Initiation of glucose-lowering treatment decreases international normalized ratio levels among users of vitamin K antagonists: a self-controlled register study

Efficacy and Safety of Direct Oral Anticoagulants in Patients with Diabetes and Nonvalvular Atrial Fibrillation: Meta-Analysis of Observational Studies

Background

This meta-analysis was performed to compare the efficacy and safety of direct oral anticoagulants (DOACs) with vitamin K antagonists (VKAs) for stroke prevention in real-world patients with diabetes and nonvalvular atrial fibrillation (NVAF) through observational studies.

Methods

PubMed, Embase, and Web of Science databases were searched up to August 2020 for eligible studies. Outputs were presented as risk ratios (RRs) and corresponding 95% confidence intervals (CIs) by using a random-effect model.

Results

Seven observational studies involving 249,794 diabetic NVAF patients were selected. Compared with VKAs, the use of DOACs was associated with significantly reduced risks of stroke (RR = 0.56, 95% CI 0.45-0.70; p < 0.00001), ischemic stroke (RR = 0.61, 95% CI 0.48-0.78; p < 0.0001), stroke or systemic embolism (SSE) (RR = 0.81, 95% CI 0.68-0.95; p = 0.01), myocardial infarction (RR = 0.69, 95% CI 0.55-0.88; p = 0.002), major bleeding (RR = 0.75, 95% CI 0.63-0.90; p = 0.002), intracranial hemorrhage (RR = 0.50, 95% CI 0.44-0.56; p < 0.00001), and major gastrointestinal bleeding (RR = 0.77, 95% CI 0.62-0.95; p = 0.02), and a borderline significant decrease in major adverse cardiac events (RR = 0.87, 95% CI 0.75-1.00; p = 0.05) in NVAF patients with diabetes.

Conclusion

For patients with NVAF and diabetes in real-world clinical settings, DOACs showed superior efficacy and safety profile over VKAs and significantly reduced risks of stroke, ischemic stroke, SSE, myocardial infarction, major bleeding, intracranial hemorrhage, and major gastrointestinal bleeding.

The Safety and Efficacy of Rivaroxaban Compared with Warfarin in Patients with Atrial Fibrillation and Diabetes: A Systematic Review and Meta-analysis

AIMS

This meta-analysis was conducted to compare the efficacy and safety of rivaroxaban with warfarin in patients with atrial fibrillation (AF) and diabetes mellitus.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science databases were systematically searched from the establishment of databases up to 15 October 2019. Studies on efficacy and safety outcomes of rivaroxaban and warfarin were included. Efficacy and safety outcomes, including stroke, ischemic stroke, stroke or systemic embolism, myocardial infarction, major adverse cardiac events, major bleeding, intracranial hemorrhage, and major gastrointestinal bleeding were collected for meta-analysis.

RESULTS

Compared with warfarin, rivaroxaban could significantly reduce stroke (risk ratio [RR] 0.77; 95% confidence interval [CI] 0.63-0.95; P = 0.01), ischemic stroke (RR 0.74; 95% CI 0.63-0.87; P = 0.0004), stroke or systemic embolism (RR 0.73; 95% CI 0.60-0.89; P = 0.002), myocardial infarction (RR 0.68; 95% CI 0.56-0.82; P < 0.0001), and major adverse cardiac events (RR 0.71; 95% CI 0.53-0.94; P = 0.02) in patients with AF and diabetes. Moreover, rivaroxaban was associated with a lower risk of major bleeding (RR 0.79; 95% CI 0.65-0.96; P = 0.02), intracranial hemorrhage (RR 0.52; 95% CI 0.39-0.69; P < 0.00001), and major gastrointestinal bleeding (RR 0.74; 95% CI 0.56-0.98; P = 0.04). Similar results were obtained in stratified meta-analysis of cohort studies.

CONCLUSION

Our study suggests a favorable risk-benefit profile of rivaroxaban, with superior efficacy and safety over warfarin in patients with AF and diabetes.

Sulfonylureas and Metformin Were Not Associated With an Increased Rate of Serious Bleeding in Warfarin Users: A Self-Controlled Case Series Study

Drug interactions between warfarin and sulfonylureas are suggested by pharmacokinetic information and prior studies. However, clinical evidence on the association of such interactions and the risk of bleeding is lacking. Using healthcare claims data from 5 US Medicaid programs from 1999-2011 and a self-controlled case series design with warfarin as an object drug, we calculated confounder-adjusted rate ratios (RRs) for concomitant use of sulfonylureas and metformin for 3 outcomes separately: (i) serious bleeding as a composite outcome of gastrointestinal bleeding (GIB) and nontraumatic intracranial hemorrhage (ICH); (ii) GIB; and (iii) ICH. In 6,463 warfarin users experiencing serious bleeding, an increased rate of serious bleeding was not associated with concomitant use of glimepiride (RR: 0.93; 95% confidence interval (CI) 0.75-1.15), glipizide (RR: 0.97; 95% CI 0.84-1.13), glyburide (RR: 0.89; 95% CI 0.76-1.06), or metformin (RR: 0.85; 95% CI 0.76-0.96), nor was the occurrence of the component outcomes of GIB or ICH. These results suggest that use of sulfonylureas or metformin was not associated with an increased rate of serious bleeding in warfarin users.

Effective INR Level May Be Delayed in Secondary Prevention of Stroke Due to Atrial Fibrillation with Warfarin in the Patients with Diabetes Mellitus

Introduction

Warfarin is a drug used for anticoagulation in diseases, especially atrial fibrillation (AF). The effectiveness of warfarin is monitored by the International Normalized Ratio (INR) and should be kept between 2.0 and 3.0 in the AF clinic. This drug the significant variability in dose response and the narrow therapeutic index among individuals. However, the effective INR level may not be achieved due to some reasons, or the time to achieve the effective INR level may lengthen. Our aim in this study is to investigate whether there is a difference in terms of dose and duration in achieving the effective INR level by the warfarin treatment due to the coexistence of AF and stroke between patients with and without diabetes mellitus (DM).

Methods

A total of 70 patients whose warfarin treatment was initiated due to non-valvular AF and who were diagnosed with acute ischemic stroke were included in the study, 30 of these patients were DM patients and 40 were non-DM patients. The total dose and time values at achieving the effective INR level after the initiation of warfarin treatment according to the clinical protocol during follow-ups in hospital were statistically compared between the two groups.

Results

In the study, it was found that the total warfarin dose was significantly higher in the DM group compared to the non DM group (p<0.05). It was detected that the time to achieve the effective INR level was also significantly longer in the DM group than in the non-DM group (p<0.05).

Conclusion

In the presence of DM diagnosis, the higher dose warfarin and longer follow-up are required to achieve effective INR levels in stroke patients whose warfarin treatment was initiated due to non-valvular AF.

Early Discontinuation of Metformin in Individuals Treated with Inhibitors of Transporters of Metformin

The aim of this study was to examine the risk of early discontinuation of metformin as a proxy for intolerance, associated with use of drugs known to inhibit transporters involved in metformin distribution. We analysed all incident users of metformin in Denmark between 2000 and 2012 (n = 132,221) and in a cohort of US patients (n = 296,903). Risk of early discontinuation of metformin was assessed using adjusted logistic regression for 28 drugs putatively inhibiting metformin transporters and four negative controls. Increased odds ratio of early discontinuation of metformin was only associated with codeine, an inhibitor of organic cation transporter 1 in both cohorts [adjusted odds ratio (OR) in Danish cohort (95% CI): 1.13 (1.02-1.26), adjusted OR in American cohort (95% CI): 1.32 (1.19-1.47)]. The remaining drugs were not associated with increased odds ratio of early discontinuation and, surprisingly, four drugs were associated with a decreased risk. These findings indicate that codeine use may be associated with risk of early discontinuation of metformin and could be used as a basis for further investigation.