Reduced dose of rivaroxaban and dabigatran vs. vitamin K antagonists in very elderly patients with atrial fibrillation in a nationwide cohort study

Effectiveness and Safety of Edoxaban Compared With Apixaban in Elderly Patients With Nonvalvular Atrial Fibrillation: A Real-World Population-Based Cohort Study

BACKGROUND

The very elderly (≥80 years) are at high risk of nonvalvular atrial fibrillation and thromboembolism. Given its recent approval, the comparative effectiveness and safety of edoxaban in this population, relative to the commonly used apixaban, remain unknown.

METHODS

Using the United Kingdom Clinical Practice Research Datalink, we identified a cohort of patients aged ≥80 with incident nonvalvular atrial fibrillation and newly treated with edoxaban or apixaban between 2015 and 2021. Cohort entry was defined as the first prescription for one of the 2 drugs. We used propensity score fine stratification and weighting for confounding adjustment. A weighted Cox proportional hazards model was used to estimate the hazard ratios (HR) with 95% CI of ischemic stroke/transient ischemic attack/systemic embolism (primary effectiveness outcome) and of major bleeding (primary safety outcome) associated with edoxaban compared with apixaban. We also assessed the risk of all-cause mortality and a composite outcome of ischemic stroke/transient ischemic attack, systemic embolism, gastrointestinal bleeding, and intracranial hemorrhage as secondary outcomes.

RESULTS

The cohort included 7251 new-users of edoxaban and 39 991 of apixaban. Edoxaban and apixaban had similar incidence rates of thromboembolism (adjusted rates, 20.38 versus 19.22 per 1000 person-years; adjusted HR, 1.06 [95% CI, 0.89-1.26]), although the rates of major bleeding were higher with edoxaban (adjusted rates, 45.57 versus 31.21 per 1000 person-years; adjusted HR, 1.42 [95% CI, 1.26-1.61]). The risk of the composite outcome was 21% higher with edoxaban (adjusted HR, 1.21 [95% CI, 1.07-1.38]). All-cause mortality was similar between edoxaban and apixaban (adjusted HR, 1.04 [95% CI, 0.96-1.12]).

CONCLUSIONS

In very elderly patients with nonvalvular atrial fibrillation, edoxaban resulted in similar thromboembolism prevention as apixaban, although it was associated with a higher risk of major bleeding. These findings may improve the management of nonvalvular atrial fibrillation by informing physicians on the choice of anticoagulant for this vulnerable population.

Cardiovascular and renal diseases in type 2 diabetes patients: 5-year cumulative incidence of the first occurred manifestation and hospitalization cost: a cohort within the French SNDS nationwide claims database

BACKGROUND

Myocardial infarction (MI), stroke, peripheral arterial disease (PAD), heart failure (HF) and chronic kidney disease (CKD) are common cardiovascular renal diseases (CVRD) manifestations for type 2 diabetes. The objective was to estimate the incidence of the first occurring CVRD manifestation and cumulative hospitalization costs of each CVRD manifestation for type 2 diabetes without CVRD history.

METHODS

A cohort study of all type 2 diabetes free of CVRD as of January 1st 2014, was identified and followed-up for 5 years within the French SNDS nationwide claims database. The cumulative incidence of the first occurring CVRD manifestation was estimated using the cumulative incidence function, with death as a competing risk. Cumulative hospitalization costs of each CVRD manifestations were estimated from the perspective of all payers.

RESULTS

From 2,079,089 type 2 diabetes without cancer or transplantation, 76.5% were free of CVRD at baseline with a mean age of 65 years, 52% of women and 7% with microvascular complications history. The cumulative incidence of a first CVRD manifestation was 15.3% after 5 years of follow-up with a constant linear increase over time for all CVRD manifestations: The most frequent was CKD representing 40.6% of first occurred CVRD manifestation, followed by HF (23.0%), then PAD (13.5%), stroke (13.2%) and MI (9.7%). HF and CKD together reached about one patient out of ten after 5 years and represented 63.6% of first CVRD manifestations. The 5-year global cost of all CVRD hospitalizations was 3.9 billion euros (B€), i.e. 2,450€ per patient of the whole cohort, with an exponential increase over time for each specific CVRD manifestation. The costliest was CKD (2.0 B€), followed by HF (1.2 B€), then PAD (0.7 B€), stroke (0.6 B€) and MI (0.3 B€).

CONCLUSIONS/INTERPRETATION

While MI, stroke and PAD remain classic major risks of complications for CVRD-free type 2 diabetes, HF and CKD nowadays represent individually a higher risk and cost than each of these classic manifestations, and jointly represents a risk and a cost twice as high as these three classic manifestations all together. This should encourage the development of specific HF and CKD preventive strategies.

Standard- vs. low-dose rivaroxaban in patients with atrial fibrillation: a systematic review and meta-analysis

PURPOSE

Low-dose rivaroxaban is often given to patients with atrial fibrillation (AF) around the world, but the rationale for its use remains unclear. We aimed to compare the efficacy and safety of standard- or low-dose rivaroxaban in patients with AF through systematic review of literature with meta-analysis.

METHODS

We searched PubMed, Web of Science, EMBASE, Clinical Trials.gov, the Cochrane Library, and Bayer trial website from inception of each database until June 2020. Randomized controlled trials (RCTs) and cohort studies were included in the meta-analysis. A random-effects model was employed to calculate the pooled effect estimates.

RESULTS

Two RCTs and 17 cohort studies were included in the qualitative analysis. Indirect comparison of RCTs showed no significant difference between the two rivaroxaban dosages in risk of efficacy or safety outcomes (p > 0.05). Indirect comparison of cohort studies showed a lower risk of MACE among Caucasians in standard-dose group (HR 0.779; 95% CI 0.687-0.884; p < 0.001). Bleeding outcomes did not differ significantly between the two dosage regimens in Asian or Caucasian populations, except that the standard dose was associated with higher risk of major bleeding among elderly Caucasian patients (HR 1.329; 95% CI 1.141-1.547; p < 0.001). The quality of evidence was rated ranging from very low to low for all the efficacy and safety outcomes.

CONCLUSION

In Caucasians with AF, standard-dose rivaroxaban may prevent MACE significantly better than low-dose treatment. Further studies in Asians are needed to verify the advantages of the standard dose.

Effectiveness and Safety of Dabigatran Compared to Vitamin K Antagonists in Non-Asian Patients with Atrial Fibrillation: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

Real-life data about the use of dabigatran in patients with non-valvular atrial fibrillation are warranted. The objective of this systematic review and meta-analysis was to assess the effectiveness and safety of dabigatran, globally and stratified by dose (110/150 mg twice daily), vs vitamin K antagonists in non-Asian patients with non-valvular atrial fibrillation from "real-world" studies.

METHODS

A systematic review was performed according to Cochrane methodological standards. The results were reported according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses Statement) statement. The ROBINS-I tool was used to assess bias risk. MEDLINE and EMBASE, from inception up to May 2021, using appropriate controlled vocabulary and free search terms, were searched.  RESULTS: A total of 34 studies, corresponding to 37 articles involving 1,600,722 participants (1,154,283 exposed to vitamin K antagonists and 446,439 to dabigatran) were eligible for this review. Dabigatran 150 mg reduced the risk of ischemic stroke compared with vitamin K antagonists, with a 14% risk reduction (hazard ratio [HR] 0.86, 95% confidence interval [CI] 0.74-0.98). Globally, dabigatran reduced the risk of all-cause mortality compared with vitamin K antagonists (HR 0.76, 95% CI 0.69-0.84), with a greater effect observed with dabigatran 150 mg (HR 0.65, 95% CI 0.58-0.73). There was a trend towards a lower risk of myocardial infarction with dabigatran 150 mg (HR 0.86, 95% CI 0.71-1.04). Regarding the primary safety outcomes, dabigatran (either at a dose of 150 mg or 110 mg) reduced the risk of major bleeding compared with vitamin K antagonists (HR 0.77, 95% CI 0.70-0.83), as well as the risk of intracranial bleeding (HR 0.44, 95% CI 0.39-0.50) and fatal bleeding (HR 0.76, 95% CI 0.60-0.95), but with a slight increase in gastrointestinal bleeding risk (HR 1.16, 95% CI 1.08-1.26).

CONCLUSIONS

Dabigatran has a favorable impact on effectiveness and safety outcomes compared with vitamin K antagonists in real-world populations.

One-year Follow-up Results of the Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry

BACKGROUND

The high prevalence of atrial fibrillation (AF) in the very elderly population (aged >80 years) might be underestimated. The elderly are at increased risk of both fatal stroke and bleeding. The Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry provides contemporary management strategies among the elderly Chinese patients in the new era of non-vitamin K antagonists.

OBJECTIVE

To present the 1-year follow-up data from the ChiOTEAF registry, focusing on the use of antithrombotic therapy, rate vs. rhythm control strategies, and determinants of mortality and stroke.

METHODS

The ChiOTEAF registry analyzed consecutive AF patients presenting in 44 centers from 20 Chinese provinces from October 2014 to December 2018. Endpoints of interest were mortality, thromboembolism, major bleedings, cardiovascular comorbidities, and hospital re-admissions.

RESULTS

Of the 7077 patients enrolled at baseline, 657 patients (9.3%) were lost to the follow-up and 435 deaths (6.8%) occurred. The overall use of anticoagulants remains low, approximately 38% of the entire cohort at follow-up, with similar proportions of vitamin K antagonists (VKA) and non-vitamin K antagonists (NOACs). Antiplatelet therapy was used in 38% of the entire cohort at follow-up, and more commonly among high-risk patients (41%). Among those on a NOAC at baseline, 22.4% switched to antiplatelet therapy alone after one year.Independent predictors of stroke/transient ischemic attack/peripheral embolism and/or mortality were age, heart failure, chronic kidney disease, prior ischemic stroke, dementia, and chronic obstructive pulmonary disease.

CONCLUSIONS

The ChiOTEAF registry provides contemporary data on AF management, including stroke prevention. The poor adherence of NOACs and common use of antiplatelet in these high-risk elderly population calls for multiple comorbidities management.

Review Article: Gastrointestinal Bleeding Risk with Direct Oral Anticoagulants

PURPOSE

Although direct oral anticoagulants (DOACs) are associated with an overall favourable safety profile, the risk of gastrointestinal bleeding with DOACs compared with vitamin K antagonists (VKAs) remains controversial. Accordingly, we aimed to provide a focused overview of the risk of gastrointestinal bleeding associated with dabigatran, rivaroxaban, apixaban and edoxaban and its management.

METHODS

We reviewed published studies reporting on DOACs with gastrointestinal bleeding as an outcome, including randomised controlled trials (RCTs), retrospective database studies and large-scale prospective cohort studies.

RESULTS

Cumulative evidence confirms no notable difference in major gastrointestinal bleeding risk between DOACs and VKAs. Moreover, gastrointestinal bleeding in DOAC-treated patients seems less severe and requires less intensive management. The main cause of upper gastrointestinal bleeding in DOAC-treated patients appears to be gastroduodenal ulcers, whereas lower gastrointestinal bleedings are mainly due to diverticula followed by angiodysplasia and haemorrhoids. The lack of head-to-head RCTs with DOACs precludes drawing conclusions on the DOAC with the lowest gastrointestinal bleeding risk. Prescribing physicians should be aware of risk factors for DOAC-related gastrointestinal bleeding (e.g. age > 65, heavy alcohol use, uncontrolled hypertension, hepatic or renal dysfunction, active cancer, anaemia) and adopt preventive measures accordingly. Management of DOAC-associated major gastrointestinal bleeding involves temporary discontinuation of the DOAC, investigation of the bleeding source and treatment of bleeding with fluid resuscitation combined with transfusion and endoscopic haemostasis.

CONCLUSION

DOACs as a class do not increase the risk of major gastrointestinal bleeding compared to VKAs, which supports their continued use for different anticoagulant indications.

Stroke prevention strategies in high-risk patients with atrial fibrillation

Effective stroke prevention with oral anticoagulation (OAC) is the cornerstone of the management of patients with atrial fibrillation. The use of OAC reduces the risk of stroke and death. For most patients with atrial fibrillation without moderate or severe mitral valve stenosis or prosthetic mechanical heart valves, treatment options include vitamin K antagonists, such as warfarin, and non-vitamin K antagonist oral anticoagulants (NOACs). Although most guidelines generally recommend NOACs as the first-line OAC, caution is required in some groups of patients with atrial fibrillation at high risk of stroke and bleeding who have been under-represented or not studied in the randomized clinical trials on NOACs for stroke prevention. In addition to OAC, non-pharmacological, percutaneous therapies, including left atrial appendage occlusion, for stroke prevention have emerged, sometimes used in combination with catheter ablation for the treatment of the atrial fibrillation. High-risk groups of patients with atrial fibrillation include patients with end-stage renal failure (including those receiving dialysis), extremely old patients (such as those aged >80 years with multiple risk factors for bleeding), patients with dementia or those living in a long-term care home, patients with previous intracranial bleeding or recent acute bleeding (such as gastrointestinal bleeding), patients with acute ischaemic stroke and patients with an intracardiac thrombus. This Review provides an overview of stroke prevention strategies, including left atrial appendage occlusion, in patients with atrial fibrillation at high risk of stroke and bleeding.

Non-Vitamin K Antagonist Oral Anticoagulants and the Gastrointestinal Bleeding Risk in Real-World Studies

In the present study, we aimed to provide evidence from high-quality real world studies for a comprehensive and rigorous analysis on the gastrointestinal bleeding (GIB) risk for non-vitamin K antagonist oral anticoagulants (NOACs). We performed a systematic search of MEDLINE, EMBASE and PUBMED, and of 286 records screened, we included data from 11 high-quality real-world studies, coordinated by independent research groups over the last 3 years, that reported major GIB events in patients given NOACs or vitamin K antagonists for patients with nonvalvular atrial fibrillation. The lowest risk of gastrointestinal bleeding was with apixaban compared with warfarin (hazard ratio (HR) for GIB for apixaban ranging between 0.45 (95% confidence interval (CI) 0.34 to 0.59) and 1.13 (95% CI 0.79 to 1.63)). Apixaban was associated with a lower risk of GI bleeding than dabigatran ((HR ranging between 0.39 (95% CI 0.27 to 0.58) and 0.95 (95% CI 0.65 to 1.18)) or rivaroxaban ((HR ranging between 0.33 (95% CI 0.22 to 0.49) and 0.82 (95% CI 0.62 to 1.08)). The results of our study confirm a low or a similar risk for major GIB between patients receiving apixaban or dabigatran compared with warfarin, and apixaban appears to be associated with the lowest risk of GIB.