Gastric emptying in newly diagnosed, treatment-naïve Han Chinese with type 2 diabetes and the impact of 4-week insulin pump therapy

AIM

To evaluate gastric emptying (GE) and the glycaemic response to a 75-g oral glucose load in newly diagnosed, treatment-naïve Han Chinese with type 2 diabetes (T2D) before insulin pump therapy, after 4 weeks of insulin pump therapy, and 12-15 months after insulin pump therapy.

MATERIALS AND METHODS

Twenty participants with T2D (baseline glycated haemoglobin [± SD] 10.7% [± 1.2%] 93 [± 10] mmol/mol) ingested a 75-g glucose drink containing 150 mg 13C-acetate, to determine the gastric half-emptying time, and underwent assessment of plasma glucose and serum insulin, C-peptide and glucagon-like peptide-1 (GLP-1) over 180 min before and after 4 weeks of insulin pump therapy (discontinued for 48 h before re-assessment). Data were compared to those in 19 healthy participants matched for sex and age. After 12-15 months, GE was re-measured in 14 of the T2D participants.

RESULTS

At baseline, participants with T2D exhibited substantially augmented fasting and post-glucose glycaemia, diminished insulin secretion, and more rapid GE (p < 0.05 each), but comparable GLP-1, compared to healthy participants. Following insulin pump therapy, insulin secretion increased, GLP-1 secretion was attenuated, fasting and post-glucose glycaemia were lower, and GE was slowed (p < 0.05 each). The slowing of GE in T2D participants was sustained over 12-15 months of follow-up.

CONCLUSIONS

In newly diagnosed Han Chinese with T2D, GE is often accelerated despite poor glycaemic control and is slowed by short-term insulin pump therapy. The effect on GE is maintained for at least 12 months.

Saxagliptin/dapagliflozin is non-inferior to insulin glargine in terms of β-cell function in subjects with latent autoimmune diabetes in adults: A 12-month, randomized, comparator-controlled pilot study

AIM

To compare the efficacy and safety of saxagliptin/dapagliflozin and insulin glargine in people with latent autoimmune diabetes in adults (LADA).

METHODS

In this phase 2b multicentre, open-label, comparator-controlled, parallel-group, non-inferiority study, we randomly assigned 33 people with LADA who had a fasting C-peptide concentration ≥0.2 nmol/L (0.6 ng/mL) to receive 1-year daily treatment with either the combination of saxagliptin (5 mg) plus dapagliflozin (10 mg) or insulin glargine (starting dose: 10 IU), both on top of metformin. The primary outcome was the 2-h mixed meal-stimulated C-peptide area under the curve (AUC), measured 12 months after randomization. Secondary outcomes were glycated haemoglobin (HbA1c) levels, change in body mass index (BMI), and hypoglycaemic events.

RESULTS

In the modified intention-to-treat analysis, the primary outcome was similar in participants assigned to saxagliptin/dapagliflozin or to insulin glargine (median C-peptide AUC: 152.0 ng*min/mL [95% confidence interval {CI} 68.2; 357.4] vs. 122.2 ng*min/mL [95% CI 84.3; 255.8]; p for noninferiority = 0.0087). Participants randomized to saxagliptin/dapagliflozin lost more weight than those randomized to insulin glargine (median BMI change at the end of the study: -0.4 kg/m2 [95% CI -1.6; -0.3] vs. +0.4 kg/m2 [95% CI -0.3; +1.1]; p = 0.0076). No differences in HbA1c or in the number of participants experiencing hypoglycaemic events were found.

CONCLUSIONS

Saxagliptin/dapagliflozin was non-inferior to glargine in terms of β-cell function in this 12-month, small, phase 2b study, enrolling people with LADA with still viable endogenous insulin production. Weight loss was greater with saxagliptin/dapagliflozin, with no differences in glycaemic control or hypoglycaemic risk.

Plasma serpinB1 is related to insulin sensitivity but not pancreatic β-Cell function in non-diabetic adults

Pancreatic β‐cell dysfunction because of reduced β‐cell mass and function is a primary determinant in the progression of diabetes. Increase in β‐cell mass and compensatory hyperinsulinaemia is frequently associated with insulin‐resistant states. Although the humoral factors mediating this compensatory response are unknown, serpinB1, a protease inhibitor, has recently been proposed to be one such factor. In this study, we examine the relationships between plasma serpinB1, insulin sensitivity, and pancreatic β‐cell function in non‐diabetic individuals. 117 subjects (women, n = 50, men, n = 67; age= 37.6 ± 10.8; BMI=31.1 ± 7.7 kg/m²) underwent an insulin‐modified frequently sampled intravenous glucose tolerance test (FSIVGTT) at the NIH Clinical Research Center. Acute insulin response (AIR) and insulin sensitivity index (SI) were obtained from the FSIVGTT with MINMOD analysis. The Quantitative Insulin Sensitivity Check Index (QUICKI) was calculated from fasting insulin and glucose values. Plasma serpinB1 levels were measured using an ELISA assay. Simple linear correlation analyses were performed to evaluate the relationship between serpinB1 and measures of insulin sensitivity and β‐cell function. Circulating serpinB1 levels were unrelated to age, sex, race, BMI, or percent body fat. SI but not AIR significantly correlated with circulating serpinB1 levels (r = 0.23, P < 0.05). QUICKI tended to positively correlate with serpinB1 (r = 0.16, P = 0.09). Circulating serpinB1 is directly associated with insulin sensitivity but not β‐cell function in non‐diabetic adults. Whether this modest association plays a role in insulin sensitivity in humans remains to be clarified.

Secretory units of islets in transplantation index is a useful predictor of insulin requirement in Japanese type 2 diabetic patients

AIMS/INTRODUCTION

The objective of the present study was to clarify the validity of β-cell function-related parameters for predicting the insulin requirement of Japanese type 2 diabetic patients.

MATERIALS AND METHODS

In 188 patients with type 2 diabetes who had been admitted to the University of Toyama Hospital (Toyama, Japan) without receiving insulin therapy, we carried out a cross-sectional study examining the relationship between the homeostasis model assessment of β-cell function (HOMA-β) and C-peptide-based indices, and also carried out a retrospective study to examine the utility for predicting insulin requirement of several β -cell function-related indices using a receiver operating characteristic (ROC) curve analysis.

RESULTS

The secretory units of islets in transplantation index (SUIT) had the strongest correlation with HOMA-β, followed by the fasting serum C-peptide immunoreactivity index (CPI); the fasting serum C-peptide immunoreactivity itself (F-CPR) had the least correlation. The CPI, HOMA-β and SUIT were significantly lower in the insulin-requiring group than in the non-insulin-requiring group, even after adjustments for confounding factors (P < 0.01). The areas under the ROC curve for insulin requirement were 0.622, 0.774, 0.808, and 0.759 for F-CPR, CPI, SUIT, and HOMA-β, respectively. The cut-off values of SUIT, CPI, and HOMA-β for an over 80% specificity for the prediction of insulin therapy were 23.5, 1.00, and 14.9, respectively.

CONCLUSIONS

The present study shows that SUIT is the best predictor of insulin requirement among these β-cell function-related markers.