No evidence of increased risk of malignancies in patients with diabetes treated with insulin detemir: a meta-analysis

Diabetes mellitus and risk of breast cancer: a large-scale, prospective, population-based study

BACKGROUND

The objective of this study was to evaluate associations of diabetes overall, type 1 diabetes (T1D), and type 2 diabetes (T2D) with breast cancer (BCa) risk.

METHODS

We included 250,312 women aged 40-69 years between 2006 and 2010 from the UK Biobank cohort. Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) were calculated for associations of diabetes and its two major types with the time from enrollment to incident BCa.

RESULTS

We identified 8182 BCa cases during a median follow-up of 11.1 years. We found no overall association between diabetes and BCa risk (aHR = 1.02, 95% CI = 0.92-1.14). When accounting for diabetes subtype, women with T1D had a higher risk of BCa than women without diabetes (aHR = 1.52, 95% CI = 1.03-2.23). T2D was not associated with BCa risk overall (aHR = 1.00, 95% CI = 0.90-1.12). However, there was a significantly increased risk of BCa in the short time window after T2D diagnosis.

CONCLUSIONS

Though we did not find an association between diabetes and BCa risk overall, an increased risk of BCa was observed shortly after T2D diagnosis. In addition, our data suggest that women with T1D may have an increased risk of BCa.

[Diagnosis and insulin therapy of type 1 diabetes mellitus (Update 2023)]

This guideline summarizes diagnosis of type 1 diabetes, including accompanying autoimmune disorders, insulin therapy regimens and glycemic target values.

Use of Antihyperglycemic Drugs and Risk of Cancer in Patients with Diabetes

PURPOSE OF REVIEW

Diabetes is associated with an increased risk for several types of cancer. Therefore, use of antihyperglycemic medications to lower blood glucose may modify cancer risk. Here we review available data on the link between the most common classes of antihyperglycemic agents and cancer risk among patients with diabetes.

RECENT FINDINGS

A database search was conducted between February 2022 and June 2022 on PubMed and Embase for systematic reviews and meta-analyses investigating the association between antihyperglycemic agents and risk of cancer. Use of biguanides such as metformin is associated with 20-30% lower risk for all cancer incidence, and somewhat greater benefit for cancer-related mortality. Alpha-glucosidase inhibitors, e.g., acarbose, have not been consistently associated with cancer. Similarly, no consistent effects have been reported for thiazolidinediones, but the relationship with cancer seems to depend on the type of drug, dose, and duration of treatment. Exposure to various types of incretin-based therapies (glucagon-like peptide-1 agonists and dipeptidyl peptidase-4 inhibitors) has not been found to significantly modify cancer risk. Inhibitors of sodium glucose cotransporter-2 may raise risk for bladder cancer and reduce risk for gastrointestinal cancer. Use of insulin and insulin analogs is associated with a significant increase in total cancer risk by almost 50% compared to other antihyperglycemic drugs. Likewise, insulin secretagogues like sulfonylureas have generally been linked to greater risk for cancer by ~ 20%, although these associations may be agent-specific and dose-dependent. Current evidence suggests that the risk of cancer associated with the use of antihyperglycemic medications among patients with diabetes depends on the class of drug and type of agent, dosage, and duration of treatment. More research is needed to delineate the mechanisms by which these agents affect the process of carcinogenesis.

Impact of Insulin Therapies on Cancer Incidence in Type 1 and Type 2 Diabetes: A Population-Based Cohort Study in Reggio Emilia, Italy

Simple Summary

The aim of this population-based study was to assess the impact of insulin treatment on cancer incidence in subjects with type 1 or type 2 diabetes in Italy. We found that insulin use was associated with a 20% excess for all sites cancer incidence among people with type 2 diabetes, while people with type 1 diabetes did not show any excess. Liver, pancreatic, bladder, and neuroendocrine cancers seem to be the sites with strongest association.

Abstract

Objective: To assess the effect of insulin on cancer incidence in type 1 (T1DM) and type 2 diabetes (T2DM). Methods: The cohort included all 401,172 resident population aged 20–84 in December 2009 and still alive on December 2011, classified for DM status. Drug exposure was assessed for 2009–2011 and follow up was conducted from 2012 to 2016 through the cancer registry. Incidence rate ratios (IRRs) were computed for all sites and for the most frequent cancer sites. Results: among residents, 21,190 people had diabetes, 2282 of whom were taking insulin; 1689 cancers occurred, 180 among insulin users. The risk for all site was slightly higher in people with T2DM compared to people without DM (IRR 1.21, 95% CI 1.14–1.27), with no excess for T1DM (IRR 0.73, 95% CI 0.45–1.19). The excess in T2DM remained when comparing with diet-only treatment. In T2DM, excess incidence was observed for liver and pancreas and for NETs: 1.76 (95% CI 1.44–2.17) and 1.37 (95% CI 0.99–1.73), respectively. For bladder, there was an excess both in T1DM (IRR 3.00, 95% CI 1.12, 8.02) and in T2DM (IRR1.27, 95% CI 1.07–1.50). Conclusions: Insulin was associated with a 20% increase in cancer incidence. The risk was higher for liver, pancreatic, bladder and neuroendocrine tumours.

Impaired Glucose Metabolism, Anti-Diabetes Medications, and Risk of Thyroid Cancer

Simple Summary

An epidemiologic link exists between obesity, insulin resistance, diabetes, and some cancers, such as breast cancer and colon cancer. The prevalence of obesity and diabetes is increasing, and additional epidemiologic data suggest that there may be a link between obesity and risk of thyroid abnormalities. Factors that may link obesity and diabetes with thyroid proliferative disorders include elevated circulating levels of insulin, increased body fat, high blood sugars, and exogenous insulin use. However, mechanisms underlying associations of obesity, diabetes, and thyroid proliferative disorders are not yet fully understood. The present manuscript reviews and summarizes current evidence of mechanisms and epidemiologic associations of obesity, insulin resistance, and use of anti-diabetes medications with benign and malignant proliferative disorders of the thyroid.

Abstract

The prevalence of obesity is progressively increasing along with the potential high risk for insulin resistance and development of type 2 diabetes mellitus. Obesity is associated with increased risk of many malignancies, and hyperinsulinemia has been proposed to be a link between obesity and cancer development. The incidence of thyroid cancer is also increasing, making this cancer the most common endocrine malignancy. There is some evidence of associations between obesity, insulin resistance and/or diabetes with thyroid proliferative disorders, including thyroid cancer. However, the etiology of such an association has not been fully elucidated. The goal of the present work is to review the current knowledge on crosstalk between thyroid and glucose metabolic pathways and the effects of obesity, insulin resistance, diabetes, and anti-hyperglycemic medications on the risk of thyroid cancer development.

[Diagnosis and insulin therapy of type 1 diabetes mellitus (Update 2019)]

This guideline summarizes diagnosis of type 1 diabetes, including accompanying autoimmune disorders, insulin therapy regimens and glycemic target values.

Metformin and blood cancers

Type 2 diabetes mellitus and cancer are correlated with changes in insulin signaling, a pathway that is frequently upregulated in neoplastic tissue but impaired in tissues that are classically targeted by insulin in type 2 diabetes mellitus. Many antidiabetes treatments, particularly metformin, enhance insulin signaling, but this pathway can be inhibited by specific cancer treatments. The modulation of cancer growth by metformin and of insulin sensitivity by anticancer drugs is so common that this phenomenon is being studied in hundreds of clinical trials on cancer. Many meta-analyses have consistently shown a moderate but direct effect of body mass index on the incidence of multiple myeloma and lymphoma and the elevated risk of leukemia in adults. Moreover, new epidemiological and preclinical studies indicate metformin as a therapeutic agent in patients with leukemia, lymphomas, and multiple myeloma. In this article, we review current findings on the anticancer activities of metformin and the underlying mechanisms from preclinical and ongoing studies in hematologic malignancies.

Genome-Wide Analyses Identify Filamin-A As a Novel Downstream Target for Insulin and IGF1 Action

Insulin analogs were developed to improve diabetes therapy. However, certain modifications introduced into the insulin molecule were shown to enhance their affinity to the insulin-like growth factor-1 receptor (IGF1R). Most tumors, including endometrial cancers, express high levels of IGF1R. The present study was aimed at identifying the entire set of genes that are differentially activated by insulin glargine or detemir, in comparison to insulin and IGF1, in Type 1 and Type 2 endometrial cancer cell lines (ECC-1 and USPC-1, respectively). Global gene expression analyses demonstrated a ligand-dependent upregulated expression of filamin-A (FLNA), a gene that encodes an actin filament cross-linking protein, in both endometrial cancer cell types. Silencing experiments linked to migration assays confirmed the role of FLNA in cell growth and motility. Our data suggest that the activation of distinct sets of genes by glargine may lead to stimulation of specific pathways or, alternatively, may provide additive effects, different from those classically induced by insulin. Given that metastases are probably the main factor contributing to tumor invasiveness, the identification of FLNA as a downstream target for insulin-like hormones may be of translational relevance in oncology. Clinical studies in endometrial cancer may add further relevant information regarding the possible differential actions of insulin analogs with respect to native insulin.

Long-Term Use of Long-Acting Insulin Analogs and Breast Cancer Incidence in Women With Type 2 Diabetes

Purpose

The association between long-acting insulin analogs and increased breast cancer risk is uncertain, particularly with the short follow-up in previous studies. We assessed this risk long term in women with type 2 diabetes.

Methods

A population-based cohort of women 40 years or older, all of whom were treated with long-acting (glargine, detemir) or neutral protamine Hagedorn (NPH) insulin between 2002 and 2012, was formed using the United Kingdom’s Clinical Practice Research Datalink. Women were followed until February 2015 or breast cancer diagnosis. Cox proportional hazards models were used to estimate adjusted hazard ratios (HRs) and 95% CIs of incident breast cancer, comparing long-acting insulin analogs with NPH overall, as well as by duration and cumulative dose.

Results

The cohort included 22,395 women who received insulin treatment, with 321 incident breast cancer events occurring during up to 12 years of follow-up (incidence rate 3.3 per 1,000 person-years). Compared with NPH insulin, insulin glargine was associated with an increased risk of breast cancer (HR, 1.44; 95% CI, 1.11 to 1.85), mainly increasing 5 years after glargine initiation (HR, 2.23; 95% CI, 1.32 to 3.77) and after > 30 prescriptions (HR, 2.29; 95% CI, 1.26 to 4.16). The risk was particularly elevated among prior insulin users (HR, 1.53; 95% CI, 1.10 to 2.12) but not for new users, which included fewer patients and for which one cannot rule out an HR of 1.81. The risk associated with insulin detemir was not significantly elevated (HR, 1.17; 95% CI, 0.77 to 1.77).

Conclusion

Long-term use of insulin glargine is associated with an increased risk of breast cancer in women with type 2 diabetes. The risk associated with insulin detemir remains uncertain because there are fewer users of this insulin.

Observational Registry of Basal Insulin Treatment in Patients with Type 2 Diabetes in China: Safety and Hypoglycemia Predictors

BACKGROUND

The Observational Registry of Basal Insulin Treatment (ORBIT) study evaluated the safety of basal insulin (BI) in real-world settings in China.

METHODS

We analyzed 9002 patients with type 2 diabetes (T2D) inadequately controlled with oral hypoglycemic agents from 8 geographic regions and 2 hospital tiers in China who initiated and maintained BI treatment. Body weight and hypoglycemic episodes were recorded at baseline and 3 and 6 months. Serious adverse events (SAEs) were recorded at 3 and 6 months.

RESULTS

Age, gender, inpatient/outpatient status, body mass index, glycated hemoglobin (HbA1c) at baseline and at the end of study, T2D duration, microvascular complications, BI type, combination with insulin secretagogues, self-monitoring of blood glucose frequency, and insulin dosage, all predicted hypoglycemia. BI use generally did not induce significant weight gain (0.02 kg); weight gain with insulin detemir (-0.30 kg) was less than that with neutral protamine Hagedorn (NPH) insulin (0.20 kg) or insulin glargine (0.05 kg). Overall, general hypoglycemia incidence (5.6% vs. 7.7%) and annual event rate (1.6 vs. 1.8) were similar before and after BI initiation, whereas a slight decrease was noted in severe hypoglycemia incidence (0.6%-0.3%) and frequency (0.05-0.03 events/patient-year). The general hypoglycemia rate was lowest with insulin glargine, whereas there was no significant difference in severe hypoglycemia among the three BI groups. Overall, 3.5% of patients had at least one SAE during the study. Most SAEs were found to be unrelated to BI treatment.

CONCLUSIONS

Real-world BI use, particularly insulin detemir and glargine, was associated with only slight weight gain and low hypoglycemia risk in patients with T2D in China.

The expanding role of metformin in cancer: an update on antitumor mechanisms and clinical development

Metformin has been used for nearly a century to treat type 2 diabetes mellitus. Epidemiologic studies first identified the association between metformin and reduced risk of several cancers. The anticancer mechanisms of metformin involve both indirect or insulin-dependent pathways and direct or insulin-independent pathways. Preclinical studies have demonstrated metformin's broad anticancer activity across a spectrum of malignancies. Prospective clinical trials involving metformin in the chemoprevention and treatment of cancer now number in the hundreds. We provide an update on the anticancer mechanisms of metformin and review the results thus far available from prospective clinical trials investigating metformin's efficacy in cancer.

Cancer risks of anti-hyperglycemic drugs for type 2 diabetes treatment - a clinical appraisal

AIM

A clinical appraisal of existing scientific literature sought to assess the need for long-term prospective epidemiological studies to investigate an increased cancer risk of anti-hyperglycemic medication in type 2 diabetes.

METHOD

A focus statement was formulated as: "With a higher risk of cancers in patients with type 2 diabetes, all anti-hyperglycemic drugs should undergo long-term, prospective epidemiological studies for cancer risks." Field surveys were sent to practicing physicians and endocrinologists to identify the currently prevalent level of acceptance of this statement. Subsequently, a meeting with a six-member panel of key opinion leaders was held to discuss published evidence in support and against the statement. This publication reviews the publications and discussion points brought forth in this meeting and their effect on statement acceptance by the panel.

RESULTS

Whereas the majority of field survey responders primarily agreed with the statement, panel members were divided in their statement support. This division remained intact after review of the literature.

CONCLUSIONS

While there was evidence that type 2 diabetes is associated with an increased risk of cancer, existing studies seemed insufficient to definitively demonstrate a link between cancer risk and use of specific anti-hyperglycemic therapies.

All-Cause and Cause-Specific Mortality among Users of Basal Insulins NPH, Detemir, and Glargine

Background

Insulin therapy in type 2 diabetes may increase mortality and cancer incidence, but the impact of different types of basal insulins on these endpoints is unclear. Compared to the traditional NPH insulin, the newer, longer-acting insulin analogues detemir and glargine have shown benefits in randomized controlled trials. Whether these advantages translate into lower mortality among users in real life is unknown.

Objective

To estimate the differences in all-cause and cause-specific mortality rates between new users of basal insulins in a population-based study in Finland.

Methods

23 751 individuals aged ≥40 with type 2 diabetes, who initiated basal insulin therapy in 2006–2009 were identified from national registers, with comprehensive data for mortality, causes of death, and background variables. Propensity score matching was performed on characteristics. Follow-up time was up to 4 years (median 1.7 years).

Results

2078 deaths incurred. With NPH as reference, the adjusted HRs for all-cause mortality were 0.39 (95% CI, 0.30–0.50) for detemir, and 0.55 (95% CI, 0.44–0.69) for glargine. As compared to glargine, the HR was 0.71 (95% CI, 0.54–0.93) among detemir users. Compared to NPH, the mortality risk for both cardiovascular causes as well as cancer were also significantly lower for glargine, and especially for detemir in adjusted analysis. Furthermore, the results were robust in various sensitivity analyses.

Conclusion

In real clinical practice, mortality was substantially higher among users of NPH insulin as compared to insulins detemir or glargine. Considering the large number of patients who require insulin therapy, this difference in risk may have major clinical and public health implications. Due to limitations of the observational study design, further investigation using an interventional study design is warranted.

Looking at the carcinogenicity of human insulin analogues via the intrinsic disorder prism

Therapeutic insulin, in its native and biosynthetic forms as well as several currently available insulin analogues, continues to be the protein of most interest to researchers. From the time of its discovery to the development of modern insulin analogues, this important therapeutic protein has passed through several stages and product generations. Beside the well-known link between diabetes and cancer risk, the currently used therapeutic insulin analogues raised serious concerns due to their potential roles in cancer initiation and/or progression. It is possible that structural variations in some of the insulin analogues are responsible for the appearance of new oncogenic species with high binding affinity to the insulin-like growth factor 1 (IGF1) receptor. The question we are trying to answer in this work is: are there any specific features of the distribution of intrinsic disorder propensity within the amino acid sequences of insulin analogues that may provide an explanation for the carcinogenicity of the altered insulin protein?

Effect of Long-Acting Insulin Analogs on the Risk of Cancer: A Systematic Review of Observational Studies

OBJECTIVE

Observational studies examining the association between long-acting insulin analogs and cancer incidence have produced inconsistent results. We conducted a systematic review of these studies, focusing on their methodological strengths and weaknesses.

RESEARCH DESIGN AND METHODS

We systematically searched MEDLINE and EMBASE from 2000 to 2014 to identify all observational studies evaluating the relationship between the long-acting insulin analogs and the risk of any and site-specific cancers (breast, colorectal, prostate). We included cohort and case-control studies published in English on insulin glargine and detemir and any cancer incidence among patients with type 1 or 2 diabetes. The methodological assessment involved the inclusion of prevalent users, inclusion of lag periods, time-related biases, and duration of follow-up between insulin initiation and cancer incidence.

RESULTS

A total of 16 cohort and 3 case-control studies met our inclusion criteria. All studies evaluated insulin glargine, and four studies also examined insulin detemir. Follow-up ranged from 0.9 to 7.0 years. Thirteen of 15 studies reported no association between insulin glargine and detemir and any cancer. Four of 13 studies reported an increased risk of breast cancer with insulin glargine. In the quality assessment, 7 studies included prevalent users, 11 did not consider a lag period, 6 had time-related biases, and 16 had short (<5 years) follow-up.

CONCLUSIONS

The observational studies examining the risk of cancer associated with long-acting insulin analogs have important methodological shortcomings that limit the conclusions that can be drawn. Thus, uncertainty remains, particularly for breast cancer risk.

Treatment with insulin (analogues) and breast cancer risk in diabetics; a systematic review and meta-analysis of in vitro, animal and human evidence

INTRODUCTION

Several studies have suggested that anti-diabetic insulin analogue treatment might increase cancer risk. The aim of this study was to review the postulated association between insulin and insulin analogue treatment and breast cancer development, and plausible mechanisms.

METHOD

A systematic literature search was performed on breast cell-line, animal and human studies using the key words 'insulin analogue' and 'breast neoplasia' in MEDLINE at PubMed, EMBASE, and ISI Web of Science databases. A quantitative and qualitative review was performed on the epidemiological data; due to a limited number of reported estimates, a meta-analysis was performed for glargine only. A comprehensive overview was composed for in vitro and animal studies. Protein and gene expression was analysed for the cell lines most frequently used in the included in vitro studies.

RESULTS

In total 16 in vitro, 5 animal, 2 in vivo human and 29 epidemiological papers were included. Insulin AspB10 showed mitogenic properties in vitro and in animal studies. Glargine was the only clinically available insulin analogue for which an increased proliferative potential was found in breast cancer cell lines. However, the pooled analysis of 13 epidemiological studies did not show evidence for an association between insulin glargine treatment and an increased breast cancer risk (HR 1.04; 95 % CI 0.91-1.17; p=0.49) versus no glargine in patients with diabetes mellitus. It has to be taken into account that the number of animal studies was limited, and epidemiological studies were underpowered and suffered from methodological limitations.

CONCLUSION

There is no compelling evidence that any clinically available insulin analogue (Aspart, Determir, Glargine, Glulisine or Lispro), nor human insulin increases breast cancer risk. Overall, the data suggests that insulin treatment is not involved in breast tumour initiation, but might induce breast tumour progression by up regulating mitogenic signalling pathways.

Impaired glucose metabolism treatment and carcinogenesis

Carbohydrate metabolism disorders increase the risk of carcinogenesis. Diabetes mellitus alters numerous physiological processes that may encourage cancer growth. However, treating impaired glucose homeostasis may actually promote neoplasia; maintaining proper glucose plasma concentrations reduces metabolic stresses, however, certain medications may themselves result in oncogenic effects. A number of previous studies have demonstrated that metformin reduces the cancer risk. However, the use of sulfonylurea derivatives correlates with an increased risk of developing a malignancy. Another form of treatment, insulin therapy, involves using various forms of insulin that differ in pharmacodynamics, pharmacokinetics and efficacy. Previous studies have indicated that certain insulin variants also affect the cancer risk. The results from analyses that address the safety of long-lasting insulin types raise the most concern regarding the increased risk of malignancy. Rapid development of novel diabetic medications and their widespread use carries the risk of potentially increased rates of cancer, unnoticeable in limited, randomized, controlled trials. In the present review, the results of clinical and epidemiological studies are evaluated to assess the safety of anti-hyperglycemic medications and their effect on cancer risk and outcomes.

Antidiabetic drugs and risk of cancer

Antidiabetic drugs are an important group of medications used worldwide. They differ from each other in the mechanisms of lowering blood glucose as well as in adverse effects that may affect the course of the treatment and its efficacy. In recent years, new drugs have been discovered in order to improve the maintenance of proper blood glucose level and to reduce unwanted effects of these drugs. Their growing administration is related to the increasing incidence of diabetes observed in all countries in the world. Epidemiological data indicate that diabetes increases the risk of cancer, as well as the risk of death linked with neoplasms. It is still unknown whether this is an effect of antidiabetic drugs or just the effect of diabetes itself. In recent years there have been numerous investigations and meta-analyzes, based on both comparative and cohort studies trying to establish the relationship between antidiabetic pharmacotherapy and the incidence and mortality due to cancer. According to their findings, most of antidiabetic drugs increase the risk of cancer while only few of them show antitumor properties. Different mechanisms of action of glucose-lowering drugs may be responsible for these effects. However, most of the published studies concerning the influence of these drugs on cancer incidence were designed with some limitations and differed from each other in the approach. In this review, we discuss the association between antidiabetic drugs used in monotherapy or polytherapy and cancer risk, and consider potential mechanisms responsible for the observed effects.

Proliferative and signaling activities of insulin analogues in endometrial cancer cells

Insulin analogues have been developed to achieve further improvement in the therapy of diabetes. However, modifications introduced into the insulin molecule may enhance their affinity for the insulin-like growth factor-1 receptor (IGF1R). Hyperinsulinemia has been identified as a risk factor for endometrial cancer. We hypothesized that insulin analogues may elicit atypical proliferative and signaling activities in endometrial cancer cells. Our results demonstrate that glargine, but not detemir, stimulated cell proliferation, displayed an anti-apoptotic effect, and had a positive effect on cell cycle progression in endometrial cancer cell lines ECC-1 and USPC-1. In addition, we showed that glargine and detemir induced dual activation of the insulin receptor (INSR) and IGF1R in both cell types. Furthermore, we showed that glargine elicited signaling events that are markedly different from those induced by insulin. In conclusion, our data support the concept that, although insulin analogues were designed to display insulin-like metabolic effects, glargine and, possibly, additional analogues exhibit IGF1-like activities and, accordingly, may function as IGF1 analogues.

Mammary gland tumor promotion by chronic administration of IGF1 and the insulin analogue AspB10 in the p53R270H/⁺WAPCre mouse model

INTRODUCTION

Insulin analogues are structurally modified molecules with altered pharmaco-kinetic and -dynamic properties compared to regular human insulin used by diabetic patients. While these compounds are tested for undesired mitogenic effects, an epidemiological discussion is ongoing regarding an association between insulin analogue therapy and increased cancer incidence, including breast cancer. Standard in vivo rodent carcinogenesis assays do not pick up this possible increased carcinogenic potential.

METHODS

Here we studied the role of insulin analogues in breast cancer development. For this we used the human relevant mammary gland specific p53R270H/⁺WAPCre mouse model. Animals received life long repeated treatment with four different insulin (-like) molecules: normal insulin, insulin glargine, insulin X10 (AspB10) or insulin-like growth factor 1 (IGF1).

RESULTS

Insulin-like molecules with strong mitogenic signaling, insulin X10 and IGF1, significantly decreased the time for tumor development. Yet, insulin glargine and normal insulin, did not significantly decrease the latency time for (mammary gland) tumor development. The majority of tumors had an epithelial to mesenchymal transition phenotype (EMT), irrespective of treatment condition. Enhanced extracellular signaling related kinase (Erk) or serine/threonine kinase (Akt) mitogenic signaling was in particular present in tumors from the insulin X10 and IGF1 treatment groups.

CONCLUSIONS

These data indicate that insulin-like molecules with enhanced mitogenic signaling increase the risk of breast cancer development. Moreover, the use of a tissue specific cancer model, like the p53R270H/⁺WAPCre mouse model, is relevant to assess the intrinsic pro-carcinogenic potential of mitogenic and non-mitogenic biologicals such as insulin analogues.

Diabetes mellitus: influences on cancer risk

Diabetes mellitus and cancer are common conditions, and their co-diagnosis in the same individual is not infrequent. The relative risks associated with type 2 diabetes are greater than twofold for hepatic, pancreatic, and endometrial cancers. The relative risk is somewhat lower, at 1.2-1.5-fold for colorectal, breast, and bladder cancers. In comparison, the relative risk of lung cancer is less than 1. The evidence for other malignancies (e.g. kidney, non-Hodgkin lymphoma) is inconclusive, whereas prostatic cancer occurs less frequently in male patients with diabetes. The potential biologic links between the two diseases are incompletely understood. Evidence from observational studies suggests that some medications used to treat hyperglycemia are associated with either increased or reduced risk of cancer. Whereas anti-diabetic drugs have a minor influence on cancer risk, drugs used to treat cancer may either cause diabetes or worsen pre-existing diabetes. If hyperinsulinemia acts as a critical link between the observed increased cancer risk and type 2 diabetes, one would predict that patients with type 1 diabetes would have a different cancer risk pattern than patients with type 2 diabetes because the former patients are exposed to lower levels of exogenous administered insulin. Obtained results showed that patients with type 1 diabetes had elevated risks of cancers of the stomach, cervix, and endometrium. Type 1 diabetes is associated with a modest excess cancer risk overall and risks of specific cancers that differ from those associated with type 2 diabetes.

Use of insulin and insulin analogs and risk of cancer - systematic review and meta-analysis of observational studies

Background:

An association of insulin use and risk of cancer has been reported but evidence is conflicting and methodological issues have been identified.

Objective:

To summarize results regarding insulin use and cancer risk by a systematic review and meta-analysis of cohort and case-control studies examining risk of cancer associated with insulin use in patients with diabetes.

Data Sources:

Systematic literature search in 5 databases: PubMed, Embase, Web of Science, Scopus and Cochrane Library.

Study Eligibility Criteria (PICOS):

Population: diabetes patients. Exposure: Users of any exogenous insulin. Comparison: Diabetes patients with or without use of antidiabetic drugs. Outcome: Any incident cancer. Study Design: Cohort and case-control studies.

Results:

42 eligible studies examined risk of any cancer and 27 site-specific cancers. Results of individual studies were heterogeneous. Meta-analyses were significant for: Insulin vs No Insulin: Increased risk for pancreas, liver, kidney, stomach and respiratory cancer, decreased risk for prostate cancer. Insulin vs Non-Insulin Antidiabetics: Increased risk for any, pancreatic and colorectal cancer. Glargine vs Non-Glargine Insulin: Increased risk for breast cancer, decreased risk for colon cancer.

Limitations:

Few studies available for most cancer sites and exposure contrasts, and few assess effect of dose and duration of exposure. Methodological issues in several studies. Availability of confounders.

Conclusions:

Insulin use was associated with risk of cancer at several sites. Cautious interpretation of results is warranted as methodological issues and limitations in several of the included studies have been identified. Choice of study design may have a profound effect on estimated cancer risk.

Comparative efficacy and safety of long-acting insulin analogs in patients with type 2 diabetes failing on oral therapy: Systemic review and meta-analyses

Aims/Introduction:  Although long‐acting insulin analogs are recommended in type 2 diabetics failing on oral agents, their efficacy is uncertain. Here we compared the efficacy and safety of regimens based on long‐acting insulin analogs with other preparations in insulin‐naïve type 2 diabetics failing on oral agents.

Materials and Methods:  Data from 9548 participants in 22 English studies were included. Most of the studies were of short to medium duration and of low quality.

Results:  In terms of decreasing hemoglobin A1c, long‐acting insulin analogs were not statistically significant to rapid‐acting insulin analogs or intermediate neutral protamine Hagedorn (NPH) insulin or glucagon‐like peptide‐1 (GLP‐1) analogs, and the differences between long‐acting and biphasic insulin analogs were marginal. Compared with rapid‐acting insulin analogs, long‐acting insulin analogs were similar in the incidence of total hypoglycemia, and the superiority in less weight gain was inconsistent. Relative to biphasic insulin analogs, long‐acting insulin analogs were associated with lower incidence of total hypoglycemia and less weight gain. Compared with NPH insulin, long‐acting insulin analogs were associated with lower incidence of total and nocturnal hypoglycemia. Relative to GLP‐1 analogs, long‐acting insulin analogs were associated with lower incidence of treatment related adverse events but with greater weight gain.

Conclusions:  For type 2 diabetics failing on oral agents, initiating long‐acting insulin analogues seems to provide glycemic control similar to rapid‐acting insulin analogs or NPH insulin or glucagon‐like peptide‐1 analogs and slightly inferior to biphasic insulin analogs with fewer side‐effects. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00187.x, 2011)

Insulin degludec and insulin degludec/insulin aspart: a review of their use in the management of diabetes mellitus

Insulin degludec (Tresiba(®)) is an ultra-long-acting insulin analogue that is also available as a coformulation with rapid-acting insulin aspart (insulin degludec/insulin aspart) [Ryzodeg(®)]. Insulin degludec has a flat, stable glucose-lowering profile with a duration of action of >42 h, and less within-patient day-to-day variability in glucose-lowering effect than the long-acting insulin analogue insulin glargine. In clinical trials, insulin degludec achieved similar glycaemic control to that seen with insulin glargine in patients with type 1 or 2 diabetes, but with a lower risk of nocturnal hypoglycaemia. In addition, trials examining a flexible dosing regimen of insulin degludec in patients with type 1 or 2 diabetes show the potential for adjusting the injection time, without compromising glycaemic control or safety. A 200 U/mL formulation of insulin degludec is also available for use in patients who require large volumes of basal insulin. Insulin degludec/insulin aspart was noninferior to the long-acting insulin analogue insulin detemir in patients with type 1 diabetes and has the potential to reduce the number of daily injections. Trial results also indicate that insulin degludec/insulin aspart may be an appropriate option for initiating insulin therapy in patients with type 2 diabetes inadequately controlled with oral antidiabetic drugs. Subcutaneous insulin degludec was generally well tolerated in patients with type 1 or 2 diabetes. In conclusion, insulin degludec and insulin degludec/insulin aspart represent a useful advance in the treatment of type 1 or 2 diabetes.

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

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

Potential increased risk of cancer from commonly used medications: an umbrella review of meta-analyses

Several commonly used medications have been associated with increased cancer risk in the literature. Here, we evaluated the strength and consistency of these claims in published meta-analyses. We carried out an umbrella review of 74 meta-analysis articles addressing the association of commonly used medications (antidiabetics, antihyperlipidemics, antihypertensives, antirheumatics, drugs for osteoporosis, and others) with cancer risk where at least one meta-analysis in the medication class included some data from randomized trials. Overall, 51 articles found no statistically significant differences, 13 found some decreased cancer risk, and 11 found some increased risk (one reported both increased and decreased risks). The 11 meta-analyses that found some increased risks reported 16 increased risk estimates, of which 5 pertained to overall cancer and 11 to site-specific cancer. Six of the 16 estimates were derived from randomized trials and 10 from observational data. Estimates of increased risk were strongly inversely correlated with the amount of evidence (number of cancer cases) (Spearman's correlation coefficient = -0.77, P < 0.001). In 4 of the 16 topics, another meta-analysis existed that was larger (n = 2) or included better controlled data (n = 2) and in all 4 cases there was no statistically significantly increased risk of malignancy. No medication or class had substantial and consistent evidence for increased risk of malignancy. However, for most medications we cannot exclude small risks or risks in population subsets. Such risks are unlikely to be possible to document robustly unless very large, collaborative studies with standardized analyses and no selective reporting are carried out.

Diabetes and cancer: a 2013 synopsis

Diabetes, in particular type 2 diabetes, and cancer are two diseases that appear to be associated. Numerous epidemiological studies indicate indeed that diabetes increases the incidence of several tumors. Chronic hyperglycemia and/or insulin resistance with compensatory hyperinsulinemia could account for the association. On the other hand, the interpretation of the link between diabetes and cancer could be influenced by therapeutical interferences. Considering all these data together, cancer should be considered as a "new potential complication" of diabetes and integrated in the follow-up of diabetic subjects.

Diabetes treatments and cancer risk: the importance of considering aspects of drug exposure

Investigations of the association between diabetes, diabetes treatments, and cancer risk have raised several epidemiological challenges. In particular, a patient's exposure to glucose-lowering drugs needs to be represented accurately to allow unbiased assessment of the link between the treatments and cancer risk. Many studies have used a simple binary contrast (exposure to a specific drug vs no exposure), which has potentially serious drawbacks. In addition, methods used to determine the duration and cumulative dose of drug exposure differ widely between studies. In this Review, we discuss representation of drug exposure in pharmacoepidemiological investigations of the connection between diabetes drugs and cancer risk. We identify principles that might improve future research (particularly in observational studies), and consider issues related to reverse causation and detection bias.

Insulin detemir: a review of its use in the management of diabetes mellitus

Insulin detemir (Levemir®) is a long-acting insulin analogue indicated for use as basal insulin therapy in patients with type 1 or 2 diabetes mellitus. The protracted action of insulin detemir is explained by increased self-association and reversible binding to albumin, which slows its systemic absorption from the injection site. In glucose-clamp studies, less within-patient variability in glucose-lowering effect was seen with insulin detemir than with neutral protamine Hagedorn (NPH) insulin or insulin glargine in patients with type 1 or 2 diabetes. The beneficial effect of insulin detemir on glycaemic control was shown in numerous randomized, open-label, multicentre trials, including when used as basal-bolus therapy in patients with type 1 or 2 diabetes and as basal therapy in addition to oral antidiabetic drugs in insulin-naive patients with type 2 diabetes. In terms of glycosylated haemoglobin (HbA(1c)).[primary endpoint in most trials], insulin detemir was generally at least as effective as NPH insulin, insulin glargine or insulin lispro protamine suspension in patients with type 1 or 2 diabetes, and at least as effective as biphasic insulin aspart in patients with type 2 diabetes. Less within-patient variability in blood glucose was also generally seen with insulin detemir than with NPH insulin in patients with type 1 or 2 diabetes. Significantly less weight gain was generally seen with insulin detemir than with NPH insulin in patients with type 1 diabetes or with insulin detemir than with NPH insulin, insulin glargine, insulin lispro protamine suspension or biphasic insulin aspart (in one study) in patients with type 2 diabetes (i.e. insulin detemir generally had a weight-sparing effect). The addition of insulin detemir to liraglutide plus metformin improved glycaemic control in insulin-naive patients with type 2 diabetes and inadequate glycaemic control, although a significantly greater reduction in bodyweight was seen in patients receiving liraglutide plus metformin than in those receiving add-on therapy with insulin detemir. Results of two trials in patients aged 2-16 or 6-17 years (and a subgroup analysis in children aged 2-5 years) indicate that a basal-bolus insulin regimen incorporating insulin detemir appears to be a suitable option for use in paediatric patients with type 1 diabetes. Less within-patient variation in self-measured fasting plasma glucose was seen with insulin detemir than with NPH insulin in one of the studies. Insulin detemir was noninferior to NPH insulin in pregnant women with type 1 diabetes in terms of the HbA(1c) value achieved at 36 gestational weeks. In addition, maternal and neonatal outcomes with insulin detemir were similar to those seen with NPH insulin. Subcutaneous insulin detemir was generally well tolerated in the treatment of patients with type 1 or 2 diabetes, including in paediatric patients and pregnant women with type 1 diabetes. The majority of adverse events, including serious adverse events, reported in insulin detemir recipients were not considered to be related to the study drug. Insulin detemir was generally associated with a significantly lower risk of nocturnal hypoglycaemia than NPH insulin in patients with type 1 or 2 diabetes, particularly nocturnal minor hypoglycaemia. In conclusion, insulin detemir is a useful option for use as basal insulin therapy in patients with type 1 or 2 diabetes.

Diabetes and pancreatic cancer

The relationship between diabetes and pancreatic cancer is complex. Diabetes or impaired glucose tolerance is present in more than 2/3rd of pancreatic cancer patients. Epidemiological studies have consistently shown a modest increase in the risk of pancreatic cancer in type 2 diabetes, with an inverse relationship to duration of disease. Additionally, recent studies suggest that anti-diabetic medications may modulate the risk of pancreatic cancer in type 2 diabetes. Subjects >50 years of age with new onset diabetes are at higher risk of having pancreatic cancer. However, to screen new-onset diabetes for pancreatic cancer, additional markers are needed that can distinguish pancreatic cancer-associated diabetes from type 2 diabetes.

Reporting of meta-analyses of randomized controlled trials with a focus on drug safety: An empirical assessment

Background

Due to the sparse nature of serious drug-related adverse events (AEs), meta-analyses combining data from several randomized controlled trials (RCTs) to evaluate drug safety issues are increasingly being conducted and published, influencing clinical and regulatory decision making. Evaluation of meta-analyses involves the assessment of both the individual constituent trials and the approaches used to combine them. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting framework is designed to enhance the reporting of systematic reviews and meta-analyses. However, PRISMA may not cover all critical elements useful in the evaluation of meta-analyses with a focus on drug safety particularly in the regulatory-public health setting.

Purpose

This work was conducted to (1) evaluate the adherence of a sample of published drug safety–focused meta-analyses to the PRISMA reporting framework, (2) identify gaps in this framework based on key aspects pertinent to drug safety, and (3) stimulate the development and validation of a more comprehensive reporting tool that incorporates elements unique to drug safety evaluation.

Methods

We selected a sample of meta-analyses of RCTs based on review of abstracts from high-impact journals as well as top medical specialty journals between 2009 and 2011. We developed a preliminary reporting framework based on PRISMA with specific additional reporting elements critical for the evaluation of drug safety meta-analyses of RCTs. The reporting of pertinent elements in each meta-analysis was reviewed independently by two authors; discrepancies in the independent evaluations were resolved through discussions between the two authors.

Results

A total of 27 meta-analyses, 12 from highest impact journals, 13 from specialty medical journals, and 2 from Cochrane reviews, were identified and evaluated. The great majority (>85%) of PRISMA elements were addressed in more than half of the meta-analyses reviewed. However, the majority of meta-analyses (>60%) did not address most (>80%) of the additional reporting elements critical for the evaluation of drug safety. Some of these elements were not addressed in any of the reviewed meta-analyses.

Limitations

This review included a sample of meta-analyses, with a focus on drug safety, recently published in high-impact journals; therefore, we may have underestimated the extent of the reporting problem across all meta-analyses of drug safety. Furthermore, temporal trends in reporting could not be evaluated in this review because of the short time interval selected.

Conclusions

While the majority of PRISMA elements were addressed by most studies reviewed, the majority of studies did not address most of the additional safety-related elements. These findings highlight the need for the development and validation of a drug safety reporting framework and the importance of the current initiative by the Council for International Organizations of Medical Sciences (CIOMS) to create a guidance document for drug safety information synthesis/meta-analysis, which may improve reporting, conduct, and evaluation of meta-analyses of drug safety and inform clinical and regulatory decision making.

Glargine safety, diabetes and cancer

INTRODUCTION

In 2009, several epidemiological studies suggested a higher frequency of malignancy in insulin glargine -treated patients. A number of follow-up epidemiological population studies as well as two randomized, controlled clinical studies, one a 5000-patient retinopathy study and the other a 12,000-patient cardiovascular outcomes trial (ORIGIN), found no higher frequency of malignancy in glargine-treated patients.

AREAS COVERED

We reviewed the existing literature as well as U.S. FDA records to investigate the association of cancer, diabetes, and insulin. There is a 20 - 40% higher incidence of malignancy in type 2 diabetes patients. Certain cancers are more common, including hepatocellular and pancreatic carcinoma, colorectal cancer, renal cancer, and breast and endometrial cancer, and non-Hodgkin's lymphoma. There are numerous inter-related factors which may promote both diabetes and malignancy, including dietary patterns, obesity, insulin resistance, and alcoholism. Patients who receive insulin treatment are typically older and "sicker" than those who receive oral agents.

EXPERT OPINION

It is very difficult to prove causal associations between diabetes and cancer due to the host of confounding factors. The hypothesis that hyperinsulinemia and IGF-1 receptor activation promote cancer is strong, but confounded by the association of hyperinsulinemia with obesity, which separately promotes malignancy. Although statistical techniques to adjust for confounding variables can improve epidemiological comparisons, the lesson of the glargine cancer controversy is that controlled clinical trials are the only means to definitely prove hypotheses.

The metabolic and mitogenic properties of basal insulin analogues

CONTEXT

Retrospective, observational studies have reported an association between diabetes treatment with insulin and a higher incidence of cancer.

OBJECTIVE

Overview the literature for in vitro and in vivo studies of the metabolic and mitogenic properties of basal insulin analogues and assess the implications for clinical use.

METHODS

Relevant studies were identified through PubMed and congress abstract database searches; data on metabolic and mitogenic signalling in relation to insulin treatment of diabetes are included in this review.

RESULTS

The balance of evidence shows that although some analogues have demonstrated mitogenic potency in some in vitro studies in cancer cell lines, these findings do not translate to the in vivo setting in animals or to the clinical setting in humans.

CONCLUSIONS

The current consensus is that there is no clinical or in vivo evidence to indicate that any commercially available insulin analogue has carcinogenic effects. Large-scale, prospective clinical and observational studies will further establish any potential link.

Cancer risk for patients using thiazolidinediones for type 2 diabetes: a meta-analysis

OBJECTIVE

To clarify and quantify the effect of thiazolidinediones (TZDs; e.g., pioglitazone, rosiglitazone) on the risk of bladder cancer, other selected cancers, and overall cancer in patients with type 2 diabetes, we performed a systematic review and meta-analysis of observational studies.

METHODS

A PubMed/MEDLINE search was conducted for studies published in English up to June 30, 2012. Random-effect models were fitted to estimate summary relative risks (RR).

RESULTS

Seventeen studies satisfying inclusion criteria (3 case-control studies and 14 cohort studies) were considered. Use of TZDs was not associated to the risk of cancer overall (summary RR: 0.96; 95% confidence interval [CI]: 0.91-1.01). A modest excess risk of bladder cancer was reported in pioglitazone (RR: 1.20; 95% CI: 1.07-1.34 from six studies) but not in rosiglitazone (RR: 1.08; 95% CI: 0.95-1.23 from three studies) users. The RRs of bladder cancer were higher for longer duration (RR: 1.42 for >2 years) and higher cumulative dose of pioglitazone (RR: 1.64 for >28,000 mg). Inverse relations were observed with colorectal cancer (RR: 0.93; 95% CI: 0.90-0.97 from six cohort studies) and liver cancer (RR: 0.65; 95% CI: 0.48-0.89 from four studies), whereas there was no association with pancreatic, lung, breast, and prostate cancers.

CONCLUSIONS

Adequate evidence excludes an overall excess cancer risk in TZD users within a few years after starting treatment. However, there is a modest excess risk of bladder cancer, particularly with reference to pioglitazone. Assuming that this association is real, the potential implications on the risk-benefit analysis of TZD use should be evaluated.

Insulin glargine and cancer risk in patients with diabetes: a meta-analysis

AIM

The role of insulin glargine as a risk factor for cancer is controversial in human studies. The aim of this meta-analysis was to evaluate the relationship between insulin glargine and cancer incidence.

METHODS

All observational studies and randomized controlled trials evaluating the relationship of insulin glargine and cancer risk were identified in PubMed, Embase, Web of Science, Cochrane Library and the Chinese Biomedical Medical Literature Database, through March 2012. Odds ratios (ORs) with corresponding 95% confidence interval (CI) were calculated with a random-effects model. Confidence in the estimates of the obtained effects (quality of evidence) was assessed by using the Grading of Recommendations Assessment, Development, and Evaluation approach.

RESULTS

A total of 11 studies including 448,928 study subjects and 19,128 cancer patients were finally identified for the meta-analysis. Insulin glargine use was associated with a lower odds of cancer compared with non-glargine insulin use (OR 0.81, 95% CI 0.68 to 0.98, P = 0.03; very low-quality evidence). Glargine did not increase the odds of breast cancer (OR 0.99, 95% CI 0.68 to 1.46, P = 0.966; very low-quality evidence). Compared with non-glargine insulin, no significant association was found between insulin glargine and prostate cancer, pancreatic cancer and respiratory tract cancer. Insulin glargine use was associated with lower odds of other site-specific cancer.

CONCLUSIONS

Results from the meta-analysis don't support the link between insulin glargine and an increased risk of cancer and the confidence in the estimates of the effects is very low. Further studies are needed to examine the relation between insulin glargine and cancer risk, especially breast cancer.

Insulin use and cancer risk in patients with type 2 diabetes: a systematic review and meta-analysis of observational studies

AIMS

To determine whether data from observational studies supports the hypothesis of an increased risk of overall and site-specific cancer among individuals with diabetes using exogenous insulin therapies.

METHODS

We conducted a comprehensive search of nine key biomedical databases for all years up to December 2011, restricted to the English language. Data from cohort and nested case-control studies were included in random effects meta-analyses of site-specific and overall cancer incidence comparing ever use and new use of: (1) insulin to no insulin and; (2) insulin glargine to other insulins.

RESULTS

The search yielded 3052 unique citations, of which 19 were selected for inclusion, representing data for 1,332,120 people and 41,947 cancers. Pancreatic cancer risk was increased among new users of insulin (RR: 3.18, 95%CI: 3.27-3.71, I(2)=32%). New use of insulin glargine was associated with an increased risk of pancreatic cancer (RR: 1.63, 95%CI: 1.05-2.51, I(2)=0%) and prostate cancers (RR: 2.68, 95%CI: 1.50-4.79, I(2)=0%) but a decreased risk of colorectal cancer (RR: 0.78, 95%CI: 0.64-0.94, I(2)=15%).

CONCLUSION

New use of insulin or insulin glargine was associated with an increased risk of pancreatic cancer, possibly due to reverse causality. New use of insulin glargine was associated with a decreased risk of colorectal cancer but an increased risk of prostate cancer. Our results should be interpreted with caution due to limitations of included studies.

Insulin therapy and cancer in type 2 diabetes

Despite the availability of many other agents, insulin is widely used as a treatment for type 2 diabetes. In vitro, insulin stimulates the growth of cancer cells, through the interaction with insulin-like growth factor-1 (IGF-1) receptors and its own receptors. In observational surveys on type 2 diabetes, insulin therapy is associated with an increased incidence of several forms of cancer, although it is difficult to discriminate the effect of confounders from that of insulin itself. Randomized trials do not confirm the increased risk associated with insulin therapy, although they do not allow to rule out some negative effects on specific forms of cancer, at least at higher doses. Among insulin analogues, glargine has a higher affinity for the IGF-1 receptor and a greater mitogenic potency in vitro than human insulin, but it is extensively metabolized in vitro to products with low IGF-1 receptor affinity. Overall, epidemiological studies suggest a possible increase of risk with glargine, with respect to human insulin, only at high doses and for some forms of cancer (i.e., breast). Data from clinical trials do not confirm, but are still insufficient to totally exclude, such increased risk. However, beneficial effects of insulin outweigh potential cancer risks.

Long-acting basal insulin analogs: latest developments and clinical usefulness

All patients with type 1 diabetes mellitus need insulin treatment permanently, and many patients with type 2 diabetes will require insulin therapy. Basal insulin analogs are increasingly used in the treatment of diabetes, with the aim of offering a better replication of the pattern of basal endogenous secretion of insulin. Their flatter pharmacodynamic profile, with a much lower peak of action, their slow and continuous absorption into the systemic circulation, and prolonged duration, more closely duplicate the endogenous insulin secretion leading to physiological basal glycemic control and affording more flexible treatment with fewer hypoglycemia episodes. The basal analogs represent the most significant advances in 'basal insulin' supplementation, and can be used in different insulin regimens achieving the same clinical effectiveness over conventional insulins, with benefits in terms of hypoglycemia and less weight gain, and may be an option for patients with problematic hypoglycemia despite optimization of conventional insulin therapy. At present, there are no data on micro- or macrovascular endpoints, and indeed it is unlikely that these will become available, at least in the foreseeable future. The evidence for basal insulin analogs affecting the risk of cancer is limited, and overriding diabetes indications rather than putative cancer concerns should remain the principal consideration when selecting therapy in patients with diabetes.

Insulin glargine and risk of cancer: a meta-analysis

AIMS

Recently, more and more attention has been drawn on the long-term effects of insulin glargine. Here we strived to estimate the association of cancer occurrence with the use of insulin glargine.

METHODS

We searched all the publications regarding the association between cancer occurrence and the use of insulin glargine using the US National Library of Medicine's PubMed database. Data were independently extracted and analyzed using random or fixed effects meta-analysis depending upon the degree of heterogeneity.

RESULTS

Seven cohort studies were included in the meta-analysis. Cancer occurrence had no significant difference in glargine-treated patients compared to patients treated with other insulins (RR=0.86, 95% CI=0.69-1.07, p=0.17, P(heterogeneity)<0.00001). In our subgroup analysis, glargine, compared to other insulins, did not increase the risk of breast cancer (RR=1.14, 95% CI=0.65-2.02, p=0.65, P(heterogeneity)=0.002), prostate cancer (RR=1.00, 95% CI=0.79-1.26, p=0.99, P(heterogeneity)=0.78), pancreatic cancer (RR=0.57, 95% CI=0.14-2.35, p=0.44, P(heterogeneity)=0.0002) and gastrointestinal cancer (RR=0.80, 95% CI=0.62-1.02, p=0.07, P(heterogeneity)=0.86).

CONCLUSIONS

This meta-analysis of open-label studies does not support an increased cancer risk in patients treated with insulin glargine. The result provides confidence for the development of insulin glargine, but needs confirmation by further clinical studies.

Diabetes, glucose control, glucose lowering medications, and cancer risk: a 10-year population-based historical cohort

Background

Both diabetes and glucose-lowering medications have been associated with an increased risk of cancer incidence. This study will compare cancer incidence rates in individuals with and without diabetes; and will investigate, in individuals with diabetes, an association between glucose control and cancer incidence; and between the use of specific glucose-lowering medications, as well as no drug exposure, and cancer incidence.

Methods/design

This is a population based historical cohort study of all individuals aged 21 years or older (about 2,300,000) who were insured by Clalit Health Services, the largest health maintenance organization in Israel during a ten-year study period. Four study groups will be established according to the status of diabetes and cancer at study entry, Jan 1, 2002: cancer free, diabetes free; cancer free, diabetes prevalent; cancer prevalent, diabetes free; and cancer prevalent, diabetes prevalent. Individuals without diabetes at study entry will be followed for diabetes incidence, and all four groups will be followed for specific cancer incidence, including second primary neoplasms. Glucose control will be assessed by HbA1c and by fasting plasma glucose levels. Time dependent regression models for cancer incidence will account for glucose-lowering medications as they are added and changed over the follow-up period. A large number of demographic and clinical variables will be considered, including: age, gender, BMI, smoking status, concomitant medications, glucose control (assessed by HbA1c and by fasting plasma glucose) and cancer screening tests.

Discussion

Strengths of this study include the large population; high quality comprehensive data; comparison to individuals without diabetes, and to those with diabetes but not treated with glucose-lowering medications; and the extensive range of variables available for analysis. The great increases in diabetes prevalence and in treatment options render this study particularly relevant and timely. The Israeli national healthcare system, characterized by high standard and uniform healthcare, offers an advantageous environment for its conduct.

Epidemiological evidence of a relationship between type-1 diabetes mellitus and cancer: a review of the existing literature

This review explores the epidemiological evidence relating to type-1 diabetes (T1DM) and cancer incidence and mortality. Mortality rates among those with T1DM are higher in every age group compared with the general population; the majority of this mortality is due to factors related to the consequences of diabetes, such as cardiovascular and renal disease. For over 100 years, researchers have explored the relationships between diabetes and cancer and although there is now a large body of work on the subject, consensus has not been reached. Such research has tended to focus upon type-2 diabetes, with the result that very little is known about T1DM and cancer. As incidence of T1DM increases, by around 3% annually among children, the need for further research into its impact upon cancer incidence and mortality increases. Within this review, findings varied by study method utilised, T1DM definition used and study region and outcome measure explored. None of the case-control studies found a statistically significant link between the two diseases, whereas both of the meta-analyses did. Cohort studies produced mixed results. There were also mixed findings among research that defined T1DM in the same way (e.g. defining individuals with the disease as those diagnosed with diabetes before 30 years of age). The review found a number of studies which explored cause-specific cancer mortality among those with diabetes; such studies also had mixed findings. This inconsistency within results suggests the need for further research to understand better the potential relationships between T1DM and cancer.

Insulin degludec as an ultralong-acting basal insulin once a day: a systematic review

BACKGROUND

Insulin degludec (IDeg) is a neutral, ultralong-acting new generation basal insulin analog developed by NovoNordisk currently in Phase III clinical development. IDeg offers a duration of action of more than 42 hours in adults, much longer than current basal insulin formulations.

OBJECTIVE

The aim of this review is to assess the efficacy and safety data of IDeg in the treatment of type 1 and type 2 diabetes mellitus.

METHODS

Relevant English language articles from 2010 to 2012 were identified through MEDLINE, PubMed, EMBASE, Scopus, BIOSIS, and Google Scholar. Online conference proceedings of the 71st ADA Scientific Sessions and the 47th EASD Annual Meeting were reviewed. Studies were compared in terms of their study designs, primary and secondary efficacy parameters, and tolerability data.

RESULTS

There are a total of nine published trials investigating the clinical efficacy and safety of IDeg in over 3000 subjects with type 1 and 2 diabetes. Only three trials were published in full. All were open-label, randomized multicenter trials with durations of 16 to 52 weeks. IDeg and coformulations of IDeg with insulin aspart (IAsp) were compared to insulin glargine (IGlar), detemir, and biphasic IAsp 30 (BIAsp 30).

CONCLUSION

Based upon the available evidence, there appear to be no reported differences between IDeg and IGlar, detemir, or BIAsp 30 in the reduction of the primary efficacy end-points of HbA(1c) and mean fasting plasma glucose (FPG) concentrations. Only flexible dosing of IDeg provided a significant reduction in FPG compared to IGlar. IDeg demonstrated a significant reduction in nocturnal hypoglycemia in type 1 diabetes. In type 2 diabetes, IDeg reduced the incidence of hypoglycemia by 18% and 58% compared to IGlar and BIAsp 30, respectively.

Diabetes and cancer II: role of diabetes medications and influence of shared risk factors

An association between type 2 diabetes mellitus (DM) and cancer has long been postulated, but the biological mechanism responsible for this association has not been defined. In part one of this review, we discussed the epidemiological evidence for increased risk of cancer, decreased cancer survival, and decreased rates of cancer screening in diabetic patients. Here we review the risk factors shared by cancer and DM and how DM medications play a role in altering cancer risk. Hyperinsulinemia stands out as a major factor contributing to the association between DM and cancer, and modulation of circulating insulin levels by DM medications appears to play an important role in altering cancer risk. Drugs that increase circulating insulin, including exogenous insulin, insulin analogs, and insulin secretagogues, are generally associated with an increased cancer risk. In contrast, drugs that regulate insulin signaling without increasing levels, especially metformin, appear to be associated with a decreased cancer risk. In addition to hyperinsulinemia, the effect of DM medications on other shared risk factors including hyperglycemia, obesity, and oxidative stress as well as demographic factors that may influence the use of certain DM drugs in different populations are described. Further elucidation of the mechanisms behind the association between DM, cancer, and the role of DM medications in modulating cancer risk may aid in the development of better prevention and treatment options for both DM and cancer. Additionally, incorporation of DM medication use into cancer prediction models may lead to the development of improved risk assessment tools for diabetic patients.

Diabetes and cancer (1): evaluating the temporal relationship between type 2 diabetes and cancer incidence

Substantial evidence suggests that people with type 2 diabetes have an increased risk of developing several types of cancers. These associations may be due to a number of direct and indirect mechanisms. Observational studies of these associations, including the potential role for glucose-lowering therapy, are being increasingly reported, but face a number of methodological challenges. This paper is the first of two review papers addressing methodological aspects underpinning the interpretations of links between diabetes and cancer, and suggests potential approaches to study designs to be considered in observational studies. This paper reviews factors related to cancer incidence in the diabetic population; the second paper relates to studies of cancer mortality.