolution of HbA1c in favor of patients who continued sitagliptin treatment. The UKPDS RE score at 10 years and the BMI significantly improved during treatment with sitagliptin (p<0.001). Adverse events were relatively uncommon.

CONCLUSION

Patients with T2D treated with sitagliptin achieved an improvement in metabolic control and a reduction in CV risk and did not experience relevant adverse events.

Dipeptidyl peptidase-4 inhibitors as new tools for cardioprotection

Previous studies have demonstrated that individuals with type 2 diabetes mellitus (T2DM) have a two- to fourfold propensity to develop cardiovascular disease (CVD) than nondiabetic population, making CVD a major cause of death and disability among people with T2DM. The present treatment options for management of diabetes propose the earlier and more frequent use of new antidiabetic drugs that could control hyperglycaemia and reduce the risk of cardiovascular events. Findings from basic and clinical studies pointed out DPP-4 inhibitors as potentially novel pharmacological tools for cardioprotection. There is a growing body of evidence suggesting that these drugs have ability to protect the heart against acute ischaemia-reperfusion injury as well as reduce the size of infarction. Consequently, the prevention of degradation of the incretin hormones by the use of DPP-4 inhibitors represents a new strategy in the treatment of patients with T2DM and reduction of CV events in these patients. Here, we discuss the cardioprotective effects of DPP-4 inhibitors as well as proposed pathways that these hypoglycaemic agents target in the cardiovascular system.

Acute pancreatitis risk in type 2 diabetes patients treated with canagliflozin versus other antihyperglycemic agents: an observational claims database study

Objective: Observational evidence suggests that patients with type 2 diabetes mellitus (T2DM) are at increased risk for acute pancreatitis (AP) versus those without T2DM. A small number of AP events were reported in clinical trials of the sodium glucose co-transporter 2 inhibitor canagliflozin, though no imbalances were observed between treatment groups. This observational study evaluated risk of AP among new users of canagliflozin compared with new users of six classes of other antihyperglycemic agents (AHAs).Methods: Three US claims databases were analyzed based on a prespecified protocol approved by the European Medicines Agency. Propensity score adjustment controlled for imbalances in baseline covariates. Cox regression models estimated the hazard ratio of AP with canagliflozin compared with other AHAs using on-treatment (primary) and intent-to-treat approaches. Sensitivity analyses assessed robustness of findings.Results: Across the three databases, there were between 12,023-80,986 new users of canagliflozin; the unadjusted incidence rates of AP (per 1000 person-years) were between 1.5-2.2 for canagliflozin and 1.1-6.6 for other AHAs. The risk of AP was generally similar for new users of canagliflozin compared with new users of glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, sulfonylureas, thiazolidinediones, insulin, and other AHAs, with no consistent between-treatment differences observed across databases. Intent-to-treat and sensitivity analysis findings were qualitatively consistent with on-treatment findings.Conclusions: In this large observational study, incidence rates of AP in patients with T2DM treated with canagliflozin or other AHAs were generally similar, with no evidence suggesting that canagliflozin is associated with increased risk of AP compared with other AHAs.

Drug price, dosage and safety: Real-world evidence of oral hypoglycemic agents

OBJECTIVES

Drug price reduction is one of the major policies to restrain pharmaceutical expenses worldwide. This study explores whether there is a relationship between drug price and clinical quality using real-world data.

METHODS

Patients with newly-diagnosed type 2 diabetes receiving metformin or sulfonylureas during 2001 and 2010 were identified using the claim database of the Taiwan universal health insurance system. Propensity score matching was performed to obtain comparable subjects for analysis. Pharmaceutical products were categorized as brand-name agents (BD), highpriced generics (HP) or low-priced generics (LP). Indicators of clinical quality were defined as the dosage of cumulative oral hypoglycemic agents (OHA), exposure to other pharmacological classes of OHA, hospitalization or urgent visit for hypoglycemia or hyperglycemia, insulin utilization and diagnosis of diabetic complications within 1 year after diagnosis.

RESULTS

A total of 40,152 study subjects were identified. A generalized linear mix model showed that HP and BD users received similar OHA dosages with comparable clinical outcomes. By contrast, LP users had similar outcomes to BD users but received a 39% greater OHA dosage. A marginally higher risk of poor glycemic control in LP users was also observed.

CONCLUSIONS

Drug price is related to indicators of clinical quality. Clinicians and health authorities should monitor the utilization, effectiveness and clinical safety indicators of generic drugs, especially those with remarkably low prices.

The Association of Joint Pain and Dipeptidyl Peptidase-4 Inhibitor Use Among U.S. Adults With Type-2 Diabetes Mellitus

The purpose of this study was to examine the association of dipeptidyl peptidase-4 inhibitors (DPP4Is) with joint pain in adults with type 2 diabetes mellitus (T2DM). This was a retrospective cross-sectional study design, pooling data from the 2012 and 2014 Medical Expenditure Panel Survey. The sample consisted of 4,559 T2DM patients older than 40 years with (n = 3,224) or without joint pain (n = 1,335). Chi-square test and logistic regression were used to describe association of DPP4I use with joint pain. Among adults with T2DM, 70.7% reported physician-diagnosed joint pain. There were no significant differences in DPP4I use among those with and without joint pain (7.8% vs 6.3%). Even after adjusting for other factors that may affect DPP4I use, there was not a statistically significant difference in DPP4I use among adults with T2DM with and without joint pain (AOR = 1.04; 95% CI, 0.74-1.48). Adults with public health insurance (AOR = 1.76; 95% CI, 1.01-3.04), with prescription insurance (AOR = 1.76; 95% CI, 1.02-3.03), and with a heart disease (AOR = 1.59; 95% CI, 1.18-2.15). DPP4I use was not affected by the presence of joint pain.

Comparative Safety of Dipeptidyl Peptidase-4 Inhibitors Versus Sulfonylureas and Other Glucose-lowering Therapies for Three Acute Outcomes

Although the glucose lowering effect of dipeptidyl peptidase-4 (DPP4) inhibitors is well established, several potential serious acute safety concerns have been raised including acute kidney injury, respiratory tract infections, and acute pancreatitis. Using the UK-based Clinical Practice Research Datalink (CPRD), we identified initiators (365-day washout period) of DPP4 inhibitors and relevant comparators including initiators of sulfonylureas, metformin, thiazolidinediones, and insulin between January 2007 and January 2016 to quantify the association between DPP4 inhibitors and three acute health events – acute kidney injury, respiratory tract infections, and acute pancreatitis. The associations between drug and study outcomes were estimated using Cox proportional hazard models adjusted for deciles of high-dimensional propensity scores and number of additional glucose lowering agents. After controlling for potential confounders, the risk was not significantly increased or decreased for initiators of DPP4 inhibitors compared to sulfonylureas (hazard ratio (HR) [95% confidence interval (CI)] for acute kidney injury: 0.81 [0.56–1.18]; HR for respiratory tract infections: 0.93 [0.84–1.04]; HR for acute pancreatitis 1.03 [0.42–2.52], metformin (HR for respiratory tract infection 0.91 [0.65–1.27]), thiazolidinediones (HR for acute kidney injury: 1.12 [0.60–2.10]; HR for respiratory tract infections: 1.02 [0.86–1.21]; HR for acute pancreatitis: 1.21 [0.25–5.72]), or insulin (HR for acute kidney injury: 1.40 [0.77–2.55]; HR for respiratory tract infections: 0.74 [0.60–0.92]; HR for acute pancreatitis: 1.01 [0.24–4.19]). Initiators of DPP4 inhibitors were associated with an increased risk of acute kidney injury when compared to metformin initiators (HR [95% CI] for acute kidney injury: 1.85 [1.10–3.12], although this association was attenuated when DPP4 inhibitor monotherapy was compared to metformin monotherapy exposure as a time-dependent variable (HR 1.39 [0.91–2.11]). Initiation of a DPP4 inhibitor was not associated with an increased risk of acute kidney injury, respiratory tract infections, or acute pancreatitis compared to sulfonylureas or other glucose-lowering therapies.

Traditional Chinese Medical Care and Incidence of Stroke in Elderly Patients Treated with Antidiabetic Medications

Objectives: Experimental research has shown that herbal and traditional Chinese medicines (TCM) may serve as complements to Western medicine treatments in the control of blood glucose and cardiovascular complications, but population-based studies are limited. We investigated the association between TCM use and subsequent risk of stroke in older patients with diabetes. Study design: The database used in this cohort study contained longitudinal medical claims for one million subjects randomly selected among beneficiaries of a universal health care program in Taiwan. We identified a cohort of patients with diabetes aged 65 years and older who initiated anti-diabetic medications from 2000 to 2012. Patients who had at least two TCM outpatient visits after their initiation of anti-diabetic medications were considered TCM users. Main outcome measures: The incidence of stroke was measured until 2013. Cox regression models with TCM use as a time-dependent variable were used to calculate the adjusted hazard ratios (HRs) comparing TCM use with no use. Results: Over the 13-year period, 17,015 patients were identified; 4912 (28.9%) of them were TCM users. The incidence of stroke during the follow-up (per 1000 person-years) was 22.8 in TCM users and 25.7 in non-users. TCM users had an adjusted HR of 0.93 for the incidence of ischemic stroke (95% confidence interval [CI] 0.83, 1.04) and of 0.89 for developing hemorrhagic stroke (95% CI 0.66, 1.19), compared with non-users. Conclusions: In this study, in older patients receiving Western medicine treatments for diabetes, TCM use was not associated with an increased risk of developing ischemic stroke and hemorrhagic stroke.

Comparative Cardiovascular Risks of Dipeptidyl Peptidase-4 Inhibitors: Analyses of Real-world Data in Korea

Background and Objectives

To compare cardiovascular disease (CVD) risk associated with 5 different dipeptidyl peptidase-4 inhibitors (DPP-4is) in people with type 2 diabetes.

Methods

We identified 534,327 people who were newly prescribed sitagliptin (n=167,157), vildagliptin (n=67,412), saxagliptin (n=29,479), linagliptin (n=220,672), or gemigliptin (n=49,607) between January 2013 and June 2015 using the claims database of the Korean National Health Insurance System. A Cox proportional hazards model was used to estimate hazard ratios (HRs) for major CVD events (myocardial infarction, stroke, or death) among users of different DPP-4is. The model was adjusted for sex, age, duration of DPP-4i use, use of other glucose-lowering drugs, use of antiplatelet agents, hypertension, dyslipidemia, atrial fibrillation, chronic kidney disease, microvascular complications of diabetes, Charlson comorbidity index, and the calendar index year as potential confounders.

Results

Compared to sitagliptin users, the fully adjusted HRs for CVD events were 0.97 (95% confidence interval [CI], 0.94–1.01; p=0.163) for vildagliptin, 0.76 (95% CI, 0.71–0.81; p<0.001) for saxagliptin, 0.95 (95% CI, 0.92–0.98; p<0.001) for linagliptin, and 0.84 (95% CI, 0.80–0.88; p<0.001) for gemigliptin.

Conclusions

Compared to sitagliptin therapy, saxagliptin, linagliptin, and gemigliptin therapies were all associated with a lower risk of cardiovascular events.

Association between dipeptidyl peptidase-4 inhibitor drugs and risk of acute pancreatitis: A meta-analysis

BACKGROUND

Previous studies have reported conflicting results for the relationship between dipeptidyl peptidase-4 (DPP-4) inhibitor drugs and acute pancreatitis. The aim of this study was to investigate the association between DPP-4 inhibitors and an increased risk of acute pancreatitis using meta-analysis.

METHODS

We conducted a comprehensive search in PubMed, Embase, Web of Science, and Cochrane library from inception to March 4, 2017. Original articles with data on DPP-4 inhibitors and acute pancreatitis were included. We used random-effects models or fixed-effects models to combine the relative risks (RRs), odds ratio (OR), and hazard ratio (HRs) with 95% confidence intervals (CIs) in randomized controlled studies, case-control study and cohort study, respectively.

RESULTS

Five case-control studies, 5 randomized controlled studies, and 3 cohort studies were selected of the 451 retrieved abstracts. A higher risk of acute pancreatitis was observed with the following RR/OR and 95%CI: RR 1.67 (1.08-2.59) in randomized controlled studies and OR 1.45 (1.30-1.61) in case-control studies. However, the pooled HR of the 3 cohort studies failed to confirm this association.

CONCLUSION

There is a marginally higher risk of acute pancreatitis with DPP-4 inhibitors. However, this risk was not observed in cohort studies. Thus, further clinical trials are required to confirm this finding.

Cardiovascular safety outcomes of new antidiabetic therapies

PURPOSE

The cardiovascular safety outcomes of newer antidiabetic agents were reviewed.

SUMMARY

Seven randomized, placebo-controlled trials involving patients with type 2 diabetes mellitus with or at risk for cardiovascular disease were reviewed. The trials examined the cardiovascular safety outcomes of the following agents: alogliptin, saxagliptin, and sitagliptin (dipeptidyl peptidase-4 [DPP-4] inhibitors); liraglutide, lixisenatide, and semaglutide (glucagon-like peptide-1 agonists); and empagliflozin (a sodium glucose cotransport-2 inhibitor). The DPP-4 inhibitor and lixisenatide trials showed a neutral effect on cardiovascular events (composite of cardiovascular death, myocardial infarction, or stroke, with or without unstable angina). Empagliflozin showed a significant reduction in cardiovascular events, cardiovascular death, all-cause death, and hospitalization due to heart failure (HF); liraglutide reduced cardiovascular events, cardiovascular death, and all-cause death, and semaglutide reduced cardiovascular events and nonfatal stroke. Most studies showed a neutral effect of the drug on hospitalization for HF; however, saxagliptin and alogliptin (in the subgroups of patients without a history of HF) showed a significant increase while empagliflozin showed a significant reduction in hospitalizations for HF. The data for empagliflozin, liraglutide, and semaglutide are compelling; however, further studies are necessary to confirm observed benefits and better characterize long-term safety and their use as a strategy to reduce cardiovascular events.

CONCLUSION

A review of cardiovascular safety outcomes for new antidiabetic agents found that saxagliptin and alogliptin were associated with an increase in hospitalization for HF. The data for empagliflozin, liraglutide, and semaglutide showed a reduction in cardiovascular events and death or a neutral effect on cardiovascular endpoints.

The Influence of Proton-Pump Inhibitors on Glycemic Control: A Systematic Review of the Literature and a Meta-Analysis

OBJECTIVES

Proton-pump inhibitors (PPIs) have shown antihyperglycemic effects by stimulating insulin secretion. The aim of this study was to analyze the effect of PPIs on glucose metabolism in general and any potential antidiabetes effects in patients with type 2 diabetes.

METHODS

A systematic search was conducted in MEDLINE, Embase, Cochrane and PubMed. Studies using PPIs as interventions and reporting glucose levels, glycated hemoglobin (A1C) levels and insulin levels were selected. Weighted-mean differences (WMDs) were calculated for all outcomes. A random-effects model was used for moderate and high heterogeneity and a fixed-effects model for low heterogeneity data.

RESULTS

The research included 9 studies have involving 320 patients in total. Among patients with type 2 diabetes, those exposed to PPIs did not see significant reductions in A1C levels; WMD -0.36, 95% confidence interval (CI) -0.87, 0.15; p=0.17. Pantoprazole resulted in a statistically significant reduction in A1C levels in patients with type 2 diabetes when compared to control interventions; WMD -0.93, 95% CI -1.49, -0.37; p=0.001. There was no statistically significant difference in other outcomes (p≥0.05).

CONCLUSIONS

This meta-analysis demonstrates that PPIs, in general, do not decrease A1C levels in patients with type 2 diabetes. However, pantoprazole produced significant reductions in A1C levels in patients with type 2 diabetes. Given the limitations and the presence of bias in the primary studies, larger and better-quality studies are warranted.

Monitoring safety and use of old and new treatment options for type 2 diabetic patients: a two-year (2013-2016) analysis

OBJECTIVE

To compare patients' and physicians' perceptions regarding effectiveness and tolerability of non-insulin hypoglycemic drugs in a cohort of type 2 diabetic patients; to verify whether a possible tridimensional link between effectiveness, tolerability, and adherence affects long-term therapeutic outcomes.

METHODS

A two-year observational study was performed in 1389 Type 2 diabetic patients by involving general practitioner clinics and Diabetes Centers. A decimal scale and the Morisky questionnaire were used, respectively, to assess effectiveness and tolerability perceptions, and medication adherence.

RESULTS

Physicians perceived therapy as more efficacious compared to their patients: perceived effectiveness was steady for physicians during the study whereas patients' perception not significantly decreased (mean score from >8 to 7.84 ± 1.69). Physicians assigned higher tolerability scores compared to patients but only at the beginning of the study; interestingly, physicians' tolerability perception was poorer than patients' perception at last follow-up (mean score = 7.57 ± 1.40 vs. 7.88 ± 1.84). Favorable (score >7) patients' perceptions about treatment effectiveness and tolerability were associated with higher adherence. Patients showed medium adherence across the study.

CONCLUSIONS

A mutual relationship between clinical effectiveness, adverse drug reactions, and adherence has been established, significantly impacting the clinical management of diabetic patients. A careful monitoring of this link by clinicians appears therefore necessary.

Dipeptidyl Peptidase-4 Inhibitor–Associated Risk of Bleeding: An Evaluation of Reported Adverse Events

Background: Dipeptidyl peptidase-4 (DPP-4) inhibitors improve glycemic control, and sitagliptin has been associated with a reduction in cardiovascular events. In vivo data suggest reduced platelet activation, and aggregation may play a role, and therefore, increased bleeding risk is possible. Objective: Comparatively assess bleeding risks associated with DPP-4 inhibitors against standard treatment. Methods: Exploratory analyses of adverse event reports (AERs) from the US Food and Drug Administration Adverse Event Reporting System (FAERS) database (2004-2012 periods) were conducted. DPP-4 inhibitor–related bleeding was assessed with metformin as negative control, and aspirin, clopidogrel, and prasugrel illustrated positive comparators. Reporting odds ratios (RORs) and 95% CIs were calculated as a measure of disproportionality of reporting, and RORs were compared across drugs with the Breslow-Day statistics. Results: From 2004 to 2012, 36 298, 4288, and 1202 AERs were found for sitagliptin, saxagliptin, and linagliptin, respectively, with 863, 102, and 14 bleeding complications. The relative reporting rate was not elevated with any DPP-4 inhibitor (sitagliptin: ROR = 0.71, 95% CI = 0.67-0.76; saxagliptin: ROR = 0.72, 95% CI = 0.59-0.87; linagliptin: ROR = 0.35, 95% CI = 0.20-0.59) or with metformin (ROR = 0.77; 95% CI = 0.75-0.78). Sitagliptin showed relatively higher reporting as compared with linagliptin ( P = 0.006) but not with saxagliptin ( P = 0.98). As positive references, antiplatelet drugs demonstrated relatively higher reporting compared with metformin (aspirin: ROR = 1.50, 95% CI = 1.48-1.51; clopidogrel: ROR = 2.28, 95% CI = 2.23-2.33; prasugrel: ROR = 5.09, 95% CI = 4.57-5.67). Conclusion: DPP-4 inhibitors were not associated with an undue increase in bleeding AERs in the FAERS database.

Time-Varying Risk for Breast Cancer Following Initiation of Glucose-Lowering Therapy in Women with Type 2 Diabetes: Exploring Detection Bias

OBJECTIVES

To explore detection bias in the association between glucose-lowering therapies and breast cancer in a cohort of women with type 2 diabetes.

METHODS

This was a retrospective, population-based cohort study. We identified new users of metformin, sulfonylureas, thiazolidinediones and insulin during the index period of January 1, 2003, to December 31, 2010. The main outcome was incident breast cancer, and patients were followed up from drug exposure index date until death, diagnosis of another type of cancer, termination of medical insurance or December 31, 2010. To explore detection bias, we split follow-up time into 2 discrete time periods of 0 to 3 months and 3 months to 6 years after drug index date. We performed time-varying Cox regression analyses, including duration of cumulative drug exposure and ever/never drug exposure for each glucose-lowering therapy into our model. The reference was no use of the same drug-exposure category.

RESULTS

There were 22,169 women with type 2 diabetes, with a mean (SD) age of 53.0 (9.2) years and mean (SD) follow up of 2.2 (1.5) years. Hazard ratios for breast cancer in the first 3 months following initiation of metformin, sulfonylurea or thiazolidinedione were 0.66 (0.43 to 1.02), 0.74 (0.44 to 1.25) and 0.67 (0.38 to 1.18), respectively. In the later period of 3 months to 6 years following drug start, hazard ratios (95% CI) for breast cancer were 1.00 (0.98 to 1.02), 1.01 (0.98 to 1.03) and 0.98 (0.95 to 1.01) for metformin, sulfonylurea and thiazolidinedione cumulative exposure, respectively.

CONCLUSIONS

Our findings suggest that no detection bias exists for glucose-lowering therapies and breast cancer in this population.

Omarigliptin for the treatment of type 2 diabetes

Omarigliptin is a new once-weekly dipeptidyl peptidase-4 (DPP-4) inhibitor developed for the treatment of type 2 diabetes. It is indicated to have favorable effects on glycosylated hemoglobin (HbA_1c), fasting and postmeal plasma glucose. It potently but reversibly inhibits DPP-4 enzyme, which prolongs the circulating half-life of glucagon-like peptide-1 that increases insulin secretion in a glucose-dependent manner. Benefiting from glucose-dependent insulin secretion, omarigliptin is associated with low risk of hypoglycemia. In contrast to the once-daily dipeptidyl peptidase-4 inhibitors (e.g., alogliptin, linagliptin, sitagliptin), once-weekly omarigliptin can improve patients' adherence and thus achieve optimal therapeutic efficacy. Herein, I review the pharmacological and clinical profile of omarigliptin for the treatment of type 2 diabetes based on the available clinical data.

Comparative risk of major cardiovascular events associated with second-line antidiabetic treatments: a retrospective cohort study using UK primary care data linked to hospitalization and mortality records

AIMS

To examine the risk of major cardiovascular events associated with second-line diabetes therapies, in patients with type 2 diabetes, after adjusting for known cardiovascular risk factors.

METHODS

This was a retrospective cohort study of patients prescribed second-line regimens between 1998 and 2011 after first-line metformin. The UK Clinical Practice Research Datalink, with linked national hospitalization and mortality data, for the period up to December 2013, was used. Inverse probability of treatment-weighted time-varying Cox regression models was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for developing a major cardiovascular event (cardiovascular death, myocardial infarction, stroke, acute coronary syndrome, unstable angina, or coronary revascularization) associated with second-line therapies. Analyses adjusted for patient demographic characteristics, comorbidities, glycated haemoglobin, socio-economic status, ethnicity, smoking status and concurrent medications.

RESULTS

A total of 10 118 initiators of a second-line add-on to metformin of either a sulphonylurea (n = 6740), dipeptidyl peptidase-4 (DPP-4) inhibitor (n = 1030) or thiazolidinedione (n = 2348) were identified. After a mean (standard deviation) of 2.4 (1.9) years of follow-up, 386, 36 and 95 major cardiovascular events occurred in sulphonylurea-, DPP-4 inhibitor- and thiazolidinedione-initiators, respectively. In comparison with the metformin-sulphonylurea regimen, adjusted HRs were 0.78 (95% CI 0.55; 1.11) for the metformin-DPP-4 inhibitor regimen and 0.68 (95% CI 0.54; 0.85) for the metformin-thiazolidinedione regimen.

CONCLUSIONS

Thiazolidinedione add-on treatments to metformin were associated with lower risks of major cardiovascular disease or cardiovascular death compared with sulphonylurea add-on treatment to metformin. Lower, but non-statistically significant, risks were also found with DPP-4 inhibitor add-on therapies.

Diabetes treatments and risk of heart failure, cardiovascular disease, and all cause mortality: cohort study in primary care

OBJECTIVE

 To assess associations between risks of cardiovascular disease, heart failure, and all cause mortality and different diabetes drugs in people with type 2 diabetes, particularly newer agents, including gliptins and thiazolidinediones (glitazones).

DESIGN

 Open cohort study.

SETTING

 1243 general practices contributing data to the QResearch database in England.

PARTICIPANTS

 469 688 people with type 2 diabetes aged 25-84 years between 1 April 2007 and 31 January 2015.

EXPOSURES

 Diabetes drugs (glitazones, gliptins, metformin, sulphonylureas, insulin, other) alone and in combination.

MAIN OUTCOME MEASURE

 First recorded diagnoses of cardiovascular disease, heart failure, and all cause mortality recorded on the patients' primary care, mortality, or hospital record. Cox proportional hazards models were used to estimate hazard ratios for diabetes treatments, adjusting for potential confounders.

RESULTS

 During follow-up, 21 308 patients (4.5%) received prescriptions for glitazones and 32 533 (6.9%) received prescriptions for gliptins. Compared with non-use, gliptins were significantly associated with an 18% decreased risk of all cause mortality, a 14% decreased risk of heart failure, and no significant change in risk of cardiovascular disease; corresponding values for glitazones were significantly decreased risks of 23% for all cause mortality, 26% for heart failure, and 25% for cardiovascular disease. Compared with no current treatment, there were no significant associations between monotherapy with gliptins and risk of any complications. Dual treatment with gliptins and metformin was associated with a decreased risk of all three outcomes (reductions of 38% for heart failure, 33% for cardiovascular disease, and 48% for all cause mortality). Triple treatment with metformin, sulphonylureas, and gliptins was associated with a decreased risk of all three outcomes (reductions of 40% for heart failure, 30% for cardiovascular disease, and 51% for all cause mortality). Compared with no current treatment, monotherapy with glitazone was associated with a 50% decreased risk of heart failure, and dual treatment with glitazones and metformin was associated with a decreased risk of all three outcomes (reductions of 50% for heart failure, 54% for cardiovascular disease, and 45% for all cause mortality); dual treatment with glitazones and sulphonylureas was associated with risk reductions of 35% for heart failure and 25% for cardiovascular disease; triple treatment with metformin, sulphonylureas, and glitazones was associated with decreased risks of all three outcomes (reductions of 46% for heart failure, 41% for cardiovascular disease, and 56% for all cause mortality).

CONCLUSIONS

 There are clinically important differences in risk of cardiovascular disease, heart failure, and all cause mortality between different diabetes drugs alone and in combination. Overall, use of gliptins or glitazones was associated with decreased risks of heart failure, cardiovascular disease, and all cause mortality compared with non-use of these drugs. These results, which do not account for levels of adherence or dosage information and which are subject to confounding by indication, might have implications for prescribing of diabetes drugs.

Medication Adherence Affects Risk of New Diabetes Complications

Background: Previous outcomes-based studies of adherence to diabetes medications have focused on glycemic control and are limited by questions of temporality and uncontrolled confounding. Objective: This retrospective cohort study of new oral antidiabetic medication users examined the effect of adherence on risk of incident macrovascular and microvascular complications. Methods: A nationwide integrated insurance claims and laboratory database was used to identify new oral antidiabetic medication users between January 2004 and December 2009. People with preexisting complications were excluded and the remaining cohort was followed until development of a new diabetes complication or December 2010. Medication adherence was calculated at 3-month intervals and entered as a time-dependent variable in a Cox proportional hazards model. Covariables entered in the model included patient demographics, clinical laboratory data, a medical frailty indicator and a mortality risk score from the Johns Hopkins adjusted clinical groups system, and medication use at baseline. Results: Among the 54 505 included patients, the median age was 60 years, 28 125 (52%) were men, 1447 (3%) were considered frail, the mean mortality risk score was 33.7 (±11.1), and 9793 (18%) developed a new diabetes complication. Good adherence (medication possession ratio ≥0.8) was associated with a lower risk of a new microvascular or macrovascular diabetes complication (adjusted hazard ratio = 0.96; 95% CI = 0.92-1.00; P = 0.05). Conclusions: This study design addresses limitations of previous studies and found a small but significantly lower risk of new diabetes complications associated with good adherence to oral antidiabetic medications.

Clinical Update: Cardiovascular Disease in Diabetes Mellitus: Atherosclerotic Cardiovascular Disease and Heart Failure in Type 2 Diabetes Mellitus - Mechanisms, Management, and Clinical Considerations

Cardiovascular disease remains the principal cause of death and disability among patients with diabetes mellitus. Diabetes mellitus exacerbates mechanisms underlying atherosclerosis and heart failure. Unfortunately, these mechanisms are not adequately modulated by therapeutic strategies focusing solely on optimal glycemic control with currently available drugs or approaches. In the setting of multifactorial risk reduction with statins and other lipid-lowering agents, antihypertensive therapies, and antihyperglycemic treatment strategies, cardiovascular complication rates are falling, yet remain higher for patients with diabetes mellitus than for those without. This review considers the mechanisms, history, controversies, new pharmacological agents, and recent evidence for current guidelines for cardiovascular management in the patient with diabetes mellitus to support evidence-based care in the patient with diabetes mellitus and heart disease outside of the acute care setting.

Treated glycosylated hemoglobin levels in individuals with diabetes mellitus vary little by health status: A retrospective cohort study

As choosing wisely has raised the issue of whether some individuals with type 2 diabetes may be overtreated, we examined the intensity of glycemic control across health status strata defined by comorbidities or frailty.This is a retrospective cohort study of commercially insured patients from 50 US states (Clinformatics Data Mart). We evaluated treated HbA1c levels in adults with new diabetes diagnosed between January 2004 and December 2009 who had HbA1C measured after at least 1 year of follow-up.Of 191,590 individuals with diabetes, 78.5% were otherwise healthy, 10.6% had complex health status (3 or more chronic conditions), and 10.9% were very complex (Johns Hopkins Adjusted Clinical Groups frailty marker or end-stage chronic disease). The proportion of patients who were tightly controlled (HbA1C <7%) was similar in otherwise healthy patients (66.1%) and in complex patients (65.8%, P = 0.37), and although it was lower (60.9%, P < 0.0001) in very complex patients, the magnitude of the difference was small. A substantial proportion of complex/very complex patients were taking sulfonylurea or insulin despite being at an increased risk for adverse effects from these agents and having tightly controlled HbA1C: 40.6% had HbA1C <7% and 24% had HbA1C <6.5%. Among patients with HbA1C <7%, use of insulin or sulfonylureas was associated with an increased risk for all-cause hospitalization [aHR 1.54, 95% confidence interval (95% CI) 1.45-1.64] and for emergency room visits (aHR 1.44, 95% CI 1.35-1.53) over the subsequent median 6 months follow-up.Diabetic control was similar regardless of comorbidity burden and frailty status. Despite being at a higher risk for adverse effects, nearly half of complex and very complex patients were still receiving insulin or sulfonylureas despite having treated HbA1C levels <7%, and these patients did exhibit higher risk of all-cause hospitalizations or emergency visits subsequently.

Comparative effectiveness of incretin-based therapies and the risk of death and cardiovascular events in 38,233 metformin monotherapy users

There is limited comparative effectiveness evidence to guide approaches to managing diabetes in individuals failing metformin monotherapy. Our aim was to compare the incidence of all-cause mortality and major adverse cardiovascular events (MACEs) among new metformin monotherapy users initiating a dipeptidyl-peptidase-4 inhibitor (DPP4i), glucagon-like peptide-1 receptor agonist (GLP-1RA), sulfonylurea (SU), thiazolidinedione, or insulin.We conducted a cohort study using the UK-based Clinical Practice Research Datalink. Participants included a cohort of 38,233 new users of metformin monotherapy who initiated a 2nd antidiabetic agent between January 1, 2007 and December 31, 2012 with follow-up until death, disenrollment, therapy discontinuation, or study end-date. A subcohort of 21,848 patients with linked hospital episode statistics (HES) and Office of National Statistics (ONS) data were studied to include MACE and cardiovascular-related death. The primary exposure contrasts, defined a priori, were initiation of a DPP4i versus an SU and initiation of a GLP-1RA versus an SU following metformin monotherapy. Cox proportional hazards models were used to assess the relative differences in time to mortality and MACE between exposure contrasts, adjusting for important baseline patient factors and comedications used during follow-up.The main study cohort consisted of 6213 (16%) patients who initiated a DPP4i, 25,916 initiated an SU (68%), 4437 (12%) initiated a TZD, 487 (1%) initiated a GLP-1RA, 804 (2%) initiated insulin, and 376 (1%) initiated a miscellaneous agent as their 2nd antidiabetic agent. Mean age was 62 years, 59% were male, and mean glycated hemoglobin was 8.8% (92.6 mmol/mol). Median follow-up was 2.7 years (interquartile range 1.3-4.2). Mortality rates were 8.2 deaths/1000 person-years for DPP4i and 19.1 deaths/1000 person-years for SU initiators. Adjusted hazards ratio (aHR) for mortality in DPP4i versus SU initiators = 0.58, 95% CI 0.46 to 0.73, P < 0.001. MACE rates were 19.1/1000 person-years for DPP4i initiators, 15.9/1000 person-years for GLP1-RA initiators versus 33.1/1000 person-years for SU initiators (aHR: DPP4i vs SU initiators = 0.64, 95%CI 0.52-0.80; GLP1RA vs SU initiators = 0.73, 95% CI 0.34-1.55).In this cohort of metformin monotherapy users, 2nd-line DPP4i use was associated with a 42% relative reduction in all-cause mortality and 36% reduction in MACE versus SUs, the most common 2nd-line therapy in our study. GLP-1RAs were not associated with adverse events in this cohort.

Association of Sitagliptin with cardiovascular outcome in diabetic patients: a nationwide cohort study

AIMS

Although dipeptidyl peptidase-4 (DPP-4) inhibitor improves glycemic control, the actual cardiovascular outcomes remain unclear. The objective of this cohort study was to thus evaluate the cardiovascular outcome in diabetic patients who received DPP-4 inhibitors (Sitagliptin).

METHODS

A total of 104,756 new diabetic patients were identified from the Taiwan National Health Insurance Research Database during the period from March 1, 2003 to December 31, 2011. Patients who received Sitagliptin therapy were included as exposures, and up to four age- and sex-matched controls were selected by risk-set sampling. Outcomes such as major adverse cardiovascular diseases (CVD) and deaths were assessed. Logistic regression models were applied to estimate the hazard ratios and 95 % CIs between DPP-4 inhibitor use and cardiovascular outcome.

RESULTS

Over a mean of 14 months, the rates of total CVD per 1000 person-months were significantly lower in Sitagliptin users (3.41 vs. 5.17, p < 0.001), whereas other different CVDs (hazard ratio [HR] 0.59; 95 % confidence interval [CI] 0.48-0.72 for coronary heart disease; HR 0.75; 95 % CI 0.59-0.96 for ischemic stroke; HR 0.86; 95 % CI 0.45-1.65 for peripheral artery occlusive disease) and all-cause mortality (HR 0.56; 95 % CI 0.41-0.74]) were also fewer after adjustment for covariates.

CONCLUSIONS

The results showed a favorable outcome of Sitagliptin as a class on lowering CVD incidence in patients with type 2 diabetes.

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.

Risk of new-onset heart failure in patients using sitagliptin: a population-based cohort study

AIMS

To examine whether patients using sitagliptin at the time of an acute coronary syndrome event are at increased risk of incident heart failure compared with those not exposed.

METHODS

Using US claims data, people with diabetes without a history of heart failure in the 3 years before hospitalization for acute coronary syndrome were identified for the period 2004 to 2010. We used a nested case-control design, whereby cases were patients who developed incident heart failure <30 days after admission to hospital for acute coronary syndrome and were matched by age and sex with up to 10 controls with no heart failure. Subjects exposed or not exposed to sitagliptin in the 90 days before acute coronary syndrome admission were compared using conditional logistic regression after adjustment for clinical and laboratory data, healthcare utilization and propensity scores.

RESULTS

In total, 457 cases of heart failure developing de novo after diagnosis of acute coronary syndrome were matched to 4570 controls. The average age of the subjects was 55 years and 65% were male. Overall, 11 of 147 (7%) people exposed to sitagliptin developed heart failure compared with 446 of the 4880 people not exposed (9%, adjusted odds ratio 0.75, 95% CI 0.38-1.46; P=0.40). Sitagliptin exposure before acute coronary syndrome was not associated with an increased risk of death or heart failure combined (7% vs 9%, adjusted odds ratio 0.66, 95% CI 0.34-1.28).

CONCLUSIONS

In our sample of patients who are at high risk of heart failure after acute coronary syndrome, sitagliptin exposure was not associated with an increased risk of de novo heart failure.

Does Sitagliptin Affect the Rate of Osteoporotic Fractures in Type 2 Diabetes? Population-Based Cohort Study

CONTEXT

Type 2 diabetes and osteoporosis are both common, chronic, and increase with age, whereas type 2 diabetes is also a risk factor for major osteoporotic fractures (MOFs). However, different treatments for type 2 diabetes can affect fracture risk differently, with metaanalyses showing some agents increase risk (eg, thiazolidinediones) and some reduce risk (eg, sitagliptin).

OBJECTIVE

To determine the independent association between new use of sitagliptin and MOF in a large population-based cohort study.

DESIGN, SETTING, AND SUBJECTS

A sitagliptin new user study design employing a nationally representative Unites States claims database of 72 738 insured patients with type 2 diabetes. We used 90-day time-varying sitagliptin exposure windows and controlled confounding by using multivariable analyses that adjusted for clinical data, comorbidities, and time-updated propensity scores.

MAIN OUTCOMES

We compared the incidence of MOF (hip, clinical spine, proximal humerus, distal radius) in new users of sitagliptin vs nonusers over a median 2.2 years follow-up.

RESULTS

At baseline, the median age was 52 years, 54% were men, and median A1c was 7.5%. There were 8894 new users of sitagliptin and 63 834 nonusers with a total 181 139 person-years of follow-up. There were 741 MOF (79 hip fractures), with 53 fractures (4.8 per 1000 person-years) among new users of sitagliptin vs 688 fractures (4.0 per 1000 person-years) among nonusers (P = .3 for difference). In multivariable analyses, sitagliptin was not associated with fracture (adjusted hazard ratio 1.1, 95% confidence interval 0.8-1.4; P = .7), although insulin (P < .001), sulfonylureas (P < .008), and thiazolidinedione (P = .019) were each independently associated with increased fracture risk.

CONCLUSIONS

Even in a young population with type 2 diabetes, osteoporotic fractures were not uncommon. New use of sitagliptin was not associated with fracture, but other commonly used second-line agents for type 2 diabetes were associated with increased risk. These data should be considered when making treatment decisions for those with type 2 diabetes at particularly high risk of fractures.

Cardiovascular Effect of Incretin-Based Therapy in Patients with Type 2 Diabetes Mellitus: Systematic Review and Meta-Analysis

BACKGROUND

To assess the cardiovascular (CV) risk associated with the use of incretin-based therapy in adult patients with type 2 diabetes mellitus (T2DM) primary prevention group with low CV risks.

METHODS

The clinical studies on incretin-based therapy published in medical journals until August 2014 were comprehensively searched using MEDLINE, EMBASE and CENTRAL with no language restriction. The studies were systemically reviewed and evaluated for CV risks using a meta-analysis approach and where they meet the following criteria: clinical trial, incidence of predefined CV disease, T2DM with no comorbidities, age > 18 years old, duration of at least 12 weeks, incretin-based therapy compared with other antihyperglycaemic agents or placebo. Statistical analyses were performed using a Mantel-Haenszel (M-H) test. The odds ratios (OR) and their 95% confidence interval (CI) were estimated and displayed for comparison.

RESULTS

A total of 75 studies comprising 45,648 patients with T2DM were selected. The pooled estimate demonstrated no significance in decreased CV risk with incretin-based therapy versus control (M-H OR, 0.90; 95% CI, 0.81-1.00).

CONCLUSIONS

This meta-analysis suggests that incretin-based therapy show no significant protective effect on CV events in T2DM primary prevention group with low CV risks. Prospective randomized controlled trials are required to confirm the results of this analysis.

Diabetes treatments and risk of amputation, blindness, severe kidney failure, hyperglycaemia, and hypoglycaemia: open cohort study in primary care

OBJECTIVE

To assess the risks of amputation, blindness, severe kidney failure, hyperglycaemia, and hypoglycaemia in patients with type 2 diabetes associated with prescribed diabetes drugs, particularly newer agents including gliptins or glitazones (thiazolidinediones).

DESIGN

Open cohort study in primary care.

SETTING

1243 practices contributing data to the QResearch database in England.

PARTICIPANTS

469,688 patients with type 2 diabetes aged 25-84 years between 1 April 2007 and 31 January 2015.

EXPOSURES

Hypoglycaemic agents (glitazones, gliptins, metformin, sulphonylureas, insulin, and other) alone and in combination.

MAIN OUTCOME MEASURES

First recorded diagnoses of amputation, blindness, severe kidney failure, hyperglycaemia, and hypoglycaemia recorded on patients' primary care, mortality, or hospital records. Cox models estimated hazard ratios for diabetes treatments adjusting for potential confounders.

RESULTS

21,308 (4.5%) and 32,533 (6.9%) patients received prescriptions for glitazones and gliptins during follow-up, respectively. Compared with non-use, glitazones were associated with a decreased risk of blindness (adjusted hazard ratio 0.71, 95% confidence interval 0.57 to 0.89; rate 14.4 per 10,000 person years of exposure) and an increased risk of hypoglycaemia (1.22, 1.10 to 1.37; 65.1); gliptins were associated with a decreased risk of hypoglycaemia (0.86, 0.77 to 0.96; 45.8). Although the numbers of patients prescribed gliptin monotherapy or glitazones monotherapy were relatively low, there were significantly increased risks of severe kidney failure compared with metformin monotherapy (adjusted hazard ratio 2.55, 95% confidence interval 1.13 to 5.74). We found significantly lower risks of hyperglycaemia among patients prescribed dual therapy involving metformin with either gliptins (0.78, 0.62 to 0.97) or glitazones (0.60, 0.45 to 0.80) compared with metformin monotherapy. Patients prescribed triple therapy with metformin, sulphonylureas, and either gliptins (adjusted hazard ratio 5.07, 95% confidence interval 4.28 to 6.00) or glitazones (6.32, 5.35 to 7.45) had significantly higher risks of hypoglycaemia than those prescribed metformin monotherapy, but these risks were similar to those involving dual therapy with metformin and sulphonylureas (6.03, 5.47 to 6.63). Patients prescribed triple therapy with metformin, sulphonylureas, and glitazones had a significantly reduced risk of blindness compared with metformin monotherapy (0.67, 0.48 to 0.94).

CONCLUSIONS

We have found lower risks of hyperglycaemia among patients prescribed dual therapy involving metformin with either gliptins or glitazones compared with metformin alone. Compared with metformin monotherapy, triple therapy with metformin, sulphonylureas, and either gliptins or glitazones was associated with an increased risk of hypoglycaemia, which was similar to the risk for dual therapy with metformin and sulphonylureas. Compared with metformin monotherapy, triple therapy with metformin, sulphonylureas, and glitazones was associated with a reduced risk of blindness. These results, while subject to residual confounding, could have implications for the prescribing of hypoglycaemic drugs.

Risks of cardiovascular diseases associated with dipeptidyl peptidase-4 inhibitors and other antidiabetic drugs in patients with type 2 diabetes: a nation-wide longitudinal study

Background

Several antidiabetic drugs (i.e., sulfonylureas; SU, rosiglitazone) have been reported to be associated with increased risks of cardiovascular diseases (CVD) in patients with type 2 diabetes mellitus (T2DM). Dipeptidyl peptidase-4 inhibitors (DPP4i) are newly available antidiabetic drugs. Most studies only compared DPP4i with a placebo or SU, or targeted a specific CVD event of interest (i.e., heart failure; HF). Comparative research of CVD risks of DPP4i with other antidiabetic drugs (i.e., metformin, thiazolidinediones, meglitinides, acarbose, and insulin) remains scarce. This study was aimed to assess comparative risks of CVD, including ischemic stroke, myocardial infarction (MI) and HF, and hypoglycemia of DPP4i with other antidiabetic drugs.

Methods

We utilized Taiwan’s National Health Insurance Research Database. A total of 123,050 T2DM patients newly prescribed oral antidiabetic treatments were identified in 2009–2010 and followed until 2013. Outcome endpoints included a composite of CVD events: hospitalizations for ischemic stroke, MI and HF, and hypoglycemia. Time-varying Cox proportional hazards regression was applied to assess the time to event hazards of various antidiabetic drugs, adjusted for patients’ demographics, comorbidity, diabetic complications, and co-medications. Additional analyses were performed for the patients with and without CVD history, respectively.

Results

DPP4i users had significantly lower CVD risks as compared to that of non-DPP4i users (adjusted hazard ratio [aHR]: 0.83, 95 % confidence interval [CI]: 0.76–0.91). Compared to DPP4i users, meglitinides (aHR 1.3, 95 % CI 1.20–1.43) and insulin users (aHR 3.73, 95 % CI 3.35, 4.14) had significantly higher risks for composite CVD, as well as those for stroke, MI, HF, and hypoglycemia. Additionally, metformin users had significantly lower risks for composite CVD risk (aHR 0.87, 95 % CI 0.79–0.94), as well as those for MI, HF, and hypoglycemia, as compared to those of DPP4i users. Although there was a trend toward low CVD risks in pioglitazone users, the role of potential confounding by indication cannot be excluded.

Conclusions

DPP4i-treated T2DM patients had lower risks for CVD as compared to those for non-DPP4i users, except metformin users.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0350-4) contains supplementary material, which is available to authorized users.

Risk of overall mortality and cardiovascular events in patients with type 2 diabetes on dual drug therapy including metformin: A large database study from the Cleveland Clinic

BACKGROUND

The aim of the present study was to assess the risk of overall mortality, coronary artery disease (CAD), and congestive heart failure (CHF) in patients with type 2 diabetes mellitus (T2DM) treated with metformin (MF) and an additional antidiabetic agent.

METHODS

A retrospective cohort study was conducted using an academic health center enterprise-wide electronic health record (EHR) system to identify 13,185 adult patients (>18 years) with T2DM from January 2008 to June 2013 and received a prescription for MF in combination with a sulfonylurea (SU; n = 9419), thiazolidinedione (TZD; n = 1846), dipeptidyl peptidase-4 inhibitor (DPP-4i; n = 1487), or a glucagon-like peptide-1 receptor agonist (GLP-1a; n = 433). Multivariate Cox models with propensity analysis were used to compare cohorts, with MF+SU serving as the comparator group.

RESULTS

The mean (±SD) age was 60.6 ± 12.6 years, with 54.6% male and 75.8% Caucasians. The median follow-up was 4 years. There were 1077 deaths, 1733 CAD events, and 528 CHF events in 55,100 person-years of follow-up. A higher risk of CHF was observed with MF+DPP-4i use (hazard ratio [HR] 1.104; 95% confidence interval [CI] 1.04-1.17; P = 0.001). A trend towards improved overall survival for users of MF+TZD (HR 0.86; 95% CI 0.74-1.0; P = 0.05) and MF+GLP-1a (HR 0.569; 95% CI 0.30-1.07; P = 0.08) was observed. No significant differences in the risk of CAD were identified.

CONCLUSIONS

Consistent with recent studies, our results raise concern for an increased risk of CHF with use of DPP-4i.

Dipeptidyl Peptidase-4 Inhibitor Use Is Not Associated With Acute Pancreatitis in High-Risk Type 2 Diabetic Patients: A Nationwide Cohort Study

To analyze the association between use of DPP-4 inhibitors and acute pancreatitis in high-risk type 2 diabetic patients. A retrospective nationwide cohort study was conducted using the Taiwan National Health Insurance claim database. The risk associated with sitagliptin was compared to that with acarbose, a second-line antidiabetic drug prescribed for patients with similar diabetes severity and with a known neutral effect on pancreatitis. Between January 1, 2009 and December 31, 2010, a total of 8526 sitagliptin initiators and 8055 acarbose initiators who had hypertriglyceridemia or prior hospitalization history for acute pancreatitis were analyzed for the risk of hospitalization due to acute pancreatitis stratified for baseline propensity score. In the crude analysis, sitagliptin was associated with a decreased risk of acute pancreatitis (hazard ratio [HR] 0.74; 95% confidence interval [CI]: 0.62-0.88) compared to acarbose in diabetic patients with prior history of hospitalization for pancreatitis or hypertriglyceridemia. The association was abolished after stratification for propensity score quintiles (adjusted HR 0.95; 95% CI: 0.79-1.16). Similar results were found separately in both patients' histories of prior hospitalization of acute pancreatitis (adjusted HR 0.97; 95% CI: 0.76-1.24) and those with hypertriglyceridemia (adjusted HR 0.86; 95% CI: 0.65-1.13). No significant association was found for different durations or accumulative doses of sitagliptin. In the stratified analysis, no significant effect modification was found in relation to patients' characteristics. Use of sitagliptin was not associated with an increased risk of acute pancreatitis in high-risk diabetic patients with hypertriglyceridemia or with history of acute pancreatitis.

Sitagliptin for Type 2 diabetes: a 2015 update

Sitagliptin, a dipeptidyl peptidase 4 inhibitor, was the first in its class to receive approval from the US FDA in 2006 for the treatment of Type 2 diabetes mellitus. It has been evaluated in numerous clinical trials and has several attractive features as an antidiabetic agent, including a low risk for hypoglycemia, a neutral effect on weight, and an ability to be used in chronic kidney disease and more. This article provides an up-to-date discussion of the pharmacokinetics/pharmacodynamics, clinical efficacy, safety and tolerability of sitagliptin.

Effects on All-cause Mortality and Cardiovascular Outcomes in Patients With Type 2 Diabetes by Comparing Insulin With Oral Hypoglycemic Agent Therapy: A Meta-analysis of Randomized Controlled Trials

PURPOSE

Retrospective, case-control studies and prospective randomized controlled trials (RCTs) on insulin treatment for diabetic patients yielded contradictory mortality and cardiovascular outcomes. We aimed to evaluate the effects of insulin versus oral hypoglycemic agents (OHAs) on all-cause mortality and cardiovascular outcomes in patients with type 2 diabetes (T2D).

METHODS

We searched Medline, Embase, Cochrane Central Register of Controlled Trials, Chinese Biological Medicine Database, China National Knowledge Infrastructure, Chinese Technical Periodicals, and Wanfang Data, up to July 10, 2015, for RCTs on insulin and OHAs that assessed all-cause mortality and/or cardiovascular death as primary end points. We derived pooled risk ratios (RRs) as summary statistics.

RESULTS

Three trials were included in which 7649 patients received insulin and 8322 received OHAs, with mean (SD) diabetes duration of 5.0 (6.2) and 4.4 (5.9) years, respectively. Insulin did not differ from OHAs in all-cause mortality (RR = 1.00; 95% CI, 0.93-1.07), cardiovascular death (RR = 1.00; 95% CI, 0.91-1.09), myocardial infarction (RR = 1.04; 95% CI, 0.93-1.16), angina (RR = 0.97; 95% CI, 0.88-1.06), sudden death (RR = 1.02; 95% CI, 0.66-1.56), or stroke (RR = 1.01; 95% CI, 0.88-1.15). Insulin reduced the risk of heart failure compared with OHAs (RR = 0.87; 95% CI, 0.75-0.99). In the subgroup of secondary prevention of cardiovascular diseases (CVDs) or very high risk of CVDs, insulin did not differ from OHAs in all-cause mortality (RR = 0.99; 95% CI, 0.92-1.07), cardiovascular death (RR = 0.99; 95% CI, 0.90-1.09), myocardial infarction (RR = 1.01; 95% CI, 0.88-1.15), heart failure (RR = 0.69; 95% CI, 0.34-1.40), or stroke (RR = 1.05; 95% CI, 0.90-1.21).

IMPLICATIONS

Insulin did not provide a clear benefit over OHAs in all-cause mortality or cardiovascular outcomes in the patients with T2D. Insulin therapy has many shortcomings, including inconvenience (injection, strict blood glucose monitoring), hypoglycemia, and obvious weight gain. Thus, we conclude that no robust evidence supports the active use of insulin for this population at present.

Use of an electronic health record to identify prevalent and incident cardiovascular disease in type 2 diabetes according to treatment strategy

BACKGROUND

The increasing use of electronic health records (EHRs) in clinical practice offers the potential to investigate cardiovascular outcomes over time in patients with type 2 diabetes (T2D).

OBJECTIVE

To develop a methodology for identifying prevalent and incident cardiovascular disease (CVD) in patients with T2D who are candidates for therapeutic intensification of glucose-lowering therapy.

METHODS

Patients with glycated hemoglobin (HbA1c) ≥7% (53 mmol/mol) while receiving 1-2 oral diabetes medications (ODMs) were identified from an EHR (2005-2011) and grouped according to intensification with insulin (INS) (n=372), a different class of ODM (n=833), a glucagon-like peptide receptor 1 agonist (GLP-1RA) (n=59), or no additional therapy (NAT) (n=2017). Baseline prevalence of CVD was defined by documented International Classification of Diseases Ninth Edition (ICD-9) codes for coronary artery disease, cerebrovascular disease, or other CVD with first HbA1c ≥7% (53 mmol/mol). Incident CVD was defined as a new ICD-9 code different from existing codes over 4 years of follow-up. ICD-9 codes were validated by a chart review in a subset of patients.

RESULTS

Sensitivity of ICD-9 codes for CVD ranged from 0.83 to 0.89 and specificity from 0.90 to 0.96. Baseline prevalent (INS vs ODM vs GLP-1RA vs NAT: 65% vs 39% vs 54% vs 59%, p<0.001) and incident CVD (Kaplan-Meier estimates: 58%, 31%, 52%, and 54%, p=0.002) were greater in INS group after controlling for differences in baseline HbA1c (9.2±2.0% vs 8.3±1.2% vs 8.2±1.3% vs 7.7±1.1% (77 vs 67 vs 66 vs 61 mmol/mol), p<0.001) and creatinine (1.15±0.96 vs 1.10±0.36 vs 1.01±0.35 vs 1.07±0.45 mg/dL, p=0.001).

CONCLUSIONS

An EHR can be an effective method for identifying prevalent and incident CVD in patients with T2D.

Sitagliptin use and risk of acute pancreatitis in type 2 diabetes mellitus: A population-based case-control study in Taiwan

BACKGROUND

There is still lack of definite evidence to establish the association between sitagliptin use and acute pancreatitis. The study aimed to test this issue in Taiwan.

METHODS

This case-control study was designed to analyze the database of the Taiwan National Health Insurance Program. There were 349 subjects with type 2 diabetes mellitus aged 20-84 with a first-attack of acute pancreatitis from 2009 to 2011 as the case group and 1116 randomly selected subjects with type 2 diabetes mellitus without acute pancreatitis as the control group. Both groups were matched with sex, age, comorbidities, and index year of diagnosing acute pancreatitis. Current use of sitagliptin was defined as subjects who had their last tablet of sitagliptin ≤7 days before the date of diagnosing acute pancreatitis. Late use of sitagliptin was defined as subjects who had their last tablet of sitagliptin between 8 and 30 days before the date of diagnosing acute pancreatitis. Never use of sitagliptin was defined as subjects who never had a sitagliptin prescription. The risk of acute pancreatitis associated with sitagliptin use was estimated by the odds ratio (OR) and 95% confidence interval (CI) using the multivariable logistic regression model.

RESULTS

After statistical correction for potential confounders, the adjusted OR of acute pancreatitis was 2.47 for subjects with current use of sitagliptin (95% CI 0.84, 7.28), when compared with those never using sitagliptin, but without statistical significance. The adjusted OR decreased to 1.14 for subjects with late use of sitagliptin (95% CI 0.66, 1.98), but without statistical significance.

CONCLUSIONS

No significant association is detected between sitagliptin use and acute pancreatitis in type 2 diabetes mellitus.

The Comparative Effectiveness of Angiotensin-Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers in Patients With Diabetes

The evidence examining the effect of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) on mortality in high-risk patients is conflicting. To further examine this controversy, the authors compared outcomes between ACE inhibitors and ARBs in a large clinical diabetes registry. A retrospective cohort of 87,472 incident users followed for 105,702 patient-years was analyzed. Average age was 53.1±10.1 years, 54.2% were men, and 14.4% had cardiovascular disease. All-cause hospitalization or all-cause mortality, the composite primary endpoint, occurred in 10,943 (12.5%) patients. Compared with ACE inhibitors, the adjusted hazard for ARBs was 0.90 (95% confidence interval, 0.87-0.94) for all-cause hospitalization or mortality; 0.95 (0.65-1.40) for mortality; 0.90 (0.87-0.94) for all-cause hospitalization; and 0.81 (0.74-0.89) for cardiovascular admission. ARB use was associated with a reduced, not increased, risk of hospitalization/mortality relative to ACE inhibition. This was driven by lower hospitalization, with a null mortality result.

Sitagliptin After Ischemic Stroke in Type 2 Diabetic Patients: A Nationwide Cohort Study

The cerebrovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase-4 inhibitor, in patients with type 2 diabetes mellitus (T2DM) with ischemic stroke remains uncertain. The aim of this study was to assess the efficacy and safety of sitagliptin in patients with T2DM with recent ischemic stroke. We analyzed data from the Taiwan National Health Insurance Research Database between March 1, 2009, and December 31, 2011. Ischemic stroke patients were identified from individuals with T2DM. Patients who received sitagliptin were compared with those who did not to evaluate the cardiovascular safety and efficacy of sitagliptin. The primary outcome was a composite of ischemic stroke, myocardial infarction, or cardiovascular death. A total of 5145 type 2 diabetic patients with ischemic stroke met our inclusion criteria and were followed for up to 2.83 years (mean, 1.17 years). Overall, 1715 patients (33.3%) received sitagliptin and 3430 patients (66.7%) did not. The primary composite outcome occurred in 190 patients in the sitagliptin group (11.1%) and in 370 patients in the comparison group (10.8%) (hazard ratio [HR] = 1.02; 95% confidence interval [CI], 0.85-1.21). Patients treated with sitagliptin had a similar risk of ischemic stroke, hemorrhagic stroke, and all-cause mortality with an HR of 0.95 (95% CI, 0.78-1.16, P = 0.612), 1.07 (95% CI, 0.55-2.11, P = 0.834), and 1.00 (95% CI, 0.82-1.22, P = 0.989), respectively, compared with patients not treated with sitagliptin. Treatment with sitagliptin in type 2 diabetic patients with recent ischemic stroke was not associated with increased or decreased risks of adverse cerebrovascular outcomes.

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.

Incretin-based drugs and adverse pancreatic events: almost a decade later and uncertainty remains

Over the past few years, substantial clinical data have been presented showing that incretin-based therapies are effective glucose-lowering agents. Specifically, glucagon-like peptide 1 receptor agonists demonstrate an efficacy comparable to insulin treatment with minimal hypoglycemia and have favorable effects on body weight. Thus, many of the unmet clinical needs noted from prior therapies are addressed by these agents. However, even after many years of use, many continue to raise concerns about the long-term safety of these agents and, in particular, the concern with pancreatitis. This clearly remains a complicated topic. Thus, in this issue of Diabetes Care, we continue to update our readers on this very important issue by presenting two studies evaluating incretin-based medications and risk of pancreatitis. Both have undergone significant revisions based on peer review that provided significant clarification of the data. We applaud both author groups for being extremely responsive in providing the additional data and revisions requested by the editorial team. As such, because of the critical peer review, we feel both articles achieve the high level we require for Diabetes Care and are pleased to now present them to our readers. In keeping with our aim to comprehensively evaluate this topic, we asked for additional commentaries to be prepared. In the narrative outlined below, Dr. Laurent Azoulay provides a commentary about the remaining uncertainty in this area and also discusses the results from a nationwide population-based case-control study. In the narrative preceding Dr. Azoulay's contribution, Prof. Edwin A.M. Gale provides a commentary on the report that focuses on clinical trials of liraglutide in the treatment of diabetes. From the journal's perspective, both of the articles on pancreatitis and incretin-based therapies reported in this issue have been well vetted, and we feel both of the commentaries are insightful.

Incretin-based drugs and risk of acute pancreatitis: A nested-case control study within a healthcare database

To assess the association between use of incretin-based drugs for diabetes mellitus and the occurrence of acute pancreatitis. A population-based, nested case-control study was performed within a cohort of 166,591 patients from the Lombardy region (Italy) aged 40 years or older who were newly treated with oral antihyperglycaemic agents between 2004 and 2007. Cases were 666 patients who experienced acute pancreatitis from April 1, 2008 until December 31, 2012. For each case patient, up to 20 controls were randomly selected from the cohort and matched on gender, age at cohort entry, and date of index prescription. Conditional logistic regression was used to model the risk of acute pancreatitis associated with use of incretin-based drugs within 30 days before hospitalization, after adjustment for several risk factors, including the use of other antihyperglycaemic agents. Sensitivity analyses were performed in order to account for possible sources of systematic uncertainty. Use of incretin-based drugs within 30 days was reported by 17 (2.6%) cases of acute pancreatitis versus 193 (1.5%) controls. The corresponding multivariate odds ratio was 1.75 (95% confidence interval, 1.02 to 2.99). Slightly lower and no significant excess risks were observed by shortening (15 days) and increasing (60 and 90 days) the time-window at risk. This study supports a possible increased risk of acute pancreatitis in relation to use of incretin-based drugs reported in a few previous studies. However, given the potential for bias and the inconsistency with other studies, additional investigations are needed to clarify the safety of incretin-based-drugs.

Glucose-lowering with exogenous insulin monotherapy in type 2 diabetes: dose association with all-cause mortality, cardiovascular events and cancer

AIMS

To evaluate the association between insulin exposure and all-cause mortality, incident major adverse cardiovascular events (MACE) and incident cancer in people with type 2 diabetes treated with insulin monotherapy.

METHODS

For this retrospective study, people with type 2 diabetes who progressed to insulin monotherapy from the year 2000 were identified from the UK Clinical Practice Research Datalink. The risks of progression to serious adverse outcomes were compared using Cox proportional hazards models. In the main analysis, insulin exposure was introduced into the model as prescribed international units per kilogram per day, as a cumulative, continuous, annually updated, time-dependent covariable.

RESULTS

A total of 6484 subjects with type 2 diabetes who progressed to treatment with insulin monotherapy from the year 2000 onwards were followed for a mean of 3.3 years. The event numbers were as follows: deaths, n = 1110; incident MACE, n = 342; incident cancers, n = 382. Unadjusted event rates were 61.3 deaths per 1000 person-years, 26.4 incident MACE per 1000 person-years and 24.6 incident cancers per 1000 person-years. The adjusted hazard ratios in relation to 1-unit increases in insulin dose were 1.54 [95% confidence interval (CI) 1.32-1.78] for all-cause mortality, 1.37 (95% CI 1.05-1.81) for MACE and 1.35 (95% CI 1.04-1.75) for cancer.

CONCLUSIONS

There was an association between increasing exogenous insulin dose and increased risk of all-cause mortality, MACE and cancer in people with type 2 diabetes. The limitations of observational studies mean that this should be further investigated using an interventional study design.

Dipeptidyl peptidase-4 inhibitors and the risk of community-acquired pneumonia in patients with type 2 diabetes

AIMS

To determine whether the use of dipeptidyl peptidase-4 (DPP-4) inhibitors is associated with an increased risk of community-acquired pneumonia.

METHODS

The UK Clinical Practice Research Datalink and the Hospital Episodes Statistics database were used to conduct a nested case-control analysis within a cohort of new users of antidiabetic drugs between 2007 and 2012. Incident cases of hospitalization for community-acquired pneumonia were matched with up to 20 controls on age, duration of treated diabetes, calendar year and duration of follow-up. Conditional logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for hospitalization for community-acquired pneumonia associated with current use of DPP-4 inhibitors compared with current use of two or more oral antidiabetic drugs.

RESULTS

The cohort included 49,653 patients, of whom 562 were hospitalized for community-acquired pneumonia during follow-up (incidence rate 5.2/1000 person-years). Compared with current use of two or more oral antidiabetic drugs, current use of DPP-4 inhibitors was not associated with an increased risk of hospitalized community-acquired pneumonia overall (adjusted OR 0.80, 95% CI 0.50-1.29) or according to duration of use (p for trend = 0.57).

CONCLUSIONS

The use of DPP-4 inhibitors was not associated with an increased risk of hospitalization for community-acquired pneumonia. Additional research is needed to assess the association between these drugs and other serious infections.

Efficacy and safety of sitagliptin added to insulin in Japanese patients with type 2 diabetes: the EDIT randomized trial

Aims

To clarify the efficacy and safety of adding sitagliptin to insulin therapy in Japanese patients with suboptimally controlled type 2 diabetes (T2DM).

Study Design and Methods

This was a 24-week, prospective, randomized, open-labeled, controlled trial. Patients with T2DM who were suboptimally controlled despite receiving at least twice daily injection of insulin were enrolled in the study. The patients were randomized to continuation of insulin treatment (Insulin group) or addition of sitagliptin 50 to 100 mg daily to insulin treatment (Ins+Sita group). The primary outcome was change in HbA1c at week 24.

Results

Adding sitagliptin to insulin significantly reduced HbA1c from 7.9 ± 1.0% at baseline to 7.0 ± 0.8% at week 24 (P <0.0001), while there was no significant change in HbA1c in the Insulin group (7.8 ± 0.7% vs. 7.8 ± 1.1%, P = 0.32). The difference in HbA1c reduction between the groups was 0.9% (95% confidence interval, 0.4 to 1.5, P = 0.01). There was no significant weight gain in either group. Incidence of hypoglycemia was significantly reduced in the Ins+Sita group compared with the Insulin group. Treatment satisfaction was improved in the Ins+Sita group. Baseline HbA1c level and beta cell function were associated with the magnitude of reduction in HbA1c in the Ins+Sita group.

Conclusion

Adding sitagliptin to insulin reduced HbA1c without weight gain or increase in hypoglycemia, and improved treatment satisfaction in Japanese patients with T2DM who were suboptimally controlled despite at least twice daily injection of insulin.

Trial Registration

The University Hospital Medical Information Network (UMIN) Clinical Trials Registry UMIN000004678

Safety of dipeptidyl peptidase-4 inhibitors for treating type 2 diabetes

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) occupy a growing place in the armamentarium of drugs used for the management of hyperglycemia in type 2 diabetes, although some safety concerns have been raised in recent years.

AREAS COVERED

An updated review providing an analysis of available safety data (meta-analyses, randomized controlled trials, observational cohort and case-control studies and pharmacovigilance reports) with five commercialized DPP-4 inhibitors (sitagliptin, vildagliptin, saxagliptin, alogliptin, linagliptin). A special focus is given to overall safety profile; pancreatic adverse events (AEs) (acute pancreatitis, pancreatic cancer); overall cardiovascular safety (myocardial infarction and stroke); congestive heart failure concern and finally, safety in special populations (elderly, renal impairment).

EXPERT OPINION

The good tolerance/safety profile of DPP-4 inhibitors has been largely confirmed, including in more fragile populations (elderly, renal impairment) with almost no increased risk of infection or gastrointestinal AEs, no weight gain and a minimal risk of hypoglycemia. Although an increased risk of acute pancreatitis and pancreatic cancer was suspected, the complete set of available data appears reassuring so far. Cardiovascular safety of DPP-4 inhibitors has been proven but an unexpected increased risk of heart failure has been reported which should be confirmed in ongoing trials and better understood. Further postmarketing surveillance is recommended.

Sitagliptin: a review of its use in patients with type 2 diabetes mellitus

Sitagliptin (Januvia(®), Xelevia™, Glactiv(®), Tesavel(®)) is an orally administered, potent and highly selective inhibitor of dipeptidyl peptidase-4 (DPP-4) and was the first agent of its class to be approved for use in the management of adults with type 2 diabetes. Numerous randomized placebo- or active comparator-controlled trials have demonstrated the efficacy of sitagliptin in terms of improving glycaemic control in patients with type 2 diabetes, including its use as monotherapy, initial combination therapy (usually with fixed-dose combinations of sitagliptin/metformin), or add-on therapy to metformin or to other antihyperglycaemic drugs, with or without metformin. The primary endpoint of the clinical trials was the reduction from baseline in glycosylated haemoglobin (HbA1c), although sitagliptin also showed beneficial effects for other endpoints, such as the proportion of patients who achieved target HbA1c, and reductions from baseline in fasting plasma glucose (FPG) levels and 2-h postprandial glucose (PPG) levels. Sitagliptin was generally well tolerated in clinical trials, had a low risk of hypoglycaemia (although this depends on background therapy) and had a neutral effect on body weight. Despite concerns regarding a possible increased risk of rare pancreatic adverse events (e.g. pancreatitis) with glucagon-like peptide-1 (GLP-1)-based therapies, such as GLP-1 receptor agonists and DPP-4 inhibitors, no causal association has been found; regulators in Europe recently conducted a review of available data, concluding that there is little evidence that these drugs could cause pancreatic inflammation or pancreatic cancer. A similar review is planned in the USA and postmarketing surveillance will continue. Thus, oral sitagliptin is an effective and generally well tolerated treatment option for the management of patients with type 2 diabetes.