Metabolic Control in Type 1 Diabetes: Is Adjunctive Therapy the Way Forward?

Unmet needs in the treatment of type 1 diabetes: why is it so difficult to achieve an improvement in metabolic control?

The development of advanced diabetes technology has permitted persons with type 1 diabetes mellitus to improve metabolic control significantly, particularly with the development of advanced hybrid closed-loop systems which have improved the quality of life by reducing hypoglycemia, decreasing macroangiopathy and microangiopathy-related complications, ameliorating HbA1c and improving glycemic variability. Despite the progression made over the past few decades, there is still significant margin for improvement to be made in terms of attaining appropriate metabolic control. Various factors are responsible for poor glycemic control including inappropriate carbohydrate counting, repeated bouts of hypoglycemia, hypoglycemia unawareness, cutaneous manifestations due to localized insulin use and prolonged use of diabetes technology, psychosocial comorbidities such as eating disorders or 'diabulimia', the coexistence of insulin resistance among people with type 1 diabetes and the inability to mirror physiological endogenous pancreatic insulin secretion appropriately. Hence, the aim of this review is to highlight and overcome the barriers in attaining appropriate metabolic control among people with type 1 diabetes by driving research into adjunctive treatment for coexistent insulin resistance and developing new advanced diabetic technologies to preserve β cell function and mirror as much as possible endogenous pancreatic functions.

Progression of insulin resistance in individuals with type 1 diabetes: A retrospective longitudinal study on individuals from Thailand

AIMS

To investigate temporal changes in glycaemic control and weight contributing to insulin resistance (IR), in Thai individuals with type 1 diabetes (T1D).

METHODS

Longitudinal data of 69 individuals with T1D were retrospectively collected over a median follow-up of 7.2 years. The estimated glucose disposal rate (eGDR), a marker of IR, was calculated using an established formula. Individuals were assigned as insulin-sensitive T1D (the latest eGDR≥8 mg/kg/min), or insulin-resistant T1D/double diabetes (the latest eGDR<8 mg/kg/min). Generalised linear mixed model was employed to compare the temporal patterns of HbA1c, BMI, and eGDR between the two groups.

RESULTS

26 insulin-resistant T1D had a gradual decline in eGDR, corresponding with increased weight and HbA1c. In contrast, 43 insulin-sensitive T1D had stable insulin sensitivity with an improvement in HbA1c over time, associated with a modest weight gain. Fluctuations of glucose levels were observed during the early diabetes course leading to unstable eGDR, thus limiting the use of eGDR to classify insulin-resistant T1D.

CONCLUSION

T1D individuals who eventually develop IR are likely to experience early increasing IR over time. In contrast, those who ultimately do not have IR, maintain their insulin sensitivity throughout their course at least in the medium term.

An exploration of the experience of dapagliflozin in clinical practice

Despite the availability of established treatments, heart failure (HF) is associated with a poor prognosis and suboptimal management, highlighting the need for new treatment and prevention options. It is suggested that sodium-glucose cotransporters 2 inhibitors can provide a beneficial therapeutic approach to significantly lower the disease burden associated with cardiovascular illness in both patients with and without Type 2 diabetes mellitus. This review focuses on the therapeutic aspects of dapagliflozin in clinical practice. Future studies may intend to confirm the significant clinical benefits of sodium-glucose cotransporter-2 inhibitors.

Cardiovascular Disease in Adults with Type 1 Diabetes: Looking Beyond Glycemic Control

PURPOSE OF REVIEW

Despite improvements in treatment, people with type 1 diabetes continue to have increased cardiovascular disease (CVD) risk. Glycemic control does not fully explain this excess CVD risk, so a greater understanding of other risk factors is needed.

RECENT FINDINGS

The authors review the relationship between glycemia and CVD risk in adults with type 1 diabetes and summarize evidence regarding other factors that may explain risk beyond glycemia. Insulin resistance, weight gain, sex differences, genetics, inflammation, emerging markers of risk, including lipid subclasses and epigenetic modifications, and future directions are discussed. As glycemic control improves, an increased focus on other CVD risk factors is warranted in type 1 diabetes. Novel markers and precision medicine approaches may improve CVD prediction, but a lack of type 1 diabetes-specific guidelines for lipids, blood pressure, and physical activity are likely impediments to optimal CVD prevention in this high-risk population.

Metabolic syndrome associated with higher glycemic variability in type 1 diabetes: A multicenter cross-sectional study in china

AIMS

The comorbidity of metabolic syndrome (MetS) and type 1 diabetes mellitus (T1DM) is an obstacle to glucose control in patients with T1DM. We compared glycemic profiles using continuous glucose monitoring (CGM) systems in patients with T1DM with or without MetS.

METHODS

This was a multicenter cross-sectional study of patients with T1DM (N = 207) with or without MetS. CGM data were collected from study enrollment until discharge during a 1-week study session. We analyzed baseline HbA1c, average glucose, estimated HbA1c, time in range (TIR), time above range (TAR), time below range (TBR), coefficient of variation (CV), postprandial glucose excursions (PPGE) and other glycemic variability (GV) metrics. Logistic regression was developed to investigate the association between MetS and CGM metrics.

RESULTS

The results showed higher average baseline HbA1c levels, and a higher percentage of patients with baseline HbA1c levels ≥7.5%, in the T1DM with MetS group. Furthermore, MetS was associated with GV, which indicated a higher CV in patients with T1DM with MetS. However, our results showed that TAR, TIR, TBR and other GV metrics were comparable between the two groups. The T1DM with MetS group also had a higher proportion of patients with high CV (≥ 36%) than the group without MetS. In multivariable logistic regression analysis, the presence of MetS was a risk factor for high CV (≥ 36%) in our study participants.

CONCLUSIONS

T1DM patients with MetS in our study had better β-cell function. However, MetS was associated with worse glycemic control characterized by higher GV and HbA1c levels. Efforts should be expanded to improve treatment of MetS in patients with T1DM to achieve better glycemic control.

One hundred years of insulin therapy

At the time of its first clinical application 100 years ago, insulin was presented as the cure for people with diabetes mellitus. That transpired to be an overstatement, yet insulin has proven to be the lifesaver for people with type 1 diabetes mellitus and an essential therapy for many with type 2 diabetes mellitus or other forms of diabetes mellitus. Since its discovery, insulin (a molecule of only 51 amino acids) has been the subject of pharmaceutical research and development that has paved the way for other protein-based therapies. From purified animal-extracted insulin and human insulin produced by genetically modified organisms to a spectrum of insulin analogues, pharmaceutical laboratories have strived to tailor the preparations to the needs of patients. Nonetheless, overall glycaemic control often remains poor as exogenous insulin is still not able to mimic the physiological insulin profile. Circumventing subcutaneous administration and the design of analogues with profiles that mimic that of physiological insulin are ongoing areas of research. Novel concepts, such as once-weekly insulins or glucose-dependent and oral insulins, are on the horizon but their real-world effectiveness still needs to be proven. Until a true cure for type 1 diabetes mellitus is found and the therapeutic arsenal for other forms of diabetes mellitus is expanded, insulin will remain central in the treatment of many people living with diabetes mellitus.

Sexual Dimorphism in Alternative Metabolic Pathways of L-Arginine in Circulating Leukocytes in Young People with Type 1 Diabetes Mellitus

Background: Sexual dimorphism in specific biochemical pathways and immune response, underlies the heterogeneity of type 1 diabetes mellitus (T1DM) and affects the outcome of immunotherapy. Arginase and nitric oxide (NO) synthase (NOS) metabolize L-arginine and play opposite roles in the immune response and autoimmune processes.Objective: We hypothesized that the above mentioned enzymes can be involved in sex and age differences in T1DM and its treatment. Based on this, the enzymes have been studied in peripheral blood leukocytes (PBL) and plasma of young people with T1DM.Methods: Patients were recruited from Muratsan University Hospital (Yerevan, Armenia) and were divided into groups: girls and boys by age, from children to adolescents and adolescents/young adults with recent-onset T1DM (RO-T1DM) (0.1-1 years) and long-term T1DM (LT-T1DM) (1.6-9.9 years). Arginase activity was assessed by L-arginine-dependent production of L-ornithine, and the NOS activity was assessed by NO/nitrite production. Glycemic control was assessed using hemoglobin A1c test. Plasma HbA1c concentration below 7.5% (median (range) 6.7 [6.2-7.5]) was taken as good glycemic control (+) and above 7.5% (median (range) 10.5 [7.6-13]) as poor glycemic control (-). Healthy volunteers with corresponding sex and age were used as the control group.Results: All the patients with RO-T1DM, with poor glycemic control, had increased arginase activity in the cytoplasm (cARG) and mitochondria (mARG) in PBL. In girls with RO-T1DM, with good glycemic control, the subcellular arginase activity decreased, and normalized in LT-T1DM, regardless of age. In contrast, boys from both age groups showed high arginase activity, regardless of glycemic control and duration of T1DM along with insulin therapy. At the same time, a significant decrease in the subcellular production of bioavailable NO was observed in children/preadolescents, regardless of glycemic control and duration of diabetes. In adolescents/young adult boys with RO-T1DM, with (-), the subcellular production of NO decreased significantly, and with LT-T1DM, the decrease was attenuated, but even with (+) remained lower than in healthy people. In contrast, in the group of same age girls with RO-T1DM, NO production increased above normal in both cellular compartments, while with LT-T1DM it normalized in the cytoplasm. In adolescents/young adults with LT-T1DM, NO production in PBL mitochondria decreased by almost a half, regardless of glycemic control and gender. Changes in the metabolic pathways of L-arginine in plasma differed and were less substantial than in the PBL cellular compartments in T1DM.Conclusions: Glycemic status and duration of T1DM along with insulin therapy affect the activity of arginase and NOS-dependent production of bioavailable NO in the cytoplasm and mitochondria in PBL of young patients with T1DM, depending on sex and age. Arginase and NOS can directly affect the processes occurring in the pancreas and the outcome of therapy through infiltrated leukocytes. Obtained data can be useful for understanding the heterogeneity of T1DM and using it to develop available criteria for assessing the severity and treatment of autoimmune diabetes.

Intestinal Microbiota Play an Important Role in the Treatment of Type I Diabetes in Mice With BefA Protein

More and more studies have shown that the intestinal microbiota is the main factor in the pathogenesis of type 1 diabetes mellitus (T1DM). Beta cell expansion factor A (BefA) is a protein expressed by intestinal microorganisms. It has been proven to promote the proliferation of β-cells and has broad application prospects. However, as an intestinal protein, there have not been studies and reports on its application in diabetes and its mechanism of action. In this study, a T1DM model induced by multiple low-dose STZ (MLD-STZ) injections was established, and BefA protein was administered to explore its therapeutic effect in T1DM and the potential mechanism of intestinal microbiota. BefA protein significantly reduced the blood glucose, maintained the body weight, and improved the glucose tolerance of the mice. At the same time, the BefA protein significantly increased the expression of ZO-1, Occludin, and significantly reduced the expression of TLR-4, Myd88, and p-p65/p65. BefA protein significantly reduced the relative expression of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α. In addition, our high-throughput sequencing shows for the first time that the good hypoglycemic effect of BefA protein is strongly related to the increase in the abundance of the beneficial gut bacteria Lactobacillus, Bifidobacterium and Oscillospria and the decrease in the abundance of the opportunistic pathogen Acinetobacter. Our group used animal models to verify the hypoglycemic effect of BefA protein, and first explored the potential mechanism of intestinal microbiota in BefA protein treatment.

Selenium Deficiency Due to Diet, Pregnancy, Severe Illness, or COVID-19-A Preventable Trigger for Autoimmune Disease

The trace element selenium (Se) is an essential part of the human diet; moreover, increased health risks have been observed with Se deficiency. A sufficiently high Se status is a prerequisite for adequate immune response, and preventable endemic diseases are known from areas with Se deficiency. Biomarkers of Se status decline strongly in pregnancy, severe illness, or COVID-19, reaching critically low concentrations. Notably, these conditions are associated with an increased risk for autoimmune disease (AID). Positive effects on the immune system are observed with Se supplementation in pregnancy, autoimmune thyroid disease, and recovery from severe illness. However, some studies reported null results; the database is small, and randomized trials are sparse. The current need for research on the link between AID and Se deficiency is particularly obvious for rheumatoid arthritis and type 1 diabetes mellitus. Despite these gaps in knowledge, it seems timely to realize that severe Se deficiency may trigger AID in susceptible subjects. Improved dietary choices or supplemental Se are efficient ways to avoid severe Se deficiency, thereby decreasing AID risk and improving disease course. A personalized approach is needed in clinics and during therapy, while population-wide measures should be considered for areas with habitual low Se intake. Finland has been adding Se to its food chain for more than 35 years-a wise and commendable decision, according to today's knowledge. It is unfortunate that the health risks of Se deficiency are often neglected, while possible side effects of Se supplementation are exaggerated, leading to disregard for this safe and promising preventive and adjuvant treatment options. This is especially true in the follow-up situations of pregnancy, severe illness, or COVID-19, where massive Se deficiencies have developed and are associated with AID risk, long-lasting health impairments, and slow recovery.

Sodium-glucose cotransporter 2 inhibitors as an add-on therapy to insulin for type 1 diabetes mellitus: Meta-analysis of randomized controlled trials

AIMS

The aim was to systematically review the efficacy and safety of sodium-glucose cotransporter inhibitor (SGLT2i) as an adjunct to insulin at different follow-up durations in randomized, double-blind clinical trials in patients with type 1 diabetes.

METHODS

We conducted a search on Medline, Embase, and the Cochrane Library for relevant studies published before May 2020. According to the duration of follow-up, the subgroup analysis included four periods: 1-4, 12-18, 24-26, and 52 weeks. In the five trials included both 24-26 and 52 weeks of follow-up, we compared the efficacy by the placebo-subtracted difference and changes in SGLT2i groups.

RESULTS

Fifteen trials including 7109 participants were analyzed. The combination of SGLT2i and insulin improved hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), daily insulin dose, body weight, and blood pressure, which varied greatly by different follow-ups. Compared with %HbA1c at 24-26 weeks, placebo-subtracted differences and changes in the SGLT2i groups slightly increased. SGLT2i plus insulin treatment showed no difference in the occurrence of urinary tract infections (UTIs), hypoglycemia, or severe hypoglycemia but increased the risk of genital tract infections (GTIs) in a duration-dependent manner. SGLT2i treatment was associated with a significantly higher rate of ketone-related SAEs and diabetic ketoacidosis (DKA) at 52 weeks.

CONCLUSION

SGLT2i as an add-on therapy to insulin improved glycemic control and body weight and decreased the required dose of insulin without increasing the risk of hypoglycemia. However, after 6 months the benefits of SGLT2is on glycemic control may weaken and the risks of GTIs and DKA increased.

Using adjuvant pharmacotherapy in the treatment of type 1 diabetes

Introduction: Insulin and its analogues have so far been the only approved treatment for type 1 diabetes in Europe, while in the U.S. the amylin analog pramlintide is approved for adjuvant use with insulin. However, in clinical practice, various drugs against type 2 diabetes have been used off label with insulin for type 1 diabetes. Recently, the EMA approved the SGLT inhibitors dapagliflozin and sotagliflozin as adjuvant treatments to insulin for type 1 diabetes in adults.Areas covered: This article is a survey of adjuvant treatments used against type 1 diabetes, focusing on SGLT inhibitors.Expert opinion: While GLP-1R agonists and metformin may reduce weight gain associated with insulin therapy and possibly also confer non-glycemic benefits, only the SGLT inhibitors dapagliflozin and sotagliflozin have been approved in Europe as adjunctive to insulin for type 1 diabetes. Since these drugs act independently of insulin, they are very valuable additions to the armamentarium against type 1 diabetes. However, they should be used judiciously in select patients to mitigate the risk of diabetic ketoacidosis. Patients should be instructed to avoid risk situations and be taught to measure blood ketones themselves.

Body mass index, estimated glucose disposal rate and vascular complications in type 1 diabetes: Beyond glycated haemoglobin

AIMS

To understand the relationship between insulin resistance (IR), assessed as estimated glucose disposal rate (eGDR), and microvascular/macrovascular complications in people with type 1 diabetes.

MATERIALS AND METHODS

Individuals with a confirmed diagnosis of type 1 diabetes were included in this cross-sectional study. BMI was categorised into normal weight (18.0-24.9 kg m^-2 ), overweight (25.0-29.9 kg m^-2 ) and obese groups (≥30.0 kg m^-2 ). We categorised eGDR into four groups: eGDR >8, 6-7.9, 4-5.9 and <4 mg kg^-1  min^-1 . Multiple logistic regression was used to identify associations with vascular complications, after adjusting for relevant confounders.

RESULTS

A total of 2151 individuals with type 1 diabetes were studied. Median [interquartile range (IQR)] age was 41.0 [29.0, 55.0] with diabetes duration of 20.0 [11, 31] years. Odds ratio (OR) for retinopathy and nephropathy in obese compared with normal weight individuals was 1.64 (95% CI: 1.24-2.19; p = 0.001) and 1.62 (95% CI: 1.10-2.39; p = 0.015), while the association with cardiovascular disease just failed to reach statistical significance (OR 1.66 [95% CI: 0.97-2.86; p = 0.066]). Comparing individuals with eGDR ≥8 mg kg^-1  min^-1 and <4 mg kg^-1  min^-1 showed OR for retinopathy, nephropathy and macrovascular disease of 4.84 (95% CI: 3.36-6.97; p < 0.001), 8.35 (95% CI: 4.86-14.34; p < 0.001) and 13.22 (95% CI: 3.10-56.38; p < 0.001), respectively. Individuals with the highest eGDR category (≥8 mg kg^-1  min^-1 ) had the lowest complication rates irrespective of HbA_1c levels.

CONCLUSIONS

Obesity is prevalent in type 1 diabetes and diabetes complications are not only related to glucose control. IR, assessed as eGDR, is strongly associated with both microvascular and macrovascular complications, regardless of HbA_1c levels.

Insulin resistance-associated genetic variants in type 1 diabetes

AIMS

To examine candidate insulin resistance single nucleotide polymorphisms (SNPs) for associations with glycemic control, insulin resistance, BMI, and complications in an observational type 1 diabetes (T1D) cohort: the Pittsburgh Epidemiology of Diabetes Complications (EDC) study.

METHODS

In 422 European-ancestry participants, we assessed associations using additive models between 15 candidate SNPs and 25-year mortality, cardiovascular disease, microalbuminuria, overt nephropathy and proliferative retinopathy, and 25-year mean HbA1c, estimated glucose disposal rate (eGDR, inverse measure of insulin resistance), and BMI.

RESULTS

The A allele of rs12970134 was associated with higher mean HbA1c (β = +0.34 ± 0.09, p = 0.00009) and nominally associated with worse eGDR (p = 0.02). Further analyses suggest the HbA1c association may be modified by diabetes therapy regimen: rs12970134 AA genotype was associated with higher HbA1c under non-intensive therapy conditions (<3 insulin injections/day or monitoring blood glucose<3 times/day [p = 0.004]), but not under intensive therapy (≥3 injections/day or insulin pump and monitoring glucose≥3 times/day [p = 0.71]). There were no significant associations between any SNPs and BMI or complications.

CONCLUSIONS

rs12970134, near MC4R, is strongly associated with HbA1c in this cohort. Further exploration of this genomic region is warranted, as it may hold promise for discovering new therapeutic targets to improve glycemic control in T1D.

Therapeutic approaches for latent autoimmune diabetes in adults: One size does not fit all

Recent advances in the understanding of latent autoimmune diabetes in adults (LADA) pathophysiology make it increasingly evident that people with LADA comprise a heterogenous group of patients. This makes the establishment of a standard treatment algorithm challenging. On top of its glucose-lowering action, insulin may exert anti-inflammatory effects, rendering it an attractive therapeutic choice for a type of diabetes in which autoinflammation and beta cell insufficiency play major pathogenetic roles. However, there is growing evidence that other antidiabetic drugs, such as metformin, dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists, and thiazolidinediones, might have a role in optimizing glycemic control and preserving beta cell function in individuals with LADA, either alone or in combination with insulin. Although most of these drugs have been routinely used in the daily clinical setting for years, large prospective randomized trials are needed to assess whether they are capable of delaying progression to insulin dependence as well as their effects on diabetic complications. The aim of the present review is to discuss the current state and future perspectives of LADA therapy, emphasizing the need for individualized and patient-centered therapeutic approaches.

Pharmacologic adjunctive to insulin therapies in type 1 diabetes: The journey has just begun

Treatment of type 1 diabetes (T1D) is currently based exclusively on insulin replacement therapy. However, there is a need for better glycemic control, lower hypoglycemia rates, more effective weight management, and further reduction of cardiovascular risk in people with T1D. In this context, agents from the pharmaceutical quiver of type 2 diabetes are being tested in clinical trials, as adjunctive to insulin therapies for T1D patients. Despite the limited amount of relevant evidence and the inter-class variability, it can be said that these agents have a role in optimizing metabolic control, assisting weight management and reducing glycemic variability in people with T1D. Specific safety issues, including the increased risk of hypoglycemia and diabetic ketoacidosis, as well as the effects of these treatments on major cardiovascular outcomes should be further assessed by future studies, before these therapeutic choices become widely available for T1D management.

Report from the 4th Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group

The 4th Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group was held in Munich on 25–26 October 2018. As in previous years, this summit served as a reference meeting for in-depth discussions on the topic of recently completed and presented CVOTs. This year, focus was placed on the CVOTs CARMELINA, DECLARE-TIMI 58 and Harmony Outcomes. Trial implications for diabetes management and the impact of the new ADA/EASD consensus statement treatment algorithm were highlighted for diabetologists, cardiologists, endocrinologists, nephrologists and general practitioners. Discussions evolved from CVOTs to additional therapy options for heart failure (ARNI), knowledge gained for adjunct therapy of type 1 diabetes and, on the occasion of the 10 year anniversary of the FDA’s “Guidance for Industry: “should CVOTs be continued and/or modified?” The 5th Cardiovascular Outcome Trial Summit will be held in Munich on 24–25 October 2019 (http://www.cvot.org).

Adjunct Antihyperglycemic Agents in Overweight and Obese Adults With Type 1 Diabetes

OBJECTIVE

People with type 1 diabetes often have suboptimal glycemic control. The gold standard of treatment is basal-bolus insulin or subcutaneous insulin infusion via insulin pump. Although insulin therapy improves glycemic control, weight gain and hypoglycemia often limit achievement of hemoglobin A_1C (A1C) goals. The number of people with type 1 diabetes who are overweight or obese is increasing, and there are many similarities between what was historically called type 1 and type 2 diabetes. Therefore, there is rationale for using antihyperglycemic agents that target other pathophysiological abnormalities to facilitate weight loss and improve glycemic control.

DATA SOURCES

We performed a MEDLINE search from 1975 through October 2018 to identify articles that studied noninsulin agents in adults with type 1 diabetes and body mass index (BMI) ≥25 kg/m².

STUDY SELECTION AND DATA EXTRACTION

Identified articles were included if the study duration was ≥4 weeks, included ≥20 patients, and set mean baseline BMI ⩾25kg/m².

DATA SYNTHESIS

This review summarizes 32 clinical trials. Amylin mimetics, sodium-glucose-like transporter-2 inhibitors, and glucagon-like-peptide-1 receptor agonists demonstrate the greatest improvements in body weight and A1C. The most common adverse effects are hypoglycemia and ketosis. Relevance to Patient Care and Clinical Practice: Patients with type 1 diabetes may have interest in starting noninsulin agents. Clinicians need to be knowledgeable in the efficacy and adverse effect profile of these agents, specifically in people with type 1 diabetes.

CONCLUSIONS

Adding noninsulin antihyperglycemic agents may benefit select overweight or obese adults with type 1 diabetes. These agents are off-label, and if used, close monitoring is essential.