Treatment with incretins does not increase the risk of pancreatic diseases compared to older anti-hyperglycaemic drugs, when added to metformin: real world evidence in people with Type 2 diabetes

Risk of Pancreatic Cancer and Use of Dipeptidyl Peptidase 4 Inhibitors in Patients with Type 2 Diabetes: A Propensity Score-Matching Analysis

BACKGRUOUND

The effects of dipeptidyl peptidase 4 (DPP-4) inhibitors over the course of long-term treatment remain unclear, and concerns have been raised regarding the role of DPP-4 inhibitors in carcinogenesis in the pancreas. Earlier studies of pancreatic adverse events have reported conflicting results.

METHODS

This study analyzed Korean National Health Insurance Service data from January 2009 to December 2012. Patients who had type 2 diabetes mellitus and took two or more oral glucose-lowering drugs (GLDs) were included. Patients prescribed DPP-4 inhibitors (n=51,482) or other GLDs (n=51,482) were matched at a 1:1 ratio using propensity score matching. The risk of pancreatic cancer was calculated using Kaplan-Meier curves and Cox proportional-hazards regression analysis.

RESULTS

During a median follow-up period of 7.95 years, 1,051 new cases of pancreatic cancer were identified. The adjusted hazard ratio (HR) for DPP-4 inhibitor use was 0.99 (95% confidence interval [CI], 0.88 to 1.12) compared with the other GLD group. In an analysis limited to cases diagnosed with pancreatic cancer during hospitalization, the adjusted HR for the use of DPP-4 inhibitors was 1.00 (95% CI, 0.86 to 1.17) compared with patients who took other GLDs. Using the other GLD group as the reference group, no trend was observed for elevated pancreatic cancer risk with increased DPP-4 inhibitor exposure.

CONCLUSION

In this population-based cohort study, DPP-4 inhibitor use over the course of relatively long-term follow-up showed no significant association with an elevated risk of pancreatic cancer.

A systematic review and meta-analysis of observational studies of the association between the use of incretin-based therapies and the risk of pancreatic cancer

BACKGROUND

Some early reports in the medical literature have raised concern about a possible increased risk of pancreatic cancer associated with the use of two broad classes of incretin-based therapies, dipeptidyl peptidase-4 inhibitors, and glucagon-like peptide-1 receptor agonists. This possibility has been somewhat mitigated by the null findings meta-analyses of randomized controlled trials, but the usefulness of their findings was hampered by serious shortcomings of lack of power and representativeness. These shortcomings can typically be addressed by observational studies, but observational studies on the topic have yielded conflicting findings. A systematic review and meta-analysis of observational studies was performed to qualitatively and quantitatively appraise the totality of evidence on the association between the use of incretin-based therapies and the risk of pancreatic cancer in routine clinical practice.

METHODS

The PubMed, Web of Science, Embase, and Google Scholar databases were searched. The study quality was appraised using the ROBINS-I tool and based on the presence of pharmacoepidemiology biases. A random-effects model was used to estimate the summary relative risks with corresponding CIs.

RESULTS

A total of 14 studies were included. The qualitative assessment revealed that all studies had inadequate follow-up (≤5 years), 12 studies were suspected to suffer from time-lag bias (due to inappropriate choice of comparator group) to varying extent, five studies included prevalent users, five studies did not implement exposure lag period, five studies had a serious risk of bias due to confounding, and one study had a time-window bias. The quantitative assessment showed no indication of an increased risk when all studies were pooled together (RR 1.04, 95% CI 0.87, 1.24) and when the analysis was restricted to the studies with the least bias (RR 0.77, 95% CI 0.51, 1.17). However, the pooled RRs were more frequently higher in the studies with less rigorous design and analysis. Specifically, a tendency toward an increased risk was observed in the studies with (RR 1.34, 95% CI 1.04, 1.72) or possibly with (RR 1.10, 95% CI 0.89, 1.36) time-lag bias, in the studies that did not apply (RR 1.23, 95% CI 0.93, 1.63) or with potentially inadequate exposure lag period of 6 months (RR 1.13, 95% CI 0.66, 1.94), in the studies that inappropriate comparator group of a combination of unspecified (RR 1.49, 95% CI 1.25, 1.78) or non-insulin (RR 1.15, 95% CI 0.93, 1.42) antidiabetic drugs, and in the studies with serious risk of bias due to confounding (RR 1.18, 95% CI 0.56, 2.49).

CONCLUSIONS

In summary, the totality of evidence from observational studies does not support the claim that the use of incretin-based therapies is associated with an increased risk of pancreatic cancer in routine clinical practice. The increased risk of pancreatic cancer observed in observational studies reflects bias resulting from suboptimal methodological approaches, which need to be avoided by future studies.

Incretin based therapy and pancreatic cancer: Realising the reality

Incretin-based therapies like glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors help maintain the glycaemic control in patients with type 2 diabetes mellitus with additional systemic benefits and little risk of hypoglycaemia. These medications are associated with low-grade chronic pancreatitis in animal models inconsistently. The incidence of acute pancreatitis was also reported in some human studies. This inflammation provides fertile ground for developing pancreatic carcinoma (PC). Although the data from clinical trials and population-based studies have established safety regarding PC, the pathophysiological possibility that low-grade chronic pancreatitis leads to PC remains. We review the existing literature and describe the relationship between incretin-based therapies and PC.

Metformin reduces lipid accumulation in HepG2 cells via downregulation of miR-33b

INTRODUCTION

Here, we aimed to investigate whether the beneficial effects of metformin on lipid accumulation is mediated through regulation of miR-33b.

METHODS

The expression of the genes and miRNAs and protein levels were evaluated using real-time PCR and western blot, respectively. To investigate the potential role of miR-33b in lipid accumulation, the mimic of the miR-33b was transfected into HepG2 cells.

RESULTS

We found that metformin reduces high glucose-induced lipid accumulation in HepG2 cells through inhibiting of SREBP1c and FAS and increasing the expression of CPT1 and CROT. Overexpression of miR-33b significantly prevented the decreasing effect of metformin on lipid content and intra and extra triglyceride levels. Importantly, miR-33b mimic inhibited the increasing effects of metformin on the expression of CPT1 and CROT.

CONCLUSION

These findings suggest that metformin attenuates high glucose-induced lipid accumulation in HepG2 cell by downregulating the expression of miR-33b.

Amaranth, quinoa and chia bioactive peptides: a comprehensive review on three ancient grains and their potential role in management and prevention of Type 2 diabetes

Worldwide prevalence of Type 2 Diabetes (T2D) has become a major concern with several implications for public health, economy, and social well-being, especially in developing countries. Conventional pharmacological management of T2D have proved effective, but possess underlying side effects, leading the scientific community to research alternative compounds that exert beneficial effects on current therapeutic targets of T2D. Bioactive peptides (BAPs) from food sources, have shown relative advantages in this matter, moreover, BAPs have proved to impart anti-diabetic activity through one or more mechanisms such as enzymatic inhibition of α-glucosidase, α-amylase and DPP-IV. Several plants and animal have been used as protein sources of anti-diabetic BAPs, in the sense of this matter, the pseudo-cereals amaranth and quinoa, along with the ancestral grain chia, have gained attention. Due, to their high protein content and balanced amino-acid composition, along with proved anti-diabetic features, the three seeds are top choices for the obtention of anti-diabetic BAPs. With a comprehensive overview of the most recent reported in silico and in vitro anti-diabetic studies in relation to biomarkers α-glucosidase, α-amylase and DPP-IV, the present review aims to examine the current knowledge of amaranth, quinoa and chia derived anti-diabetic BAPs and their effects on T2D therapeutic markers.

The present and future scope of real-world evidence research in diabetes: What questions can and cannot be answered and what might be possible in the future?

The last decade has witnessed an exponential growth in the opportunities to collect and link health-related data from multiple resources, including primary care, administrative, and device data. The availability of these "real-world," "big data" has fuelled also an intense methodological research into methods to handle them and extract actionable information. In medicine, the evidence generated from "real-world data" (RWD), which are not purposely collected to answer biomedical questions, is commonly termed "real-world evidence" (RWE). In this review, we focus on RWD and RWE in the area of diabetes research, highlighting their contributions in the last decade; and give some suggestions for future RWE diabetes research, by applying well-established and less-known tools to direct RWE diabetes research towards better personalized approaches to diabetes care. We underline the essential aspects to consider when using RWD and the key features limiting the translational potential of RWD in generating high-quality and applicable RWE. Only if viewed in the context of other study designs and statistical methods, with its pros and cons carefully considered, RWE will exploit its full potential as a complementary or even, in some cases, substitutive source of evidence compared to the expensive evidence obtained from randomized controlled trials.

DPP-4 Inhibition and the Path to Clinical Proof

In the 1990s it was discovered that the enzyme dipeptidyl peptidase-4 (DPP-4) inactivates the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). DPP-4 inhibition results in raised levels of the two incretin hormones which in turn result in lowering of circulating glucose through stimulation of insulin secretion and inhibition of glucagon secretion. Since then, several small orally available molecules have been developed with DPP-4 inhibitory action. Early studies in the 1990s showed that the DPP-4 inhibitors improve glycemia in animals. Subsequent clinical studies during the 2000s showed a glucose-lowering action of DPP-4 inhibitors also in human subjects with type 2 diabetes. This action was seen when DPP-4 inhibitors were used both as monotherapy and as add-on to other therapies, i.e., metformin, sulfonylureas, tiazolidinediones or exogenous insulin. The DPP-4 inhibitors were also found to have a low risk of adverse events, including hypoglycemia. Five of the DPP-4 inhibitors (sitagliptin, vildagliptin, alogliptin, saxagliptin and linagliptin) were approved by regulatory authorities and entered the market between 2006 and 2013. DPP-4 inhibitors have thereafter undergone long-term cardiovascular outcome trials, showing non-inferiority for risk of major acute cardiovascular endpoints. Also the risk of other potential adverse events is low in these long-term studies. DPP-4 inhibitors are at present included in guidelines as a glucose-lowering concept both as monotherapy and in combination therapies. This article summarizes the development of the DPP-4 inhibition concept from its early stages in the 1990s. The article underscores that the development has its basis in scientific studies on pathophysiology of type 2 diabetes and the importance of targeting the islet dysfunction, that the development has been made possible through academic science in collaboration with the research-oriented pharmaceutical industry, and that the development of a novel concept takes time and requires focused efforts, persistence and long-term perserverance.