Progression to treatment failure among Chinese patients with type 2 diabetes initiated on metformin versus sulphonylurea monotherapy--The Hong Kong Diabetes Registry

Real world evidence of clinical predictors of glycaemic response to glucose-lowering drugs among Chinese with type 2 diabetes

AIMS

To examine whether simple clinical features can predict the 1-year glycaemic response to glucose-lowering drugs (GLDs) among Chinese with type 2 diabetes.

MATERIALS AND METHODS

We used data from a diabetes risk assessment and complication screening programme and electronic medical records. We used linear regression models to examine the association between clinical features and 1-year glycaemic response to GLDs.

RESULTS

Use of metformin (n = 15,433), sulphonylureas (SU) (n = 15,190), dipeptidyl peptidase-4 inhibitor (DPP-4i) (n = 7947), thiazolidinedione (TZD) (n = 4107), and sodium-glucose cotransporter 2 inhibitors (SGLT-2i) (n = 1883) were associated with a mean reduction of HbA1c ranging from 0.7% to 1.3% at one year. Men had a greater response to SU but a poorer response to metformin and TZD. Older age predicted a better response to all GLDs but not SGLT-2i, whereas increasing diabetes duration was associated with a poorer response to all GLDs except for DPP-4i. Obese patients responded greater to TZD and SGLT-2i but poorer to SU than those with normal weight. Patients with a higher level of triglycerides to high-density lipoprotein cholesterol ratio had a greater glycaemic response to TZD but a smaller response to SU and DPP-4i.

CONCLUSIONS

Glycaemic response to GLDs differed considerably by clinical features among Chinese patients with type 2 diabetes.

CYP2C19 Loss-of-function Polymorphisms are Associated with Reduced Risk of Sulfonylurea Treatment Failure in Chinese Patients with Type 2 Diabetes

Sulfonylureas (SUs) are predominantly metabolized by cytochrome p450 2C9 (CYP2C9) and cytochrome p450 2C19 (CYP2C19) enzymes. CYP2C9 polymorphisms are associated with greater treatment response and hypoglycemic risk in SU users. However, there are no large scale pharmacogenetic studies investigating the effect of loss‐of‐function alleles CYP2C19*2 and CYP2C19*3, which occur frequently in East Asians. Retrospective pharmacogenetic analysis was performed in 11,495 genotyped patients who were enrolled in the Hong Kong Diabetes Register between 1995 and 2017, with follow‐up to December 31, 2019. The associations of CYP2C19 polymorphisms with SU treatment failure, early HbA1c response, and severe hypoglycemia were analyzed by Cox regression or logistic regression assuming an additive genetic model. There were 2341 incident SU users that were identified (mean age 59 years, median diabetes duration 9 years), of which 324 were CYP2C19 poor metabolizers (CYP2C19 *2/*2 or *2/*3 or *3/*3). CYP2C19 poor metabolizers had lower risk of SU treatment failure (hazard ratio 0.83, 95% confidence interval (CI) 0.72–0.97, P = 0.018) and were more likely to reach the HbA1c treatment target < 7% (odds ratio 1.52, 95% CI 1.02–2.27, P = 0.039) than wild‐type carriers (CYP2C19 *1/*1) following adjustment for multiple covariates. There were no significant differences in severe hypoglycemia rates among different CYP2C19 genotype groups. CYP2C19 polymorphisms should be considered during personalization of SU therapy.

Early combination therapy delayed treatment escalation in newly diagnosed young-onset type 2 diabetes: A subanalysis of the VERIFY study

We analysed glycaemic durability (sustained glycaemic control) with early combination therapy (metformin plus vildagliptin) versus metformin monotherapy, among patients with type 2 diabetes diagnosed before (young-onset [YOD]) and after (late-onset [LOD]) the age of 40 years, enrolled in the VERIFY trial. The primary endpoint was time to initial treatment failure (TF), defined as HbA1c of 7.0% or higher at two consecutive scheduled visits after randomization. The time to secondary TF was assessed when both groups were receiving and failing on the combination. A total of 186 (9.3%) patients had YOD and 1815 (90.7%) had LOD with a mean age difference of 20.4 years. Compared with metformin monotherapy, early combination reduced the risk of time to initial TF for both YOD (48%, P < .0006) and LOD (46%, P < .0001). With early combination, risk for time to secondary TF was reduced by 48% (P < .0035) in YOD and 24% (P < .0009) in LOD. Both treatment approaches were well tolerated with no unexpected safety concerns. In treatment-naïve patients with YOD (HbA1c 6.5%-7.5%), an early combination strategy improved attainment of the glycaemic target with durability and delayed treatment escalation compared with initial metformin monotherapy.

Precision medicine in diabetes prevention, classification and management

Diabetes has become a major burden of healthcare expenditure. Diabetes management following a uniform treatment algorithm is often associated with progressive treatment failure and development of diabetic complications. Recent advances in our understanding of the genomic architecture of diabetes and its complications have provided the framework for development of precision medicine to personalize diabetes prevention and management. In the present review, we summarized recent advances in the understanding of the genetic basis of diabetes and its complications. From a clinician's perspective, we attempted to provide a balanced perspective on the utility of genomic medicine in the field of diabetes. Using genetic information to guide management of monogenic forms of diabetes represents the best-known examples of genomic medicine for diabetes. Although major strides have been made in genetic research for diabetes, its complications and pharmacogenetics, ongoing efforts are required to translate these findings into practice by incorporating genetic information into a risk prediction model for prioritization of treatment strategies, as well as using multi-omic analyses to discover novel drug targets with companion diagnostics. Further research is also required to ensure the appropriate use of this information to empower individuals and healthcare professionals to make personalized decisions for achieving the optimal outcome.

Effectiveness of sulphonylureas in the therapy of diabetes mellitus type 2 patients: an observational cohort study

BACKGROUND

We compared all-cause mortality, major macrovascular events (MACE) and diabetes-related hospitalizations in T2DM-incident patients newly treated with metformin (MET) versus sulphonylureas (SU) monotherapy and in T2DM-prevalent patients newly treated with MET+SU versus MET+DPP4-inhibitor combination therapy.

METHODS

We analysed anonymized data obtained from a German health fund. Patients were included when they had started MET versus SU therapy or MET+SU versus MET+DPP4 therapy between 01/07/2010 and 31/12/2011. Observation started with the first MET/SU prescription or the first prescription of the second agent of a MET+SU/MET+DPP4 combination therapy. Follow-up time lasted until the end of data availability (a minimum of 12 months), death or therapy discontinuation.

RESULTS

In total, 434,291 T2DM-prevalent and 35,661 T2DM-incident patients were identified. Of the identified T2DM-incident patients, 904/7,874 started SU/MET monotherapy, respectively, with a mean age of 70.1/61.4 years (54.6/50.3 % female; Charlson Comorbidity Index (CCI) 1.4/2.2; 933/7,350 observed SU/MET patient years). 4,157/1,793 SU+MET/DPP4+MET therapy starters had a mean age of 68.1/62.2 years (53.4/50.8 % female; CCI 2.8/2.6; 4,556/1,752 observed SU+MET/ DPP4+MET patient years). In a propensity score matched (PSM) comparison, the HRs (95 % CIs) associated with SU monotherapy compared to MET monotherapy exposure were 1.4 (0.9-2.3) for mortality, 1.4 (0.9-2.2) for MACE, 4.1 (1.5-10.9) for T2DM hospitalizations and 1.6 (1.2-2.3) for composite event risk. In a multivariable Cox regression model, SU monotherapy was associated with higher mortality (aHR 2.0; 1.5-2.6), higher MACE (aHR 1.3; 1.0-1.7) and higher T2DM hospitalizations (aHR 2.8; 1.8-4.4), which corresponded with a higher composite event risk (aHR 1.8; 1.5-2.1). No significant differences in event rates were observed in the PSM comparison between DPP4+MET/SU+MET combination therapy starters and in the multivariable Cox regression analysis.

CONCLUSIONS

Our results show that SU monotherapy may be associated with increased mortality, MACE and T2DM hospitalizations, compared to MET monotherapy. When considering SU therapy, the associated cardiovascular risk should also be taken into account.