The effect of sitagliptin on cardiovascular risk profile in Korean patients with type 2 diabetes mellitus: a retrospective cohort study

Drugs Interfering with Insulin Resistance and Their Influence on the Associated Hypermetabolic State in Severe Burns: A Narrative Review

It has become widely accepted that insulin resistance and glucose hypermetabolism can be linked to acute pathologies, such as burn injury, severe trauma, or sepsis. Severe burns can determine a significant increase in catabolism, having an important effect on glucose metabolism and on muscle protein metabolism. It is imperative to acknowledge that these alterations can lead to increased mortality through organ failure, even when the patients survive the initial trauma caused by the burn. By limiting the peripheral use of glucose with consequent hyperglycemia, insulin resistance determines compensatory increased levels of insulin in plasma. However, the significant alterations in cellular metabolism lead to a lack of response to insulin's anabolic functions, as well as to a decrease in its cytoprotective role. In the end, via pathological insulin signaling associated with increased liver gluconeogenesis, elevated levels of glucose are detected in the blood. Several cellular mechanisms have been incriminated in the development of insulin resistance in burns. In this context, the main aim of this review article is to summarize some of the drugs that might interfere with insulin resistance in burns, taking into consideration that such an approach can significantly improve the prognosis of the burned patient.

Incident cancer risk in dipeptidyl peptidase-4 inhibitor-treated patients with type 2 diabetes mellitus

Objective

It is known that patients with diabetes are susceptible to cancer development due to long-standing diabetic conditions. This study aimed to investigate new-onset cancer risk associated with dipeptidyl peptidase-4 (DPP-4) inhibitors as compared to metformin, the first-line antidiabetic agent with promising anticancer activity, in patients with type 2 diabetes mellitus (T2DM).

Methods

A retrospective cohort study of adult T2DM patients was performed at a tertiary care hospital in Korea. Patients who received comparison therapies during 2008–2017 were propensity score (PS)-matched in a 1:1 ratio either to the DPP-4 inhibitors group or to the metformin group in accordance with their primary antidiabetic therapy.

Results

A total of 1538 patients (769 in each group) were found eligible for study entry. Although the rate of newly diagnosed malignancy, irrespective of specific sites or types, was numerically less frequent in the DPP-4 inhibitors group, the difference in overall cancer risk between groups was not statistically significant (HR=1.00, 95% CI=0.56–1.80, P=0.998). The PS-matched patients were further stratified by relevant patient factors and diabetes severity. No signal of increased risk of malignant complications among DPP-4 inhibitor-receiving diabetic patients was detected in any of the individual strata, nor in the subgroup patients where insulin-exposed patients were excluded from study analyses in consideration of its carcinogenic properties. Patient death or incident pancreatitis events were seldom encountered in both treatment groups; hence such risks were assessed as negligible with the use of either antidiabetic therapy.

Conclusion

This PS-matched cohort study demonstrated no elevated risk of malignant complications with DPP-4 inhibitor treatment relative to metformin treatment among T2DM patients, irrespective of patient sex, age, comorbid conditions, and diabetes severity status. Similar results were confirmed in the subgroup analyses where a potential confounding effect due to the between-group disparity in insulin co-therapy was eliminated by excluding insulin-exposed patients from risk assessments.

Durability of initial antidiabetic monotherapy and subsequent treatment adjustment patterns among newly treated type 2 diabetes patients

BACKGROUND

As newly available antidiabetic drugs (ADs) are used more commonly as initial hypoglycemic choice for early stage diabetes patients, there is an urgent need to investigate how these agents may differ in treatment durability relative to metformin. This study aimed to investigate the incidence and risk of treatment adjustment among newly treated type 2 diabetes mellitus (T2DM) patients receiving an oral AD as initial monotherapy.

METHODS

T2DM patients registered in the National Health Insurance Program who were newly prescribed an oral AD were identified. Time to treatment addition or switch to alternative antidiabetic therapy was determined using the Kaplan-Meier survival analysis. Cox proportional hazards regression was performed to estimate the hazard ratio (HR) after adjusting for potential confounding factors.

RESULTS

The median time to treatment adjustment was shorter for sulfonylureas (SUs), dipeptidyl peptidase-4 (DPP-4) inhibitors, alphaglucosidase (AG) inhibitors, and thiazolidinediones (TZDs) compared to that for metformin. Initiation of therapy with SUs or DPP-4 inhibitors was associated with a significantly higher risk of both treatment addition and switching than with metformin (HR 1.49 versus 1.47 for overall treatment adjustment, respectively). In contrast, among incident users of AG inhibitors or TZDs, only the hazard of switch was substantially increased compared to metformin starters (6.19, 95% confidence interval [CI] 5.77-6.64 and 7.31, 95% CI 6.35-8.42, respectively). When addition and switch events were collectively assessed, the risk of treatment adjustment was significantly elevated in all non-metformin cohorts.

CONCLUSION

Our results demonstrated that the durability of metformin as an initial monotherapy was superior to that of other ADs, including newer classes of antidiabetics, and appeared to be more effective in delaying treatment adjustment in real-world clinical practice.

Cost-consequence analysis of sitagliptin versus sulfonylureas as add-on therapy for the treatment of diabetic patients in Italy

Objective

Diabetes mellitus is a chronic disease related to a significant impact in both epidemiologic and economic terms. In Italy, around 3.6 million people are affected by diabetes and this number is expected to increase significantly in the next few years. As recommended by current national and international guidelines, metformin (Met) is prescribed as first-line pharmacological treatment, and many pharmacological alternatives are available for patients uncontrolled with Met monotherapy. Despite the availability of many innovative oral antidiabetic drugs (OADs), such as dipeptidyl peptidase 4 inhibitors (DPP4-i) and its first-in-class sitagliptin (SITA), which entered the Italian market in the last 10 years, their usage is consistently lower than traditional drugs such as sulfonylureas (SUs). In fact, due to higher acquisition costs, the prescription of innovative OADs in Italy is restricted to specialist, resulting in a prominent usage of traditional OAD that can be prescribed also by general practitioners (GPs). A cost consequence analysis (CCA) was performed in order to compare SITA with SU, as second-line therapy in add-on to Met, in terms of costs and related clinical events over 36 months.

Methods

A CCA was conducted on a hypothetical cohort of 100,000 type 2 diabetes mellitus (T2DM) patients uncontrolled with Met monotherapy, from both the Italian National Health Service (INHS) and societal perspective. Therefore, both direct (drugs, self-monitoring, hypoglycemia, major cardiovascular events [MACEs], and switch to insulin) and indirect costs (expressed in terms of productivity losses) were evaluated. Clinical and economic data were collected through Italian national tariffs, literature, and experts' opinions. Three expert clinicians finally validated data inputs. To assess robustness of base case results, a one-way sensitivity analysis (OWSA) and a conservative scenario analysis - excluding MACEs - were carried out.

Results

In the base case analysis, the higher drug costs related to SITA were offset by other management costs (ie, lower use of devices for glycemia self-monitoring, lower incidence of hypoglycemia and MACE, and delay to insulin switch). As a result, the economic evaluation showed that, compared to SU, SITA was cost saving from both societal (-€61,217,723) and INHS (-€51,846,442) perspectives over 3 years as add-on to Met. The base case results were also confirmed by the scenario analysis and by the OWSA performed on the key parameters. The adoption of SITA, in a cohort of 100,000 diabetes patients, would avoid 26,882 non-severe hypoglycemic events, 6,528 severe hypoglycemic events, and 1,562 MACEs.

Conclusion

This analysis suggests that, compared to SU, SITA could be a sustainable and cost-saving alternative for the management of T2DM patients uncontrolled with Met monotherapy from both clinical and economic perspectives.

Comparative safety for cardiovascular outcomes of DPP-4 inhibitors versus glimepiride in patients with type 2 diabetes: A retrospective cohort study

Concerns about the cardiovascular safety of dipeptidyl peptidase-4 (DPP-4) inhibitors persist. This study sought to determine whether there is a differential risk of hospitalization for cardiovascular diseases (CVDs) between DPP-4 inhibitors and glimepiride.We conducted this retrospective cohort study by using the Korean National Health Insurance Service database from December 1, 2008, to December 31, 2013. The study subjects were new users of DPP-4 inhibitors or glimepiride for type 2 diabetes. Outcome was defined as hospitalization for CVDs, including angina pectoris, myocardial infarction, transient cerebral ischemic attack, heart failure, or cerebrovascular disease or any procedure involving coronary artery bypass grafting or percutaneous coronary intervention. We used a Cox proportional hazard model to estimate the adjusted hazard ratios (aHRs) and their 95% confidence intervals (CIs), to assess the risk of CVDs associated with the use of DPP-4 inhibitors compared with glimepiride.The cohort consisted of 1,045,975 patients, with 6504 in the DPP-4 inhibitors group and 13,447 in the glimepiride group. No significant increased risk of total CVDs was found (aHR, 0.87; 95% CI, 0.75-1.01) in the DPP-4 inhibitors versus glimepiride group. A decreased risk of hospitalization for CVDs was found among patients with a history of visit for CVDs (aHR, 0.73; 95% CI, 0.56-0.97) or with >2.5 years' duration of type 2 diabetes (aHR, 0.77; 95% CI, 0.66-0.91) in the DPP-4 inhibitors versus glimepiride group.DPP-4 inhibitors did not increase cardiovascular risk compared with glimepiride regardless of CVD history and diabetes duration.