Investigation on Dabigatran Etexilate and Worsening of Renal Function in Patients with Atrial fibrillation: The IDEA Study

The Connubium among diabetes, chronic kidney disease and atrial fibrillation

The burden of cardiovascular comorbid conditions was significantly higher in patients with Atrial Fibrillation (AF); most of them are affected by hypertension, Chronic Kidney Disease (CKD) and/or Diabetes Mellitus (DM). DM represents a well-known risk factor for the development and maintenance of AF; the coexistence of DM and AF is also associated with an increased risk of mortality and stroke. Moreover, DM is currently the main cause of renal impairment and the leading cause of dialysis in the world. The hyperglycemia is responsible for inducing redox imbalance and both systemic and intrarenal inflammation, playing a critical role in the pathogenesis of diabetic kidney disease. Long-term thromboembolic preventive therapy in AF patients with DM and CKD may be more challenging because both DM and CKD have been independently associated with an increased thromboembolic and bleeding risk, which results from the prothrombotic and pro-inflammatory status. Vitamin K Antagonists (VKAs) are characterized by numerous critical issues such as a narrow therapeutic window, increased tissue calcification and an unfavourable risk/benefit ratio with low stroke prevention effect and augmented risk of major bleeding. On the other hand, Direct Oral Anticoagulants (DOACs) are currently contraindicated in dialysis patients even if mounting evidence suggests that they may have a nephroprotective role in AF patients with DM and CKD. Consequently, the choice of anticoagulant therapy in this setting of patient seems to be very challenging. The aim of this review is to investigate the role of DOACs in diabetic patients and its nephroprotective role by reviewing the current literature.

Impact of Renal Function on Effectiveness and Safety Associated With Low Dose Dabigatran in Non-valve Atrial Fibrillation Patients After Catheter Ablation

Aim: The purpose of this study is to compare the effectiveness and safety of 110 mg dabigatran in non-valve atrial fibrillation (NVAF) patients with different eGFRs.

Methods: We conducted a single-center retrospective cohort study to investigate the effectiveness and safety of 110 mg dabigatran for NVAF patients between January 2017 and December 2018 based on the eGFR category.

Results: A total of 560 NVAF patients who treated with 110 mg dabigatran were included for analysis. In 12 months, the Kaplan-Meier survival curves indicated that the lower eGFR subgroups were more likely to experience thrombosis, bleeding, and cumulative events earlier (P = 0.021 for thrombosis; P = 0.026 for bleeding; P = 0.001 for cumulative events). Gastrointestinal bleeding occurred more frequently in the moderate group than in other groups (6.94% in the moderate group vs. 1.54% in the mild group vs. 1.22% in the normal group, P = 0.028). By multivariate analysis, chronic kidney disease (P = 0.043; OR = 4.273, 95% CI 1.043–17.543) and diabetes mellitus (P = 0.023; OR = 2.194, 95% CI 1.114–4.323) were independent predictors of the composite endpoints. A positive linear relationship was observed between eGFR levels and occurrence rate of thrombosis and bleeding under anticoagulation patients with 110 mg dabigatran (R² = 0.432 and R² = 0.784, respectively).

Conclusions: Impaired renal function was associated with decreased safety and increased thrombosis risks in NVAF patients taking low dose dabigatran.

Dynamics of Kidney Function in Patients with Chronic Kidney Disease and Atrial Fibrillation Who Receive Dabigatran

Atrial fibrillation (AF) is the most frequent type of supraventricular arrhythmias. The anticoagulant therapy should be prescribed to prevent thromboembolic events. According to randomized clinical trials, anticoagulants do not always prove their high efficiency in the real clinical practice. It is a complicated issue for any doctor to prescribe the anticoagulant therapy for patients with AF and CKD. 30 % of patients with atrial fibrillation are known to have chronic kidney disease, while 10-15% of patients with chronic kidney disease are diagnosed with atrial fibrillation. Currently, there are scarce studies into the use of direct oral anticoagulants in patients with atrial fibrillation and chronic kidney disease (in case of Glomerular Filtration Rate (GFR) below 45 ml/min/1.73 m2).

Aim. To determine the dynamics of GFR in patients with AF and CKD (in case of GFR below 45 ml/min/1.73 m2).

Material and Methods. The sub-analysis was carried out to examine a single-centre prospective study into the optimization of the anticoagulant therapy in the outpatient practice. Initially, 133 dabigatran taking patients were enrolled in the study, and 79 patients were included in the final analysis. Endpoints were changes in Glomerular Filtration Rate (CKD-EPI) formulae as of the inclusion date, in 6, 12, 24 and 60 months after the inclusion. Changes in the renal function shall mean a decrease or increase in GFR by ≥5 ml/min.

Results. The average follow-up period for patients was 1785 ± 218 days. A GFR>45 ml/min/1.73 m2 occurred in 116 (87.2%) patients, and a GFR <45 ml/min/1.73 m2 was found in 17 (12.8%) patients. The average HAS-BLED score was 1.8, and CHA2DS2VASc score - 3.8. During the observation period, there were 3 cases of major bleeding and 133 cases of minor bleeding. Both major (р=0.025) and minor (р=0.012) bleeding were statistically significant more frequent in patients with GFR below 45 ml/min. During 5 years of follow-up, 66 (49.6%) patients had an average decrease in GFR of 3.32 ml/min/1.73 m2 per year. Patients with the initially declined GFR (below 45 ml/min) did not demonstrate a significant dynamic of the renal function during the dabigatran therapy. The mortality rate in this group during the observation period was 61.5%.

Conclusion. In 49.6% of patients during 5 years of follow-up, GFR decreased by an average of 3.32 ml/min/1.73 m2 per year, which does not exceed the indicators typical for patients with cardiovascular events and CKD.