Comparative effectiveness of novel oral anticoagulants in UK patients with non-valvular atrial fibrillation and chronic kidney disease: a matched cohort study

Heart failure and major haemorrhage in people with atrial fibrillation

BACKGROUND

Heart failure (HF) is not included in atrial fibrillation (AF) bleeding risk prediction scores, reflecting uncertainty regarding its importance as a risk factor for major haemorrhage. We aimed to report the relative risk of first major haemorrhage in people with HF and AF compared with people with AF without HF ('AF only').

METHODS

English primary care cohort study of 2 178 162 people aged ≥45 years in the Clinical Practice Research Datalink from January 2000 to December 2018, linked to secondary care and mortality databases. We used traditional survival analysis and competing risks methods, accounting for all-cause mortality and anticoagulation.

RESULTS

Over 7.56 years median follow-up, 60 270 people were diagnosed with HF and AF of whom 4996 (8.3%) had a major haemorrhage and 36 170 died (60.0%), compared with 8256 (6.4%) and 34 375 (27.2%), respectively, among 126 251 people with AF only. Less than half those with AF were prescribed an anticoagulant (45.6% from 2014 onwards), although 75.7% were prescribed an antiplatelet or anticoagulant. In a fully adjusted Cox model, the HR for major haemorrhage was higher among people with HF and AF (2.52, 95% CI 2.44 to 2.61) than AF only (1.87, 95% CI 1.82 to 1.92), even in a subgroup analysis of people prescribed anticoagulation. However, in a Fine and Gray competing risk model, the HR of major haemorrhage was similar for people with AF only (1.82, 95% CI 1.77 to 1.87) or HF and AF (1.71, 95% CI 1.66 to 1.78).

CONCLUSIONS

People with HF and AF are at increased risk of major haemorrhage compared with those with AF only and current prediction scores may underestimate the risk of haemorrhage in HF and AF. However, people with HF and AF are more likely to die than have a major haemorrhage and therefore an individual's expected prognosis should be carefully considered when predicting future bleeding risk.

Real-World Data on the Incidence of Stroke, Myocardial Infarction, and Mortality Among Nonvalvular Atrial Fibrillation Patients in Türkiye: New Oral Anticoagulants-TURKey Study

BACKGROUND

Atrial fibrillation (AF) is strongly associated with an increased risk of ischemic events. Anticoagulation focuses on reducing the risk of embolism. Guideline recommended CHA2DS2-VASc scoring system is most widely used; however, different scoring systems do exist. Thus, we sought to assess the impact of anticoagulant treatment and different scoring systems on the development of stroke, myocardial infarction, and all-cause mortality in patients with nonvalvular AF.

METHODS

The present study was designed as a prospective cohort study. The enrollment of the patients was conducted between August 1, 2015, and January 1, 2016. The follow-up period was defined as the time from enrollment to the end of April 1, 2017, which also provided at least 12 months of prospective follow-up for each patient.

RESULTS

A total of 1807 patients with AF were enrolled. During the follow-up, 2.7% (48) of patients had stroke, 0.8% (14) had myocardial infarction, and 7.5% (136) died. The anticoagulation and risk factors in AF (ATRIA) score had a better accuracy for the prediction of stroke compared to other scoring systems (0.729, 95% CI, 0.708-0.750, P <.05). Patients under low-dose rivaroxaban treatment had significantly worse survival (logrank P <.001). Age, CHA2DS2-VASc score, R2CHADS2 score, ATRIA score, chronic heart failure, prior stroke, and being under low-dose rivaroxaban treatment were independent predictors of clinical endpoint (P <.001).

CONCLUSION

Low-dose rivaroxaban treatment was independently and strongly associated with the combined clinical endpoint. Furthermore, the ATRIA score proved to be a stronger predictor of stroke in the Turkish population.

Effectiveness and safety of apixaban and rivaroxaban vs warfarin in patients with atrial fibrillation and chronic kidney disease

BACKGROUND

Randomized controlled trials (RCTs) of direct oral anticoagulants (DOACs) included a low proportion of atrial fibrillation (AF) patients with chronic kidney disease (CKD), and suggested that DOACs are safe and effective in patients with mild-to-moderate CKD. In a metanalysis of RCTs and observational studies, DOACs were associated with better efficacy (vs warfarin) in early CKD and had similar efficacy and safety profiles in patients with stages IV-V CKD. But few studies have provided data on the safety and effectiveness of each DOAC vs warfarin in patients with stage III CKD. The effectiveness and safety of DOACs in those patients are still subject to debate.

AIM

To assess and compare the effectiveness and safety of apixaban and rivaroxaban vs warfarin in this patient population.

METHODS

A cohort of patients with an inpatient or outpatient code for AF and stage III CKD who were newly prescribed apixaban and rivaroxaban was created using the administrative databases from the Quebec province of Canada between 2013 and 2017. The primary effectiveness outcome was a composite of ischemic stroke, systemic embolism, and death, whereas the primary safety outcome was a composite of major bleeding within a year of DOAC vs warfarin initiation. Treatment groups were compared in an under-treatment analysis using inverse probability of treatment weighting and Cox proportional hazards.

RESULTS

A total of 8899 included patients filled out a new oral anticoagulation therapy claim; 3335 for warfarin and 5564 for DOACs. Compared with warfarin, 15 mg and 20 mg rivaroxaban presented a similar effectiveness and safety composite risk. Apixaban 5.0 mg was associated with a lower effectiveness composite risk [Hazard ratio (HR) 0.76; 95% confidence interval (CI): 0.65-0.88] and a similar safety risk (HR 0.94; 95%CI: 0.66-1.35). Apixaban 2.5 mg was associated with a similar effectiveness composite (HR 1.00; 95%CI: 0.79-1.26) and a lower safety risk (HR 0.65; 95%CI: 0.43-0.99. Although, apixaban 5.0 mg was associated with a better effectiveness (HR 0.76; 95%CI: 0.65-0.88), but a similar safety risk profile (HR 0.94; 95%CI: 0.66-1.35). The observed improvement in the effectiveness composite for apixaban 5.0 mg was driven by a reduction in mortality (HR 0.61; 95%CI: 0.43-0.88).

CONCLUSION

In comparison with warfarin, rivaroxaban and apixaban appear to be effective and safe in AF patients with stage III CKD.

Kidney function and the comparative effectiveness and safety of direct oral anticoagulants vs. warfarin in adults with atrial fibrillation: a multicenter observational study

AIMS

The aim of this study was to determine the comparative effectiveness and safety of direct oral anticoagulants (DOACs) and warfarin in adults with atrial fibrillation (AF) by level of kidney function.

METHODS AND RESULTS

We pooled findings from five retrospective cohorts (2011-18) across Australia and Canada of adults with; a new dispensation for a DOAC or warfarin, an AF diagnosis, and a measure of baseline estimated glomerular filtration rate (eGFR). The outcomes of interest, within 1 year from the cohort entry date, were: (1) the composite of all-cause death, first hospitalization for ischaemic stroke, or transient ischaemic attack (effectiveness), and (2) first hospitalization for major bleeding defined as an intracranial, upper or lower gastrointestinal, or other bleeding (safety). Cox models were used to examine the association of a DOAC vs. warfarin with outcomes, after 1:1 matching via a propensity score. Kidney function was categorized as eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m2. A total of 74 542 patients were included in the matched analysis. DOAC initiation was associated with greater or similar effectiveness compared with warfarin initiation across all eGFR categories [pooled HRs (95% CIs) for eGFR categories: 0.74(0.69-0.79), 0.76(0.54-1.07), 0.68(0.61-0.75) and 0.86(0.76-0.98)], respectively. DOAC initiation was associated with lower or similar risk of major bleeding than warfarin initiation [pooled HRs (95% CIs): 0.75(0.65-0.86), 0.81(0.65-1.01), 0.82(0.66-1.02), and 0.71(0.52-0.99), respectively). Associations between DOAC initiation, compared with warfarin initiation, and study outcomes were not modified by eGFR category.

CONCLUSION

DOAC use, compared with warfarin use, was associated with a lower or similar risk of all-cause death, ischaemic stroke, and transient ischaemic attack and also a lower or similar risk of major bleeding across all levels of kidney function.

The Safety of Direct Oral Anticoagulants Compared to Warfarin in Patients Hospitalized With Acute Kidney Injury

BACKGROUND

Direct oral anticoagulants (DOACs) are preferred over warfarin for many indications, though their safety has not been well established in patients with acute renal impairment.

OBJECTIVE

The purpose of this study was to evaluate the frequency of bleeding complications associated with DOACs compared with warfarin in patients admitted to the hospital with acute kidney injury (AKI).

METHODS

This was a retrospective cohort study evaluating patients admitted to the Penn Medicine Lancaster General Hospital with a diagnosis of AKI from October 2017 through September 2021 and receiving therapy with oral anticoagulants. Comparing DOACs with warfarin, the primary endpoint was the percent frequency of composite major and minor bleeding during the admission and within 30 days of discharge.

RESULTS

There were 112 hospitalization encounters included in the study. Of these, 42 (37.5%) patients were receiving warfarin and 70 (62.5%) patients were receiving DOAC therapy before admission. There was a higher frequency of the primary endpoint of bleeding in patients receiving DOACs as compared with warfarin, though this was not statistically significant (18.5% vs. 11.9%, respectively, P = 0.432). There were no differences between groups in the frequency of major bleeding, minor bleeding, or transfusions. Patients receiving DOAC therapy were more likely to experience anticoagulation-related readmissions or emergency department visits compared with patients on warfarin therapy (11.4% vs. 0%, P = 0.024).

CONCLUSION AND RELEVANCE

Direct oral anticoagulants and warfarin were associated with statistically similar rates of bleeding in patients presenting with AKI. Further research is necessary to elucidate if DOACs are safer than warfarin in this patient population.

Safety and Effectiveness of Rivaroxaban Versus Warfarin Across GFR Levels in Atrial Fibrillation: A Population-Based Study in Australia and Canada

Rationale & Objective

The benefit-risk profile of rivaroxaban versus warfarin for atrial fibrillation (AF) in patients with chronic kidney disease is uncertain. We compared rivaroxaban with warfarin across the range of kidney function in adults with AF.

Study Design

Multicenter retrospective cohort.

Setting & Participants

Adults with AF and a measure of estimated glomerular filtration rate (eGFR); using administrative data from 5 jurisdictions across Australia and Canada (2011-2018). Kidney function was categorized as eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m². Patients receiving dialysis and kidney transplant recipients were excluded.

Exposures

New dispensation of either rivaroxaban or warfarin.

Outcomes

Composite (1) effectiveness outcome (all-cause death, ischemic stroke, or transient ischemic attack) and (2) major bleeding events (intracranial, gastrointestinal, or other) at 1 year.

Analytical Approach

Cox proportional hazards models accounting for propensity score matching were performed independently in each jurisdiction and then pooled using random-effects meta-analysis.

Results

55,568 patients (27,784 rivaroxaban-warfarin user matched pairs; mean age 74 years, 46% female, 33.5% with eGFR <60 mL/min/1.73 m²) experienced a total of 4,733 (8.5%) effectiveness and 1,144 (2.0%) bleeding events. Compared to warfarin, rivaroxaban was associated with greater or similar effectiveness across a broad range of kidney function (pooled HRs of 0.72 [95% CI, 0.66-0.78], 0.78 [95% CI, 0.58-1.06], 0.70 [95% CI, 0.57-0.87], and 0.78 [95% CI, 0.62-0.99]) for eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m², respectively). Rivaroxaban was also associated with similar risk of major bleeding across all eGFR categories (pooled HRs of 0.75 [95% CI, 0.56-1.00], 1.01 [95% CI, 0.79-1.30], 0.87 [95% CI, 0.66-1.15], and 0.63 [95% CI, 0.37-1.09], respectively).

Limitations

Unmeasured treatment selection bias and residual confounding.

Conclusions

In adults with AF, rivaroxaban compared with warfarin was associated with lower or similar risk of all-cause death, ischemic stroke and transient ischemic attack and similar risk of bleeding across a broad range of kidney function.

Plain-Language Summary

This real-world study involved a large cohort of 55,568 adults with atrial fibrillation from 5 jurisdictions across Australia and Canada. It showed that the favorable safety (bleeding) and effectiveness (stroke or death) profile of rivaroxaban compared with warfarin was consistent across different levels of kidney function. This study adds important safety data on the use of rivaroxaban in patients with reduced kidney function, including those with estimated glomerular filtration rate <30 mL/min/1.73 m² in whom the risks and benefits of rivaroxaban use is most uncertain. Overall, the study supports the use of rivaroxaban as a safe and effective alternative to warfarin for atrial fibrillation across differing levels of kidney function.

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.

Non-valvular Atrial Fibrillation in CKD: Role of Vitamin K Antagonists and Direct Oral Anticoagulants. A Narrative Review

Atrial fibrillation (AF) is the most common arrhythmia in chronic kidney disease (CKD), with a close bidirectional relationship between the two entities. The presence of CKD in AF increases the risk of thromboembolic events, mortality and bleeding. Vitamin K antagonists (VKA) have been the mainstay of treatment for the prevention of thromboembolic events in AF until recently, with confirmed benefits in AF patients with stage 3 CKD. However, the risk-benefit profile of VKA in patients with AF and stages 4-5 CKD is controversial due to the lack of evidence from randomized controlled trials. Treatment with VKA in CKD patients has been associated with conditions such as poorer anticoagulation quality, increased risk of bleeding, faster progression of vascular/valvular calcification and higher risk of calciphylaxis. Direct oral anticoagulants (DOACs) have shown equal or greater efficacy in stroke/systemic embolism prevention, and a better safety profile than VKA in post-hoc analysis of the pivotal randomized controlled trials in patients with non-valvular AF and stage 3 CKD, yet evidence of its risk-benefit profile in more advanced stages of CKD is scarce. Observational studies associate DOACs with a good safety/effectiveness profile compared to VKA in non-dialysis CKD patients. Further, DOACs have been associated with a lower risk of acute kidney injury and CKD development/progression than VKA. This narrative review summarizes the evidence of the efficacy and safety of warfarin and DOACs in patients with AF at different CKD stages, as well as their effects on renal function, vascular/valvular calcification and bone health.

Utilization and long-term persistence of direct oral anticoagulants among patients with nonvalvular atrial fibrillation and liver disease

AIMS

We characterized the utilization and long-term treatment persistence of direct oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation (NVAF) and liver disease.

METHOD

Using the UK Clinical Practice Research Datalink, we assembled a population-based cohort of NVAF patients with liver disease initiating oral anticoagulants between 2011 and 2020. Logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs) of the association between patient characteristics and initiation of DOACs vs vitamin K antagonists (VKAs). Cox proportional hazards models estimated hazard ratios (HRs) and 95% CIs of the association between patient characteristics and the switch from VKAs to DOACs vs remaining on VKAs. We also assessed the 5-year treatment persistence with DOACs vs VKAs, and whether ischemic stroke or bleeding preceded treatment discontinuation.

RESULTS

Our cohort included 3167 NVAF patients with liver disease initiating DOACs (n = 2247, 71%) or VKAs (n = 920, 29%). Initiators of DOACs were more likely to have prior ischemic stroke (OR 1.44, 95% CI 1.12-1.85) than VKA initiators but less likely to have used antiplatelet agents (OR 0.66, 95% CI 0.53-0.82). Patients switching to DOACs were more likely to have used selective serotonin reuptake inhibitors (HR 1.64, 95% CI 1.13-2.37) than those remaining on VKAs. At 5 years, 31% of DOAC initiators and 9% of VKA initiators remained persistent. Only few patients were diagnosed with ischemic stroke or bleeding prior to treatment discontinuation.

CONCLUSION

Most NVAF patients with liver disease initiated treatment with DOACs. Long-term persistence with DOACs was higher than with VKAs but remained relatively low.

Real-world comparison of direct-acting oral anticoagulants and vitamin K antagonists in chronic kidney disease: a systematic review and meta-analysis

Background: No clear clinical guidelines exist on anticoagulant use for chronic kidney disease (CKD) patients. We compared the efficacy and safety of direct-acting oral anticoagulants (DOACs) vs. vitamin K antagonists (VKA) in patients with CKD by pooling data from real-world observational studies.Research design & methods: This systematic review searched PubMed, Embase, and CENTRAL databases and pooled multivariable-adjusted hazard ratios (HR) of outcomes.Results: Fifteen studies were included. Our results indicated a small but significant reduction in the risk of all-cause mortality (p = 0.01), stroke or systemic embolism (p = 0.03), and major bleeding (p = 0.01) with DOAC as compared to VKA. In subgroup analysis based on the severity of CKD, no difference in the risk of stroke or systemic embolism was noted in any subgroups. The risk of mortality was reduced only in patients with moderate-severe or severe CKD and the risk of major bleeding was reduced only in patients with moderate-severe or moderate CKD.Conclusion: DOACs are associated with only a modest reduction in stroke or systemic embolism, major bleeding, and mortality when compared to VKA in CKD patients. Reduction in mortality and major bleeding with DOAC may only be seen in moderate-to-severe CKD patients.

Outcomes in VKA-treated patients with atrial fibrillation and chronic kidney disease: Clinical trials vs 'real-world'

BACKGROUND

Our objectives were to evaluate the risk of adverse events in a 'real-world' vs 'clinical trial' cohort of atrial fibrillation (AF) patients with chronic kidney disease (CKD).

METHODS

We studied patient-level data for vitamin K antagonist-treated AF patients with a creatinine clearance <60 mL/min from the Murcia AF Project and AMADEUS trial. The study end-points were ischaemic stroke, major bleeding, all-cause mortality, myocardial infarction and intracranial haemorrhage.

RESULTS

This study included 1,108 AF patients with CKD. The annual rate of the composite study outcome of ischaemic stroke, major bleeding and all-cause mortality was higher in the real-world (13.4%) vs AMADEUS (6.6%) cohort with an IRR of 2.04 (95% CI,1.34-3.09), P < .001. Individual annual rates of major bleeding, all-cause mortality and non-cardiovascular mortality were significantly greater in the real-world cohort. Similar findings were demonstrated even after multivariable adjustment, with the composite outcome HR of 2.85 (95% CI,1.74-4.66), P < .001. In a propensity score matched cohort, this risk remained significantly higher in the real-world cohort (IRR 2.95 [95% CI,1.03-10.28], P = .027), as did the risk of major bleeding and all-cause mortality.

CONCLUSION

Vitamin K antagonist-treated AF patients with CKD are exposed to significant annual rates of major adverse events including all-cause mortality. This risk may be under-appreciated in the idealised environment of randomised controlled trials.

Analysis of the Introduction in Clinical Practice of New Oral Anticoagulants in Local Health Agency BT: Translation of the Clinical Trial Data to a Local Health Care Area

The commercial release of the New Oral Anticoagulants (NOACs) has been the most significant change in anticoagulant therapy in recent years. The work aimed to evaluate the economic and health impact for the Local Health Agency Barletta-Andria-Trani (BT). Through the Regional Information System data about naïve patients on NOAC treatment and patients on anti-vitamin-k (VKA), treatments were extrapolated. We assessed therapeutic continuity, pharmaceutical expenditure, hospitalizations, and deaths in 2017 and 2018. Therapeutic continuity was similar in the two groups. The number and the average cost of hospitalizations for a patient treated with VKAs were almost constant, while those of patients treated with NOACs decreased. The treatment of adult-aged naïve patients with NOACs, compared to VKAs therapy, involves an increase in expenditure of about 100€ for a patient, but the reduced hospitalizations could generate, in the long term, saving for the Health System. Clinical data, according to the Real-World Data, confirmed the safety and effectiveness of these drugs. However, attention to the special population is necessary to improve the safety and effectiveness of NOACs. Innovative formulations for pediatric patients are being developed. The challenge for Health Systems is the appropriate use of available resources through health interventions with transversal competences.

Real-world data on the incidence, mortality, and cost of ischaemic stroke and major bleeding events among non-valvular atrial fibrillation patients in England

RATIONALE, AIMS, AND OBJECTIVES

Several novel oral anticoagulants (NOACs) are licensed for atrial fibrillation (AF) treatment in the United Kingdom. We describe the incidence and mortality from ischaemic stroke and major bleeding in non-valvular atrial fibrillation (NVAF) patients in England, including treatment patterns before/following introduction of NOACs, healthcare resource utilization (HRU), and costs post-onset of these events.

METHOD

Data were extracted from the UK Clinical Practice Research Datalink linked to Hospital Episode Statistics secondary care and Office for National Statistics mortality data.

RESULTS

Of 42 966 patients with a first AF record between 2011 and 2016, 9143 patients (21.3%) remained without AF (antiplatelets/antithrombotics) treatment post-index diagnosis. The proportion of patients receiving aspirin for ≥3 months post-index declined during the study (50.6%-5.5%), irrespective of CHA₂ DS₂ -VASc score, while the proportion prescribed NOACs increased (2.0%-70.1%). Rates of ischaemic stroke per 1000 patient-years (95% CI) were 9.4 (3.8-15.0) with NOACs, 10.4 (8.0-12.9) with warfarin, 20.1 (16.4-23.8) with aspirin, 21.3 (5.3-37.2) with other antiplatelets and 43.6 (39.3-47.8) in patients without AF prescription. Major bleeding occurred at a similar rate with different treatments. All-cause mortality rates were 42.8 (31.4-54.3) with NOACs, 46.3 (41.1-51.5) with warfarin, 56.5 (50.5-62.4) with aspirin, 102.2 (76.2-128.3) with other antiplatelets and 412.8 (399.6-426.0) with no AF prescription. Mean annual National Health Service healthcare costs up to 1 year post-index were lowest in patients receiving aspirin plus other antiplatelets without an event (£6152), and highest in patients with an event without AF prescriptions (£17 957). By extrapolation, national AF HRU in the United Kingdom in 2016 was estimated at £8-16 billion annually.

CONCLUSIONS

These data provide temporal insights into AF treatment patterns and outcomes for NVAF patients in England and highlight the need to review higher stroke risk AF patients not receiving antiplatelet/antithrombotic prescriptions.

Comparative effectiveness and safety of direct oral anticoagulants versus warfarin in UK patients with atrial fibrillation and type 2 diabetes: A retrospective cohort study

PURPOSE

To estimate the effectiveness and safety of direct oral anticoagulants (DOACs) compared with warfarin in AF patients with type 2 diabetes (T2DM).

METHODS

A retrospective cohort study was designed, using the UK Clinical Practice Research Datalink (August 2011-June 2018). Participants were 1-year naïve users of DOACs or warfarin, followed from the date of first prescription of an oral anticoagulant until the end of the study period, death, discontinuation of treatment, switching to another anticoagulant, or an outcome of interest, whichever came first. Cox regression analysis was performed to estimate the hazard ratio (HR) adjusted for potential confounders.

RESULTS

A total of 8555 patients were identified. No significant differences were found between DOACs and warfarin in the risk of stroke (adjusted HR 1.15; 95% CI 0.82-1.60), ischemic and unspecified stroke (adjusted HR 1.23; 95% CI 0.86-1.76) or haemorrhagic stroke (adjusted HR 0.75; 95% CI 0.30-1.85), and myocardial infarction (adjusted HR 1.39;95% CI 0.99-1.97). DOAC and warfarin users were comparable with respect to risk of major bleed (adjusted HR 0.83; 95% CI 0.68-1.03), intracranial bleeding (HR 0.66; 95% CI 0.34-1.30), gastrointestinal bleeding (HR 0.88; 95% CI 0.60-1.30), and bleeding on other clinically relevant sites (HR 0.89; 95% CI 0.60-1.31). In the subgroup analyses stratified by gender and diabetes severity, the risk for stroke and bleeding remained consistent.

CONCLUSION

DOACs are effective and safe alternatives to warfarin for the prevention of stroke in AF patients with T2DM.

Direct oral anticoagulants in chronic kidney disease: an update

PURPOSE OF REVIEW

Direct oral anticoagulants (DOACs) are variably eliminated by the kidneys rendering their use potentially problematic in patients with chronic kidney disease (CKD) or necessitating appropriate dose adjustment.

RECENT FINDINGS

Both observational and limited randomized trial data for DOACs compared with no treatment or with warfarin for patients with atrial fibrillation on maintenance dialysis were recently published. In a randomized trial in patients on hemodialysis, there was no significant difference in vascular calcification between patients who received rivaroxaban with or without vitamin K2 or vitamin K antagonists. A randomized trial of apixaban versus warfarin was terminated owing to poor enrollment and preliminary results identified no difference in clinical outcomes between groups. However, valuable pharmacodynamic data will be forthcoming from that trial. In observational research, among patients newly diagnosed with atrial fibrillation, there were opposing trends in the associations of apixaban initiation versus no oral anticoagulation with ischemic versus hemorrhagic stroke and no association was present with the overall risk of stroke or embolism. In another study comparing apixaban with warfarin initiation, apixaban was associated with less bleeding. Regular-dose apixaban (5 mg twice daily) associated with reduced rates of ischemic stroke or systemic embolism, whereas no such association was present for those prescribed the reduced dose (2.5 mg twice daily).

SUMMARY

DOACs may be used after appropriate dose adjustment for an established clinical indication in patients with advanced CKD. Quality evidence for oral anticoagulation, with any specific agent or dose, for stroke prevention in hemodialysis continues to be lacking.

Direct-Acting Oral Anticoagulants Versus Warfarin in Medicare Patients With Chronic Kidney Disease and Atrial Fibrillation

Background and Purpose:

The comparative effectiveness of direct-acting oral anticoagulants, compared with warfarin, for risks of stroke/systemic embolism, major bleeding, or death have not been studied in Medicare beneficiaries with atrial fibrillation and nondialysis-dependent chronic kidney disease.

Methods:

Medicare data from 2011 to 2017 were used to identify patients with stages 3, 4, or 5 chronic kidney disease and new atrial fibrillation who received a new prescription for warfarin, apixaban, rivaroxaban, or dabigatran. We estimated marginal hazard ratios with 95% CIs for the association of each direct-acting oral anticoagulant, compared with warfarin, for the outcomes of interest using inverse-probability-of-treatment weighted Cox proportional hazards models in as-treated and intention-to-treat analyses.

Results:

A total of 22 739 individuals met criteria (46.3% warfarin, 29.6% apixaban, 17.2% rivaroxaban, 6.9% dabigatran). Across the groups of anticoagulant users, mean age was 78.4 to 79.0 years; 50.3% to 51.4% were women, and 80.3% to 82.8% had stage 3 chronic kidney disease. In the as-treated analysis, for stroke/systemic embolism, hazard ratios, all compared with warfarin, were 0.70 (0.51–0.96) for apixaban, 0.80 (0.54–1.17) for rivaroxaban, and 1.15 (0.69–1.94) for dabigatran. For major bleeding, analogous hazard ratios were 0.47 (0.37–0.59) for apixaban, 1.05 (0.85–1.30) for rivaroxaban, and 0.95 (0.70–1.31) for dabigatran. There was no difference in the risk of all-cause mortality between the direct-acting oral anticoagulants and warfarin. Results of the intention-to-treat analysis were similar.

Conclusions:

Apixaban, compared with warfarin, was associated with decreased risk of stroke/systemic embolism and major bleeding; risks for both outcomes with rivaroxaban and dabigatran did not differ from risks with warfarin.

Real-world cost-effectiveness of rivaroxaban and apixaban vs VKA in stroke prevention in non-valvular atrial fibrillation in the UK

BACKGROUND

Morbidity and mortality associated with non-valvular atrial fibrillation (NVAF) imposes a substantial economic burden on the UK healthcare system.

OBJECTIVES

An existing Markov model was adapted to assess the real-world cost-effectiveness of rivaroxaban and apixaban, each compared with a vitamin K antagonist (VKA), for stroke prevention in patients with NVAF from the National Health Service (NHS) and personal and social services (PSS) perspective.

METHODS

The model considered a cycle length of 3 months over a lifetime horizon. All inputs were drawn from real-world evidence (RWE): baseline patient characteristics, clinical event and persistence rates, treatment effect (meta-analysis of RWE studies), utility values and resource use. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

The incremental cost per quality-adjusted life year was £14,437 for rivaroxaban, and £20,101 for apixaban, compared with VKA. The probabilities to be cost-effective compared with VKA were 90% and 81%, respectively for rivaroxaban and apixaban, considering a £20,000 threshold. In both comparisons, the results were most sensitive to clinical event rates.

CONCLUSIONS

These results suggest that rivaroxaban and apixaban are cost-effective vs VKA, based on RWE, considering a £20,000 threshold, from the NHS and PSS perspective in the UK for stroke prevention in patients with NVAF. This economic evaluation may provide valuable information for decision-makers, in a context where RWE is more accessible and its value more acknowledged.

Risk of Major Gastrointestinal Bleeding With New vs Conventional Oral Anticoagulants: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

There is controversy over whether use of non-vitamin K antagonist oral anticoagulants (NOACs) associates with increased risk of major gastrointestinal bleeding (GIB) compared with conventional therapies (such as vitamin K antagonists or anti-platelet agents). We performed a systematic review and meta-analysis of data from randomized controlled trials and high-quality real-world studies.

METHODS

We performed a systematic search of the MEDLINE, EMBASE, Cochrane Library, and ClinicalTrials.gov Website databases (through Oct 12, 2018) for randomized controlled trials and high-quality real-world studies that reported major GIB events in patients given NOACs or conventional therapy. Relative risks (RRs) for randomized controlled trials and adjusted hazard ratios (aHRs) for real-world studies were calculated separately using random-effects models.

RESULTS

We analyzed data from 43 randomized controlled trials (183,752 patients) and 41 real-world studies (1,879,428 patients). The pooled major rates of GIB for patients on NOACs (1.19%) vs conventional treatment (0.92%) did not differ significantly (RR from randomized controlled trials, 1.09; 95% CI, 0.91-1.31 and aHR from real-world studies, 1.02; 95% CI, 0.94-1.10; P_interaction=.52). Rivaroxaban, but not other NOACs, was associated with an increased risk for major GIB (RR from randomized controlled trials, 1.39; 95% CI, 1.17-1.65 and aHR from real-world studies, 1.14; 95% CI, 1.04-1.23; P_interaction = .06). Analyses of subgroups, such as patients with different indications, dosage, or follow-up time, did not significantly affect results. Meta-regression analysis failed to detect any potential confounding to impact the primacy outcome.

CONCLUSIONS

In a systematic review and meta-analysis of data from randomized controlled trials and real-world studies, we confirmed that there is no significant difference in risk of major GIB between patients receiving NOACs vs conventional treatment. Rivaroxaban users had a 39% increase in risk for major GIB.

Changing trends in the use of novel oral anticoagulants and warfarin for treating non-valvular atrial fibrillation

Background

Prevention of thromboembolism by novel oral anticoagulants is increasing, whilst use of vitamin K antagonists is on the decline. We assessed changes in the use of these anticoagulants in treating non-valvular atrial fibrillation between 2014 and 2018.

Methods

One-hundred and sixty-two consecutive patients (95 men, 67 women) with non-valvular atrial fibrillation, mean age 72.3 years (standard deviation = 11.0), underwent cardiac assessment in a single cardiac unit. Use of anticoagulants at the time of investigation was documented: overall 83 (51.2%) patients were prescribed novel oral anticoagulants and 79 (48.8%) warfarin treatment. Trends in treatment rates with either anticoagulant class over time were characterised by calculating the average annual percentage change using a Joinpoint Regression Program 4.7.0.0.

Results

There were diverging trends in anticoagulant treatment from 2014 to 2018 without join points: yearly increase in novel oral anticoagulant treatment (41.9, 45.5, 53.7, 53.1 and 72.7%, average annual percentage change = 16.2%, 95% confidence interval = 5.8% to 27.5%, p < 0.001), and decrease in warfarin treatment (57.1, 54.5, 46.3, 46.9 and 27.3%, average annual percentage change = −14.4%, 95% confidence interval = −25.2% to −2.1%, p < 0.001).

Conclusions

Changing trends in treatment with anticoagulants for patients with non-valvular atrial fibrillation observed within less than two years provide important information to healthcare services to estimate future pharmaco-economic costs for such treatments.

Recent evidence for direct oral anticoagulants in chronic kidney disease

PURPOSE OF REVIEW

The direct oral anticoagulants (DOACs) have emerged as an effective and safe alternative to vitamin K antagonists (VKAs) for stroke and venous thromboembolism (VTE) prevention. However, patients with chronic kidney disease (CKD) experience an increase in the risk of both thromboembolism and bleeding, and the risk-benefit profile of DOACs, particularly in advanced CKD remains a source of ongoing debate. This review summarizes the recent evidence on the effects of DOACs in CKD across a range of clinical indications including newly emerging indications.

RECENT FINDINGS

Data on early-to-moderate stage CKD derived from pivotal randomized controlled trials in broader atrial fibrillation and VTE populations support the favorable risk-benefit ratio of DOACs compared with VKAs in patients in these groups. However, safety data from observational studies comparing DOACs with VKAs in patients with atrial fibrillation and CKD (moderate to advanced) have been conflicting. Recent trials have evaluated the efficacy of low-dose DOACs on major cardiovascular outcomes, showing promising risk-benefit ratios in high-risk populations with concurrent CKD.

SUMMARY

Current data on patients with CKD derived from trials in the broader population suggest that DOACs are an effective alternative to VKAs in patients with early-to-moderate stage CKD. However, studies on patients with advanced CKD are lacking. Further randomized controlled trials, particularly those evaluating the risk of any clinically relevant bleeding as part of a more accurate assessment of the risk-benefit profile of DOACs in people with CKD, are needed.

Translating claims-based CHA2 DS2 -VaSc and HAS-BLED to ICD-10-CM: Impacts of mapping strategies

PURPOSE

The CHA₂ DS₂ -VaSc and HAS-BLED risk scores are commonly used in the studies of oral anticoagulants (OACs). The best ways to map these scores to the International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) codes is unclear, as is how they perform in various types of OAC users. We aimed to assess the distributions of CHA₂ DS₂ -VaSc and HAS-BLED scores and C-statistics for outcome prediction in the ICD-10-CM era using different mapping strategies.

METHODS

We compared the distributions of CHA₂ DS₂ -VaSc and HAS-BLED scores from various mapping strategies in atrial fibrillation patients before, during, and after ICD-10-CM transition. We estimated the C-statistics predicting the 90-day risk of hospitalized stroke (for CHA₂ DS₂ -VaSc) or hospitalized bleeding (for HAS-BLED) in patients identified at least 6 months after the ICD-10-CM transition, overall and by anticoagulant type.

RESULTS

Forward-backward mapping produced higher CHA₂ DS₂ -VaSc and HAS-BLED scores in the ICD-10-CM era compared to the ICD-9-CM era: the mean difference was 0.074 (95% confidence interval 0.064-0.085) for CHA₂ DS₂ -VaSc and 0.055 (0.048-0.062) for HAS-BLED. Both scores had higher C-statistics in patients taking no OACs (0.697 [0.677-0.717] for CHA₂ DS₂ -VaSc; 0.719 [0.702-0.737] for HAS-BLED) or direct OACs (0.695 [0.654-0.735] for CHA₂ DS₂ -VaSc; 0.700 [0.673-0.728] for HAS-BLED) than those taking warfarin (0.655 [0.613-0.697] for CHA₂ DS₂ -VaSc; 0.663 [0.6320.695] for HAS-BLED).

CONCLUSIONS

Existing mapping strategies generally preserved the distributions of CHA₂ DS₂ -VaSc and HAS-BLED scores after ICD-10-CM transition. Both scores performed better in patients on no OACs or direct OACs than patients on warfarin.

Use of oral anticoagulants in older people with atrial fibrillation in UK general practice: protocol for a cohort study using the Clinical Practice Research Datalink (CPRD) database

INTRODUCTION

Warfarin has frequently been underused in older people for stroke prevention in atrial fibrillation (AF). Direct oral anticoagulants (DOACs) entered the UK market from 2008 and have been recommended as an alternative to warfarin. This study aimed to describe any changes in the prescribing of oral anticoagulants (OACs) to people aged ≥75 years in UK general practice before and after the introduction of DOACs, to examine differences in patient characteristics which may influence prescribers' decisions regarding anticoagulation, to evaluate the time people stay on OACs and switching between OACs.

METHODS AND ANALYSIS

A retrospective cohort study design will be used. Patients with a diagnosis of AF will be identified from the Clinical Practice Research Datalink (CPRD). The study period will run from 1 January 2003 to 27 December 2017. Patients enter the cohort at the latest date of the start of the study period, first AF diagnosis, 75th birthday or a year from when they started to contribute research standard data. Follow-up continues until they leave the practice, death, the date the practice stops contributing research standard data or the end of the study period (27 December 2017). Exposure to OACs will be defined as ≥1 prescription issued for an OAC of interest during the study period. Patients issued an OAC in the year preceding study entry will be defined as 'prevalent users'. Patients starting on an OAC during the study period will be defined as 'incident users'. Incidence and prevalence of OAC prescribing, patient demographics and characteristics will be described during three time periods: 2003-2007, 2008-2012 and 2013-2017. Persistence (defined as the time from initiation to discontinuation of medication) with and switching between different OACs will be described.

ETHICS AND DISSEMINATION

The protocol for this study was approved by the CPRD Independent Scientific Advisory Committee. The results will be disseminated in a peer-reviewed journal and at conferences.

TRIAL REGISTRATION NUMBER

EUPAS29923.

Real-world 2-year outcome of atrial fibrillation treatment with dabigatran, apixaban, and rivaroxaban in patients with and without chronic kidney disease

Patients with non-valvular atrial fibrillation (NVAF) and chronic kidney disease (CKD) are at increased risk of stroke and bleeding. Although direct oral anticoagulant (DOAC) trials excluded patients with severe CKD, a growing portion of CKD patients have been starting DOACs and limited data from real-world outcome in this high-risk setting are available. The INSigHT registry included 632 consecutive NVAF patients that started apixaban (256 patients, 41%), dabigatran (245, 39%) and rivaroxaban (131, 20%) between 2012 and 2015. Based on creatinine clearance, two sub-cohorts were defined: (1) non-CKD group (CrCl 60-89 mL/min, 413 patients) and (2) CKD group (15-59 ml/min, 219). Compared to non-CKD patients, those with CKD, were at higher ischemic (CHA₂DS₂-VASc 4.5 vs 2.9, p < 0.001) and hemorrhagic risk (HAS-BLED 2.4 vs 1.8, p < 0.001). At 2-year follow-up, the overall ISTH-major bleeding and thromboembolic event rates were 5.2% and 2.3% and no significant difference between non-CKD and CKD patients for both efficacy and safety endpoints were observed. In non-CKD patients, the 2-year ISTH-major bleeding rates were higher in rivaroxaban group (HR 2.9, 95% CI 1.1-7.3; p = 0.047) while dabigatran showed non-significant excess in thromboembolic events (HR 4.3, 95% CI 0.9-20.8; p = 0.068). In CKD patients, a significantly higher rate of thromboembolic events was observed in rivaroxaban (HR 6.3, 95% CI 1.1-38.1; p = 0.044). This real-world, non-insurance database registry shows remarkable 2-year safety and efficacy profile of DOACs even in patients with moderate to severe CKD. Head to head differences between DOACs are exploratory, hypothesis generating and warrant further investigation in larger studies.

Oral anticoagulation in patients with chronic kidney disease

Objective

Data regarding the efficacy and safety of warfarin and non-vitamin K antagonist oral anticoagulant (NOAC) among patients with chronic kidney disease (CKD) remain scarce.

Methods

Systematic review and meta-analysis of studies involving patients with CKD treated with oral anticoagulants were conducted to evaluate the following outcomes: ischemic stroke, intracerebral hemorrhage (ICH), combined ischemic and hemorrhagic stroke (strokecombined), stroke or systemic embolism, mortality, and major bleeding events. CKD was defined based on creatinine clearance (CrCl) ranging from mild (CrCl: 60–89 mL/min), moderate (CrCl: 30–59 mL/min), to severe (CrCl: 15–29 mL/min).

Results

Fifteen studies (7 comparing NOAC vs warfarin and 8 comparing warfarin vs no anticoagulant) were identified comprising 78,053 patients. Warfarin (vs no anticoagulant) was associated with reduced risk of ischemic stroke (risk ratio [RR] = 0.68; 95% confidence interval [CI] 0.55–0.84]) and mortality (RR = 0.70; 95% CI 0.62–0.78). In comparison to warfarin, NOAC use lowered the risk of ICH (RR = 0.43; 95% CI 0.33–0.56), strokecombined (RR = 0.83; 95% CI 0.72–0.96), stroke or systemic embolism (RR = 0.73; 95% CI 0.62–0.85), and major bleeding (RR = 0.77; 95% CI 0.66–0.90). In adjusted analyses, warfarin use (vs no anticoagulant) was associated with reduced mortality (HRadj = 0.68; 95% CI 0.61–0.76), whereas NOAC (vs warfarin) use reduced the risk of ICH (HRadj = 0.39; 95% CI 0.30–0.50) and stroke or systemic embolism (HRadj = 0.75; 95% CI 0.65–0.88). Our sensitivity analyses comparing different NOACs exhibited that factor Xa inhibitors (compared to warfarin) consistently reduced strokecombined (RR = 0.84; 95% CI 0.73–0.96), mortality (RR = 0.84; 95% CI 0.70–1.00), ICH (RR = 0.45; 95% CI 0.24–0.85), and major bleeding (RR = 0.76; 95% CI 0.64–0.91).

Conclusions

Among patients with CKD treated with oral anticoagulants, NOACs present with a more favorable safety and efficacy profile for various cardiovascular outcomes.

Safety of direct oral anticoagulants in real-world clinical practice: translating the trials to everyday clinical management

INTRODUCTION

Direct oral anticoagulants (DOACs) may be regarded as some of the most successful innovations in recent times. These drugs which were specifically developed to overcome the challenges posed by warfarin did just that and in the process, have changed the outlook towards stroke prevention with anticoagulation. The decade of experience with these drugs that has resulted in the availability of large scale data on their safety profile has aided this. Areas covered: This review examines existing real-world studies (RWS) and their interpretation to better appreciate how they either complement or contradict findings from the hallmark trials. Specific focus has been made on the safety of DOACs, on their risks of major bleeding, intra-cranial haemorrhage (ICH), gastro-intestinal (GI) bleeding and all-cause mortality compared to warfarin and each other. DOAC use in the elderly and other sub-groups are briefly discussed. Expert opinion: Results for safety outcomes according to 'real world evidence' (RWE) are in-keeping with randomised controlled trials (RCTs) and currently, all 4 DOACs have been deemed at least as effective as warfarin, while demonstrating superiority in some aspects. While real world studies act as a complementary source of knowledge, traditional RCTs remain the gold standard for determining cause-effect relationships.