Effect of short-term treatment with sitagliptin or glibenclamide on daily glucose fluctuation in drug-naïve Japanese patients with type 2 diabetes mellitus

Comparison of glucose fluctuation between metformin combined with acarbose or sitagliptin in Chinese patients with type 2 diabetes: A multicenter, randomized, active-controlled, open-label, parallel design clinical trial

BACKGROUND

Alpha-glucosidase inhibitors or dipeptidyl peptidase-4 inhibitors are both hypoglycemia agents that specifically impact on postprandial hyperglycemia. We compared the effects of acarbose and sitagliptin add on to metformin on time in range (TIR) and glycemic variability (GV) in Chinese patients with type 2 diabetes mellitus through continuous glucose monitoring (CGM).

METHODS

In this multicenter, randomized, open-label, active-controlled study, we recruited patients with type 2 diabetes mellitus aged 18-65 years with body mass index (BMI) within 19-40 kg/m2 and hemoglobin A1c (HbA1c) between 6.5% and 9.0%. Eligible patients were randomized to receive either metformin combined with acarbose 100 mg three times daily or metformin combined with sitagliptin 100 mg once daily for 28 days. After the first 14-day treatment period, patients wore CGM and entered another 14-day treatment period. The primary outcome was the level of TIR after treatment between groups. We also performed time series decomposition, dimensionality reduction, and clustering using the CGM data.

RESULTS

A total of 701 participants received either acarbose or sitagliptin treatment in combination with metformin. There was no statistically significant difference in TIR between the two groups. Time below range (TBR) and coefficient of variation (CV) levels in acarbose users were significantly lower than those in sitagliptin users. TBR below target level <3.9 mmol/L (TBR3.9): Acarbose: 2.86 ± 6.98% vs. Sitagliptin: 3.89 ± 9.43%, P = 0.042; TBR3.0: Acarbose: 0.96 ± 4.41% vs. Sitagliptin: 1.64 ± 6.73%, P = 0.033; CV: Acarbose: 22.44 ± 5.08% vs. Sitagliptin: 23.96 ± 5.19%, P <0.001. No significant difference was found in the complexity of glucose time series index (CGI) between acarbose users and sitagliptin users. By using time series analysis and clustering, we distinguished three groups of patients with representative metabolism characteristics, especially in GV.

CONCLUSIONS

Acarbose had slight advantages over sitagliptin in improving GV and reducing the risk of hypoglycemia. Time series analysis of CGM data may predict GV and the risk of hypoglycemia.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR2000039424.

Effect of Intensive Lifestyle Intervention on Cardiovascular Risk Factors: Analysis From the Perspective of Long-Term Variability

BACKGROUND

An association between variability of cardiovascular risk factors and cardiovascular events has been reported. We examined whether intensive lifestyle intervention (ILI) for weight loss decreased variability of cardiovascular risk factors with a view to additional cardiometabolic benefits.

METHODS AND RESULTS

This study was a post hoc secondary analysis of the Look AHEAD (Action for Health in Diabetes) study. Cardiovascular risk factors were measured at 1-year intervals for 4 years in 4249 adults with overweight or obesity and type 2 diabetes who were randomly assigned to ILI or diabetes support and education. Long-term variability was defined as the SD of cardiovascular risk factors during 4-year follow-up. At multiple linear regression analysis, compared with the diabetes support and education group, the ILI group was associated with reduced variability of fasting blood glucose (β=-1.49 [95% CI, -2.39 to -0.59]), total cholesterol (β=-1.12 [95% CI, -1.75 to -0.48]), and low-density lipoprotein cholesterol (β=-1.04 [95% CI, -1.59 to -0.49]), as well as increased variability of systolic blood pressure (β=0.27 [95% CI, 0.00-0.54]). No significant effect of ILI was found on the variability of diastolic blood pressure (β=-0.08 [95% CI, -0.22 to 0.05]).

CONCLUSIONS

Among adults with overweight or obesity and type 2 diabetes, ILI may reduce long-term variability of fasting blood glucose, total cholesterol, and low-density lipoprotein cholesterol. Our results support that ILI should be recommended to individuals with diabetes as part of management of long-term glycemic and blood lipid control.

Association Between the Variability of Glycated Hemoglobin and Retinopathy in Patients with Type 2 Diabetes Mellitus: A Meta-Analysis

Visit-to-visit variability of glycated hemoglobin (HbA1c) is a marker of long-term glycemic fluctuation, which has been related to increased risk of macrovascular complications in patients with type 2 diabetes mellitus (T2DM). The association between HbA1c variability and retinopathy in patients with T2DM, however, has been inconsistent in previous studies. In order to fully evaluate the above association, we conducted a meta-analysis. Observational studies related to the aim of the meta-analysis were identified by search of PubMed, Web of Science, and Embase databases. Studies with HbA1c variability evaluated as the standard deviation (SD) and/or the coefficients of variation (CV) of HbA1c were included. The results were analyzed using a random-effects model that incorporated potential heterogeneity between studies. Twelve observational studies involving 44 662 T2DM patients contributed to the meta-analysis. Overall, 5150 (11.5%) patients developed retinopathy. Pooled results showed that compared to patients with lower HbA1c variability, T2DM patients with higher HbA1c-SD (relative risk [RR]: 1.48, 95% confidence interval [CI]: 1.24 to 1.78, p<0.001, I2=34%) and higher HbA1c-CV (RR: 1.29, 95% CI: 1.05 to 1.59, p=0.02, I2=0%) were both associated with higher risk of DR. For studies with HbA1c-SD, the association was not significantly affected by study characteristics such as country, study design, mean age, disease duration, adjustment of mean HbA1c, or quality scores (p for subgroup difference all>0.05). In conclusion, higher HbA1c variability may be associated with an increased risk of retinopathy in patients with T2DM.

Reporting and methodological quality of systematic reviews of DPP-4 inhibitors for patients with type 2 diabetes mellitus: an evidence-based mapping

AIMS

To evaluate the reporting and methodological quality of relevant systematic reviews (SRs) and meta-analyses (MAs) on Dipeptidyl peptidase-4 inhibitors (DPP-4I) for Type 2 diabetes mellitus (T2DM).

METHODS

Relevant SRs and MAs on T2DM and DPP-4I published between 2017 and November 2021 were retrieved from PubMed, Embase, Cochrane Library, Web of Science, VIP, CNKI, CBM, and WanFang databases. Two independent reviewers performed the search, selection, and data extraction. The reporting and methodological quality of the reviewers was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR 2) tools. The relationship between reporting and methodological quality score was assessed with the Spearman correlation test.

RESULTS

Twenty-one studies involving 151,715 participants were included in the study. This overview showed that DPP-4I was safer and more efficacious than other anti-hyperglycemic drugs (OADs) in treating T2DM. The methodological quality of one SR was low, while the rest were very low. Thus, refinements are needed in the quality of protocol and registration information, a complete search strategy, the summary of the evidence, the listing of excluded studies, assessing the potential impact of risk of bias in RCTs, and discussing the RoB on MA results, and the funding of RCTs need improvement for generating SR. In addition, the reporting and methodological quality scores were moderately correlated (r_S = 0.66, P = 0.001).

CONCLUSIONS

DPP-4I is safer and more efficacious than OADs in treating T2DM. However, the reporting and methodological quality of the related SRs was unsatisfactory. Therefore, PRISMA and AMSTAR 2 analyses should be followed to enhance the overall quality of future SRs.

Hypoglycemic agents and glycemic variability in individuals with type 2 diabetes: A systematic review and network meta-analysis

While hemoglobin A1c (HbA1c) is commonly used to monitor therapy response in type 2 diabetes (T2D), GV is emerging as an essential additional metric for optimizing glycemic control. Our goal was to learn more about the impact of hypoglycemic agents on HbA1c levels and GV in patients with T2D. A systematic review and network meta-analysis (NMA) of randomized controlled trials were performed to assess the effects of glucagon-like peptide 1 receptor agonists (GLP-1 RAs), sodium-glucose cotransporter (SGLT)-2 inhibitors, dipeptidyl peptidase (DPP)-4 inhibitors, sulfonylurea and thiazolidinediones on Mean Amplitude of Glycemic Excursions (MAGE) and HbA1c. Searches were performed using PubMed and EMBASE. A random-effect model was used in the NMA, and the surface under the cumulative ranking was used to rank comparisons. All studies were checked for quality according to their design and also for heterogeneity before inclusion in this NMA. The highest reduction in MAGE was achieved by GLP-1 RAs (SUCRA 0.83), followed by DPP-4 inhibitors (SUCRA: 0.72), and thiazolidinediones (SUCRA: 0.69). In terms of HbA1c reduction, GLP-1 RAs were the most effective (SUCRA 0.81), followed by DPP-4 inhibitors (SUCRA 0.72) and sulfonylurea (SUCRA 0.65). Our findings indicated that GLP-1 RAs have relatively high efficacy in terms of HbA1c and MAGE reduction when compared with other hypoglycemic agents and can thus have clinical application. Future studies with a larger sample size and appropriate subgroup analyses are warranted to completely understand the glycemic effects of these agents in various patients with T2D. The protocol for this systematic review was registered with the International Prospective Register of Systematic Reviews (CRD42021256363).

Influence of dipeptidyl peptidase-4 inhibitors on glycemic variability in patients with type 2 diabetes: A meta-analysis of randomized controlled trials

OBJECTIVE

The influence of dipeptidyl peptidase-4 (DPP4) inhibitors on glycemic variability compared to other oral antidiabetic drugs (OADs), measured based on the mean amplitude of glycemic excursions (MAGE), has not been comprehensively analyzed. The aim of the study was to perform a meta-analysis to compare the effects of DPP4 inhibitors on MAGE with other OADs in type 2 diabetes mellitus (T2DM) patients without concurrent insulin treatments.

METHODS

The Medline (PubMed), Embase (Ovid), and CENTER (Cochrane Library) databases were searched for relevant randomized controlled trials (RCTs). Study characteristics and outcome data were independently extracted by two authors. A random-effect model was used to combine the results.

RESULTS

Fourteen studies with 855 patients were included. Compared to other OADs, DPP4 inhibitors significantly reduced MAGE (mean difference [MD]: -0.69 mmol/L, 95% confidence interval [CI]: -0.95 to -0.43, P<0.001) with mild heterogeneity (I^{2 =} 28%). Predefined subgroup analyses suggested that DPP4 inhibitors were more effective in reducing MAGE compared to insulin secretagogues (MD: -0.92 mmol/L, P<0.001) and non-secretagogues (MD: -0.43 mmol/L, P=0.02), as well as compared to sulfonylureas (MD: -0.91 mmol/L, P<0.001) and sodium glucose cotransporter 2 inhibitors (MD: -0.67 mmol/L, P=0.03).

CONCLUSIONS

DPP4 inhibitors may significantly reduce glycemic variability compared to other oral anti-diabetic drugs, as evidenced by MAGE in T2DM patients with no concurrent insulin treatment.

SYSTEMATIC REVIEW REGISTRATION

INPLASY, registration number: INPLASY2021120113.

A Comprehensive Review and Perspective on Natural Sources as Dipeptidyl Peptidase-4 Inhibitors for Management of Diabetes

Type 2 diabetes mellitus (T2DM) is an increasing global public health problem, and its prevalence is expected to rise in coming decades. Dipeptidyl peptidase-4 (DPP-4) is a therapeutic target for the management of T2DM, and its inhibitors prevent the degradation of glucose-dependent insulinotropic peptide and glucagon-like peptide 1, and thus, maintain their endogenous levels and lower blood glucose levels. Various medicinal plant extracts and isolated bioactive compounds exhibit DPP-4 inhibitory activity. In this review, we discussed different natural sources that have been shown to have anti-diabetic efficacy with a particular emphasis on DPP-4 inhibition. Furthermore, the effect of DPP-4 inhibition on pancreatic beta cell function, skeletal muscle function, and the glucose-lowering mechanisms were also discussed. We believe that scientists looking for novel compounds with therapeutic promise against T2DM will be able to develop antidiabetic drugs using these natural sources.

Log-linear relationship between endogenous insulin secretion and glycemic variability in patients with type 2 diabetes on continuous glucose monitoring

The contribution of endogenous insulin secretion to glycemic variability (GV) may differ between patients with impaired insulin secretion and those with preserved secretion. Our objective was to determine the linearity of the relationship between fasting C-peptide (CPR) as a marker of endogenous insulin secretion and GV in type 2 diabetes (T2DM), regardless of the type of antidiabetic treatment. We conducted a prospective observational study using continuous glucose monitoring obtained from 284 Japanese outpatients with T2DM with various HbA1c values and antidiabetic treatment. We constructed a prediction curve of base-line CPR versus coefficient of variation (CV) and identified the clinical factors associated with CV using multiple regression analysis. Fasting CPR showed a significant negative log-linear relationship with CV (P < 0.0001), and the latter being strikingly high in the low-CPR group. The multiple regression analysis showed that low CPR was an independent predictor of high CV (P < 0.0001). The significant correlations were sustained in both patients with/without insulin treatment. The contribution of endogenous insulin secretion to GV depends on the extent of insulin secretion impairment. Fasting CPR may represent a useful indicator of GV instability in T2DM.

Effects of DPP-4 Inhibitors on Blood Glucose Variability in Japanese Patients with Type 2 Diabetes on Maintenance Hemodialysis: A Prospective Observational Exploratory Study

INTRODUCTION

The precise blood glucose (BG) profile of hemodialysis patients is unclear, as is the effectiveness of dipeptidyl peptidase-4 (DPP-4) inhibitors in hemodialysis patients with type 2 diabetes. Here, we used continuous glucose monitoring (CGM) to evaluate BG variability in these patients and to assess the efficacy of DPP-4 inhibitors, particularly during hemodialysis sessions and at nighttime (UMIN000012638).

METHODS

We examined BG profiles using CGM in 31 maintenance hemodialysis patients with type 2 diabetes. Differences between patients with and without DPP-4 inhibitors (n = 15 and 16, respectively) were analyzed using a linear mixed-effects model to assess changes in glucose levels in 5-min intervals.

RESULTS

The model revealed that DPP-4 inhibitor use was significantly associated with suppression of a rapid drop in glucose levels, both with and without adjustment for BG levels at the start of hemodialysis. Moreover, the model revealed that the two groups differed significantly in the pattern of changes in BG levels from 0:00 to 6:55 am. DPP-4 inhibitors suppressed the tendency for subsequent nocturnal hypoglycemia.

CONCLUSIONS

This prospective observational exploratory study showed that DPP-4 inhibitors could suppress BG variability during hemodialysis sessions as well as subsequent nocturnal changes in patients with type 2 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, UMIN000012638.

Effect of DPP-IV Inhibitors on Glycemic Variability in Patients with T2DM: A Systematic Review and Meta-Analysis

Glycemic variability (GV) has been an emerging target for preventing complications related to type 2 diabetes. For reducing GV, DPP-IV inhibitors have shown effectiveness compared to other oral anti-hyperglycemic drugs (OADs), but systematic evaluation has yet to be existed. A systematic review and meta-analysis of randomized controlled trials (RCTs) were performed to evaluate the effect of DPP-IV inhibitors compared with other OADs, on GV as measured by mean amplitude of glycemic excursions (MAGE). Searches were conducted using Pubmed, EMBASE, and the Cochrane Library, from which eligible studies were retrieved; seven RCTs were included in the analysis. DPP-IV inhibitors were found to significantly reduce MAGE compared to other OADs (mean difference = -14.61; 95% CI = -19.00 to -10.21; p < 0.0001) without significant heterogeneity among sulfonylureas (mean difference = -14.93; 95% CI = -21.60 to -8.26; p < 0.0001). Initial combination therapy with DPP-IV inhibitors more effectively reduced MAGE than stepwise add-on therapies (p = 0.006), although no differences in MAGE were found based on HbA1c values. These findings indicate that DPP-IV inhibitors are promising alternatives for reducing GV in type 2 diabetes patients. However, further studies utilizing larger numbers of patients and longer-term follow-ups are needed.