Clinical predictors and time course of the improvement in β-cell function with short-term intensive insulin therapy in patients with Type 2 diabetes

Intervention with Therapeutic Agents, Understanding the Path to Remission in Type 2 Diabetes: Part 1

Type 2 diabetes is characterized by progressive decline in pancreatic β-cell function. Studies in adult subjects with newly diagnosed type 2 diabetes have reported that intensive insulin therapy followed by various antihyperglycemic medications can delay β-cell decline. However, this improvement is lost after cessation of therapy. In contrast, youth with type 2 diabetes experience a more rapid loss in β-cell function compared with adults and have loss of β-cell function despite being on insulin and other antihyperglycemic medications. In part one of this two-part review, we discuss studies aiming to achieve diabetes remission with insulin and oral antidiabetic medications.

Efficacy and safety of a basal insulin + 2-3 oral antihyperglycaemic drugs regimen versus a twice-daily premixed insulin + metformin regimen after short-term intensive insulin therapy in individuals with type 2 diabetes: The multicentre, open-label, randomized controlled BEYOND-V trial

AIM

To compare the efficacy and safety of basal insulin glargine 100 units/ml (Gla) + 2-3 oral antihyperglycaemic drugs (OADs) with twice-daily premixed insulin aspart 70/30 (Asp30) + metformin (MET) after short-term intensive insulin therapy in adults with type 2 diabetes in China.

MATERIALS AND METHODS

This open-label trial enrolled insulin-naïve adults with type 2 diabetes and an HbA1c of 7.5%-11.0% (58-97 mmol/mol) despite treatment with 2-3 OADs. All participants stopped previous OADs except MET, then received short-term intensive insulin therapy during the run-in period, when those with a fasting plasma glucose of less than 7.0 mmol/L and 2-hour postprandial glucose of less than 10.0 mmol/L were randomized to Gla + MET + a dipeptidyl peptidase-4 inhibitor or twice-daily Asp30 + MET. If HbA1c was more than 7.0% (>53 mmol/mol) at week 12, participants in the Gla group were added repaglinide or acarbose, at the physician's discretion, and participants in the Asp30 group continued to titrate insulin dose. The change in HbA1c from baseline to week 24 was assessed in the per protocol (PP) population (primary endpoint).

RESULTS

There were 384 enrollees (192 each to Gla and Asp30); 367 were included in the PP analysis. The threshold for non-inferiority of Gla + OADs versus Asp30 + MET was met, with a least squares mean change from baseline in HbA1c of -1.72% and -1.70% (-42.2 and -42.1 mmol/mol), respectively (estimated difference -0.01%; 95% CI -0.20%, 0.17% [-0.1 mmol/mol; 95% CI -2.2, 1.9]). Achievement of HbA1c less than 7.0% (<53 mmol/mol) was comparable between the groups (60% vs. 57%). The proportion of participants with any (24% vs. 38%; P = .003), symptomatic (19% vs. 31%; P = .007) or confirmed hypoglycaemia (18% vs. 33%; P < .001) was lower in the Gla + OADs group.

CONCLUSIONS

Compared with Asp30 + MET, Gla + 2-3 OADs showed similar efficacy but a lower hypoglycaemia risk in Chinese individuals with type 2 diabetes who had undergone short-term intensive insulin therapy.

Efficacy and Safety of Basal Insulin-Based Treatment Versus Twice-Daily Premixed Insulin After Short-Term Intensive Insulin Therapy in Patients with Type 2 Diabetes Mellitus in China: Study Protocol for a Randomized Controlled Trial (BEYOND V)

INTRODUCTION

Many Chinese patients who are uncontrolled by oral antidiabetic drugs (OADs) receive short-term intensive insulin therapy (IIT) in hospital to rapidly relieve glucose-associated toxicity and to preserve/improve β-cell function. However, evidence for optimizing insulin algorithms for maintenance treatment after IIT is lacking. This study will compare the efficacy and safety of basal insulin-based treatment versus twice-daily premixed insulin in type 2 diabetes mellitus (T2DM) patients after short-term in-hospital IIT.

METHODS

This 26-week randomized, multicenter, positive-controlled, open-label, parallel-group study will enroll approximately 400 male and female patients aged 18-70 years with poorly-controlled T2DM (HbA1c > 7.5%) despite treatment with metformin plus at least one other OAD for 8 or more weeks. During a run-in period of 7-10 days, patients will be treated in-hospital with IIT comprising insulin glargine (Lantus^®) once daily and insulin glulisine (Apidra^®) three times daily; both regimens will be titrated daily to achieve the glycemic goal. Eligible patients will then be randomized in a 1:1 ratio to insulin glargine plus OADs or twice-daily premixed insulin (NovoLog^® Mix 70/30) for 24 weeks, with metformin maintained throughout the study in both treatment groups. The primary endpoint is HbA1c change from baseline to week 24. Secondary endpoints include assessment of fasting plasma glucose, total daily insulin dose, hypoglycemia incidence, body weight change, adverse events, and patient satisfaction.

DISCUSSION

Given the current lack of clinical data, this study will provide evidence supporting safe and effective glycemic control using basal insulin glargine-based therapy plus OADs compared with twice-daily premixed insulin in Chinese patients with T2DM after short-term IIT. This will assist physicians by providing a wider choice of treatments.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03359837 (registered on 2 December 2017).

Effect of short-term intensive insulin therapy on α-cell function in patients with newly diagnosed type 2 diabetes

The effect of intensive insulin therapy on hyperglucagonemia in newly diagnosed type 2 diabetes (T2DM), and its associations with β-cell function, has not been elucidated. This study assessed the effect of 12 weeks of intensive insulin therapy on hyperglucagonemia in newly diagnosed T2DM and its associations with β-cell function, with reference to the effects of 12 weeks of oral hypoglycemic agents (OHAs).One hundred eight patients with newly diagnosed T2DM were enrolled from January 2015 to December 2015. The patients were randomly divided to receive, for 12 weeks, either intensive insulin therapy or OHAs. Meal tolerance tests were conducted at baseline before treatment (0 week), at 12 weeks (end of treatment), and 12 months after the initiation of treatment. The levels of glucagon, proinsulin, C-peptide (CP), and blood glucose were measured at timepoints 0, 30, and 120 minutes during the meal tolerance test.Intensive insulin treatment was associated with a decrease in glucagon levels (at 0, 30, and 120 minutes) and proinsulin/CP, and an increase in the insulin-secretion index ΔCP30/ΔG30 and ΔCP120/ΔG120, at 12 weeks and 12 months during the follow-up, compared with the corresponding effects of OHAs. Intensive insulin therapy could reduce but failed to normalize glucagon levels at 12 weeks. There were no correlations between the change of percentages in total area under the curve of glucagon and other glycemic parameters (proinsulin/CP; ΔCP30/ΔG30; or ΔCP120/ΔG120). Patients who received intensive insulin therapy were more likely to achieve their target glycemic goal and remission, compared with those who received OHAs.Short-term intensive insulin therapy facilitates the improvement of both β-cell and α-cell function in newly diagnosed T2DM mellitus. Decline of β-cell secretion and concomitant α-cell dysfunction may both be involved in the pathogenesis of T2DM.

Hypoglycemia during Short-Term Intensive Insulin Therapy and Its Association with Long-Term Glycemic Remission in Patients with Newly Diagnosed Type 2 Diabetes

BACKGROUND

Short-term intensive insulin therapy induces long-term glycemic remission in half of patients with newly diagnosed type 2 diabetes. The concomitant hypoglycemia needs further analysis.

METHODS

We collected data from three randomized trials conducted with the same inclusion and exclusion criteria at our institution from 2002 to 2015. Continuous subcutaneous insulin infusion (CSII) was provided to achieve the glycemic goals within a week and then maintained for 14 days. Hypoglycemia episodes during short-term treatment and the one-year drug-free glycemic remission were observed.

RESULTS

A total of 244 patients were included. The per day episode of mild hypoglycemia (3.0-3.9 mmol/L) was higher in the remission group than in the nonremission group (0.26 ± 0.20 vs. 0.18 ± 0.21, P = 0.005). However, a moderate hypoglycemia episode (<3.0 mmol/L) per day was insignificantly lower in the remission group (0.02 ± 0.04 vs. 0.03 ± 0.04, P = 0.005). However, a moderate hypoglycemia episode (<3.0 mmol/L) per day was insignificantly lower in the remission group (0.02 ± 0.04 vs. 0.03 ± 0.04, P = 0.005). However, a moderate hypoglycemia episode (<3.0 mmol/L) per day was insignificantly lower in the remission group (0.02 ± 0.04 vs. 0.03 ± 0.04, P = 0.005). However, a moderate hypoglycemia episode (<3.0 mmol/L) per day was insignificantly lower in the remission group (0.02 ± 0.04 vs. 0.03 ± 0.04.

CONCLUSIONS

Mild hypoglycemic episodes during the continuing insulin dose reduction period indicate a long-term drug-free euglycemic remission in patients with newly diagnosed type 2 diabetes. However, the insulin dosage should be reduced even more quickly in the future treatment to decrease the potential harms.

Cardiovascular risk of sitagliptin in treating patients with type 2 diabetes mellitus

Patients with type 2 diabetes mellitus (T2DM) have a very high risk of cardiovascular related events, and reducing complications is an important evaluation criterion of efficacy and safety of hypoglycemic drugs. Previous studies have shown that the dipeptidyl peptidase-4 (DPP-4) inhibitors (DPP4i), such as sitagliptin, might reduce the incidence of major cardiovascular events (MACEs). However, the safety and efficacy of sitagliptin remains controversial, especially the safety for cardiovascular related events. Here, a systematic review was conducted to assess the cardiovascular safety of sitagliptin in T2DM patients. The literature research dating up to October 2018 was performed in the electronic database. The clinical trials about sitagliptin for T2DM patients were included. Two reviewers independently screened literature according to the inclusion and exclusion criteria. The primary outcome was the MACE, and the secondary outcome was all-cause mortality. Finally, 32 clinical trials composed of 16082 T2DM patients were included in this meta-analysis. The results showed that: there was no significant difference between sitagliptin group and the control group on MACE (odds ratio (OR) = 0.85, 95% confidence intervals (CIs) = 0.63–1.15), myocardial infarction (MI) (OR = 0.66, 95% CI = 0.38–1.16), stroke (OR = 0.83, 95% CI = 0.44–1.54) and mortality (OR = 0.52, 95% CI = 0.26–1.07). These results demonstrated that sitagliptin did not increase the risk of cardiovascular events in patients with T2DM.

INTERMITTENT INTENSIVE INSULIN THERAPY FOR TYPE 2 DIABETES: EFFECTS ON HYPOGLYCEMIA, WEIGHT GAIN, AND QUALITY OF LIFE OVER 2 YEARS

Objective: In early type 2 diabetes (T2DM), the administration of short-term intensive insulin therapy (IIT) can induce glycemic remission for a year thereafter, but this effect ultimately wanes. In this context, intermittently repeating short-term IIT could provide a strategy for maintaining the otherwise transient benefits of this intervention. However, the viability of this strategy would be contingent upon not inducing undesirable effects of insulin therapy such as excessive hypoglycemia and fat deposition. We thus sought to evaluate the effect of administering short-term IIT every 3 months on hypoglycemia, weight gain, and quality of life in early T2DM. Methods: In this 2-year pilot trial, 24 adults with T2DM of 2.0 ± 1.7 years duration and hemoglobin A1c of 6.4 (46 mmol/mol) ± 0.1% were randomized to 3 weeks of IIT (glargine, lispro) followed by either (1), repeat IIT for up to 2 weeks every 3 months or (2), daily metformin. IIT was titrated to target near-normoglycemia (premeal glucose 4 to 6 mmol/L; 2-hour postmeal <8 mmol/L). Participants were assessed every 3 months, with quality of life (QOL) evaluated annually. Results: The rate of hypoglycemia (<3.5 mmol/L) was low in the metformin and intermittent IIT arms (0.37 versus 0.95 events per patient-year; P = .28). There were no differences between the groups in changes over time in overall, central, or hepatic fat deposition (as reflected by weight [P = .10], waist-to-hip ratio [P = .58], and alanine aminotransferase [P = .64], respectively). Moreover, there were no differences between the groups in QOL at 1- and 2-years. Conclusion: Intermittent short-term IIT may be safely administered in early T2DM without excessive adverse impact on hypoglycemic risk, anthropometry, or QOL. Abbreviations: ALT = alanine aminotransferase; HbA1c = hemoglobin A1c; IIT = intensive insulin therapy; ISSI-2 = insulin secretion-sensitivity index-2; OGTT = oral glucose tolerance test; QOL = quality of life; SF-36 = medical outcomes study 36-item short-form health survey; T2DM = type 2 diabetes.

Should the last be first? Questions and dilemmas regarding early short-term insulin treatment in Type 2 Diabetes Mellitus

INTRODUCTION

Early short-term insulin treatment (STIT), defined as insulin administration shortly after diabetes diagnosis for only a brief period of time, is an alternative concept, aiming to entirely revise the perspective of type 2 diabetes (T2DM) management.

AREAS COVERED

The present review intends to summarize what is already known regarding early STIT in T2DM and highlight questions and dilemmas from the clinician's point of view, with a discourse on future research agenda.

EXPERT OPINION

STIT has the potential to modify the natural history of T2DM, resulting in improved drug-free remission rates by favorably affecting the underlying pathophysiology of the disease. Existing data in the field manifest significant weaknesses, mainly being the small number of trials and patients included, the lack of control groups in most studies and the wide heterogeneity between study designs and explored outcomes, which limit definitive conclusions. Therefore, before such a therapeutic strategy is incorporated into daily practice, important issues require further clarification by future trials. These issues include the optimal time point for the intervention, the ideal insulin type, the identification of patients being most likely to benefit, the STIT effects on cardiovascular and other clinical outcomes and the cost-effectiveness evaluation of this therapeutic strategy.

ABBREVIATIONS

T2DM: Type 2 Diabetes Mellitus; HbA_1C: Hemoglobin A_1c; OHA: Oral Hypoglycemic Agents; STIT: Short-term Insulin Treatment; CSII: Continuous Subcutaneous Insulin Infusion; MDI: Multiple Daily Injections; PPG: Postprandial Plasma Glucose; FPG: Fasting Plasma Glucose; HOMA-b: Homeostasis Model Assessment of beta-cell function; TDD: Total Daily Insulin Dose; DI: Disposition Index; HOMA-IR: Homeostasis Model Assessment of Insulin Resistance; ROS: Reactive Oxygen Species; TNF: Tumor Necrosis Factor; GLP-1: Glucagon-like peptide-1; GIP: Glucose-dependent Insulinotropic Polypeptide; BMI: Body Mass Index; CV: Cardiovascular; DR: Diabetic Retinopathy; SU: Sulfonylurea; IGI: Insulinogenic Index.

Two-year trial of intermittent insulin therapy vs metformin for the preservation of β-cell function after initial short-term intensive insulin induction in early type 2 diabetes

AIMS

To test the hypothesis that "induction" intensive insulin therapy (IIT) needs to be followed by "maintenance therapy" to preserve β-cell function, and to evaluate the impact on β-cell function over 2 years of two approaches to maintenance therapy: intermittent short-term IIT every 3 months vs daily metformin.

MATERIALS AND METHODS

In this trial, 24 adults with a mean type 2 diabetes mellitus (T2DM) duration of 2.0 ± 1.7 years and glycated haemoglobin (HbA1c) levels 6.4 ± 0.1% (46 ± 1.1mmol/mol) were randomized to 3 weeks of induction IIT (glargine, lispro) followed by either repeat IIT for up to 2 weeks every 3 months or daily metformin. Participants underwent serial assessment of β-cell function using the Insulin Secretion-Sensitivity Index-2 (ISSI-2) on an oral glucose tolerance test every 3 months.

RESULTS

The primary outcome of baseline-adjusted ISSI-2 at 2 years was higher in the metformin arm compared with intermittent IIT (245.0 ± 31.7 vs 142.2 ± 18.4; P = .008). Baseline-adjusted HbA1c at 2 years (secondary outcome) was lower in the metformin arm (6.0 ± 0.2% vs 7.3 ± 0.2%; P = .0006) (42 ± 2.2 vs 56 ± 2.2mmol/mol). At study completion, 66.7% of participants randomized to metformin had an HbA1c concentration ≤ 6.0% (≤42mmol/mol), compared with 8.3% of those on intermittent IIT (P = .009). There were no differences in insulin sensitivity.

CONCLUSION

After induction IIT, metformin was superior to intermittent IIT for maintaining β-cell function and glycaemic control over 2 years. The strategy of induction and maintenance therapy to preserve β-cell function warrants exploration in early T2DM.

Comparative Study of Liraglutide and Insulin Glargine on Glycemic Control and Pancreatic β-Cell Function in db/db Mice

Background

The aim of this study was to compare the effects of liraglutide, a long-acting glucagon-like peptide-1 (GLP-1) receptor agonist, and insulin glargine, a long-acting insulin analog, on glycemic control and pancreatic β-cell function in db/db mice.

Material/Methods

Eight-week-old male db/db mice (n=40) were divided into five groups: the vehicle-treated group (VG) (n=8); the insulin glargine-treated group (GG) (dose, 450 mg/kg) (n=8), the low-dose liraglutide-treated group (LLG) (dose, 75 μg/kg) (n=8), the mid-dose liraglutide-treated group (MLG) (150 μg/kg) (n=8), and the high-dose liraglutide-treated group (HLG) (300 μg/kg) (n=8), treated with subcutaneous injection once daily, from 8–14 weeks-of-age. Body weight, pancreatic weight, levels of blood glucose, triacylglycerol, C-peptide, and the intraperitoneal glucose tolerance test (IPGTT) were used. Expression levels of the INS1 gene were measured using reverse transcription polymerase chain reaction (RT-PCR), and pancreatic and duodenal homeobox 1 (Pdx1), paired box 4 (Pax4), and paired box 6 (Pax6) mRNA expression were measured.

Results

Both insulin glargine and liraglutide improved glycemic control of db/db mice when compared with vehicle. The following were significantly increased in the HLG compared with the GG: the receiver operating characteristic (ROC) area under the curve (AUC) for the IPGTT; C-peptide levels; the pancreas to body weight coefficient; expression levels of the INS1 gene and pancreatic transcription factors Pdx1, Pax4 and Pax6. Liraglutide treatment was without hypoglycemic effects.

Conclusions

Liraglutide acted in a dose-dependent manner on glycemic control of db/db mice, and was more effective than insulin glargine, when administered at a high dose.

Fasting Plasma Glucose Indicates Reversibility of the Acute Insulin Response after Short-Term Intensive Insulin Therapy in Patients with Various Duration of Type 2 Diabetes

Recovery of acute insulin response (AIR) is shown to be associated with long-term outcomes of patients with early type 2 diabetes treated with short-term intensive insulin therapy (SIIT). However, the complexity of measuring an AIR limits its utility in a real-world clinical setting. The aim of the study was to assess fasting indicators that may estimate recovery of the AIR after SIIT. We enrolled 62 patients with type 2 diabetes mellitus (T2DM) of varying disease duration who had poor glycemic control. Participants were treated with SIIT using insulin pumps to achieve near normoglycemia for 7 days. The AIR before and after the therapy were measured by intravenous glucose tolerance tests. After the therapy, AIR increased from -16.7 (-117.4, 52.4) pmol/L·min to 178.7 (31.8, 390.7) pmol/L·min (P < 0.001) while hyperglycemia was alleviated; this improvement was observed in all disease duration categories. AIR was almost absent when fasting plasma glucose (FPG) > 10 mmol/L, while both AIR (R = -0.53, P < 0.001) and its improvement from baseline (△AIR, R = -0.52, P < 0.001) were negatively associated with FPG after SIIT when FPG < 10 mmol/L. In multivariate analyses, FPG after SIIT and baseline fasting C peptide were independent indicators of both AIR after the therapy and ∆AIR; HDL-C after the therapy also predicted AIR after the therapy. We concluded that recovery of the AIR could be obtained in T2DM patients of varying disease duration by SIIT and it could be conveniently estimated using posttreatment fasting plasma glucose and other fasting indicators.

Predictors of sustained drug-free diabetes remission over 48 weeks following short-term intensive insulin therapy in early type 2 diabetes

OBJECTIVE

In early type 2 diabetes (T2DM), short-term intensive insulin therapy (IIT) for 2-4 weeks can decrease insulin resistance, reduce glucagonemia, improve β-cell function, and even induce a remission of diabetes that can last up to 1 year in some patients. However, little is known about the predictors of such a sustained remission.

METHODS

We evaluated data from the placebo arm of a double-blind randomized controlled trial in which patients with early T2DM (≤7 years duration) underwent 4 weeks of IIT (basal detemir, bolus aspart), followed by placebo therapy for 48 weeks (n=25). Participants underwent an oral glucose tolerance test every 12 weeks, enabling serial assessment of insulin sensitivity, α-cell response, and β-cell function. Diabetes remission was defined as A1c<6.5% on no medication for T2DM.

RESULTS

At 48 weeks post-IIT, 56% of the participants remained in remission. Comparison of remitters to non-remitters revealed no differences in waist, body mass index, insulin sensitivity (Matsuda index), or glucagon profile, either at baseline or over 48 weeks. Compared to non-remitters, the remission group had lower baseline A1c (p=0.006) and better baseline β-cell function (Insulin Secretion-Sensitivity Index-2) (p=0.01) that was then sustained across 48 weeks post-IIT (p=0.006). On logistic regression analyses, however, shorter duration of diabetes supplanted baseline A1c (p=0.24) and β-cell function (p=0.19) as an independent predictor of remission (p=0.04). In particular, diabetes duration <2 years predicted persistence of remission (p=0.006).

CONCLUSIONS

The key determinant of the likelihood of inducing sustained drug-free diabetes remission with short-term IIT is early intervention, particularly within the first 2 years after diagnosis.

TRIAL REGISTRATION NUMBER

ClinicalTrials.Gov NCT01270789; Post-results.