Direct oral anticoagulants in atrial fibrillation: can data from randomized clinical trials be safely transferred to the general population? No

Clinical outcomes in patients with atrial fibrillation treated with DOACs in a specialized anticoagulation center: Critical appraisal of real-world data

AIMS

Direct oral anticoagulants (DOAC) are progressively replacing vitamin K antagonists in the prevention of thromboembolism in patients with atrial fibrillation. However, their real-world clinical outcomes appear to be contradictory, with some studies reporting fewer and others reporting higher complications than the pivotal randomized controlled trials. We present the results of a clinical model for the management of DOACs in real clinical practice and provide a review of the literature.

METHODS

The MACACOD project is an ongoing, observational, prospective, single-center study with unselected patients that focuses on rigorous DOAC selection, an educational visit, laboratory measurements, and strict follow-up.

RESULTS

A total of 1,259 patients were included. The composite incidence of major complications was 4.93% py in the whole cohort vs 4.49% py in the edoxaban cohort. The rate of all-cause mortality was 6.11% py for all DOACs vs 5.12% py for edoxaban. There weren't differences across sex or between Edoxaban reduced or standard doses. However, there were differences across ages, with a higher incidence of major bleeding complications in patients >85 years (5.13% py vs 1.69% py in <75 years).

CONCLUSIONS

We observed an incidence of serious complications of 4.93% py, in which severe bleeding predominated (3.65% py). Considering our results, more specialized attention seems necessary to reduce the incidence of severe complications and also a more critical view of the literature. Considering our results, and our indirect comparison with many real-world studies, more specialized attention seems necessary to reduce the incidence of severe complications in AF patients receiving DOACs.

Awareness, Knowledge, and Utility of RCT Data vs RWE: Results From a Survey of US Cardiologists: Real-world Evidence in Clinical Decision Making

Real-world evidence (RWE) provides a potential rich source of additional information to the body of data available from randomized clinical trials (RCTs), but there is a need to understand the strengths and limitations of RWE before it can be applied to clinical practice. To gain insight into current thinking in clinical decision making and utility of different data sources, a representative sampling of US cardiologists selected from the current, active Fellows of the American College of Cardiology (ACC) were surveyed to evaluate their perceptions of findings from RCTs and RWE studies and their application in clinical practice. The survey was conducted online via the ACC web portal between 12 July and 11 August 2017. Of the 548 active ACC Fellows invited as panel members, 173 completed the survey (32% response), most of whom were board certified in general cardiology (n = 119, 69%) or interventional cardiology (n = 40, 23%). The survey results indicated a wide range of familiarity with and utilization of RWE amongst cardiologists. Most cardiologists were familiar with RWE and considered RWE in clinical practice at least some of the time. However, a significant minority of survey respondents had rarely or never applied RWE learnings in their clinical practice, and many did not feel confident in the results of RWE other than registry data. These survey findings suggest that additional education on how to assess and interpret RWE could help physicians to integrate data and learnings from RCTs and RWE to best guide clinical decision making.

Direct Oral Anticoagulants in Patients with Liver Disease in the Era of Non-Alcoholic Fatty Liver Disease Global Epidemic: A Narrative Review

Atrial fibrillation (AF) and venous thromboembolism (VTE) are highly prevalent and relevant healthcare issues. Direct oral anticoagulants (DOACs) are now the first-choice for anticoagulant treatment of these conditions displaying a better efficacy/safety profile than vitamin-K antagonists, mainly due to significantly reduced risk of major bleeding, especially of intracranial haemorrhage. Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in developed countries showing a continuously growing prevalence. Nonalcoholic steatohepatitis (NASH), its evolutive form, will be the leading cause for liver transplantation by 2020. NAFLD is independently associated with an increased risk of abnormalities of cardiac structure and function, including cardiac rhythm disorders (mainly AF). Moreover, data suggest an increased risk of unprovoked VTE associated with NAFLD/NASH. Therefore, a growing number of patients with chronic liver disease (CLD) will be candidate for anticoagulant therapy in the near future. Cirrhosis of any etiology is characterized by an unstable thrombosis/bleeding haemostatic balance, making anticoagulant therapy particularly challenging in this condition. Given that patients with significant active liver disease and cirrhosis were excluded from all pivotal randomized controlled trials on DOACs, this comprehensive review aims at critically discussing real-world evidence, including the latest population studies, regarding the use of DOACs in patients with CLD/cirrhosis.

Comparison Between Aspirin and Clopidogrel in Secondary Stroke Prevention Based on Real-World Data

Background

Clopidogrel was thought to be superior to aspirin for secondary prevention of vascular diseases in clinical trials. In this study we assessed the safety and efficacy of clopidogrel versus aspirin in real‐world practice by using the Taiwan Stroke Registry.

Methods and Results

Patients with ischemic stroke (2006–2016) on aspirin or clopidogrel for secondary stroke prevention were identified in the Taiwan Stroke Registry. Stroke recurrence and mortality rates in patients receiving aspirin (N=34 679) were compared with those receiving clopidogrel (N=7611) during a 12‐month follow‐up period. Propensity score matching and conditional Cox proportional hazards regression model were applied to control confounding factors with 6443 patients in each group. After propensity score matching, stroke recurrence rates were comparable between groups, with 223 patients in the aspirin (3.46%) and 244 in the clopidogrel group (3.79%) (hazard ratio=1.13, 95% confidence interval=0.89–1.43, P=0.311). However, the mortality rate was significantly higher in the clopidogrel group (362 patients, 5.62%) than in the aspirin group (302 patients, 4.69%) (hazard ratio=1.30, 95% confidence interval=1.07–1.58, P=0.008). Results were consistent before and after propensity score matching.

Conclusions

Clopidogrel was as effective as aspirin for prevention of recurrent stroke in real‐world practice. However, the mortality rate was significantly higher in the clopidogrel than in the aspirin group.

Differences in safety and efficacy of oral anticoagulants in patients with non-valvular atrial fibrillation: A Bayesian analysis

BACKGROUND

Novel oral anticoagulants are the cornerstone of therapy for non-valvular atrial fibrillation patients to lower the risk of ischaemic stroke. Given the lack of head-to-head comparisons among oral anticoagulants, a Bayesian analysis was used to evaluate their safety and efficacy based on studies from real-world practice.

METHODS

The PubMed, Embase, Cochrane and Web of Science databases were searched for relevant studies. Bayesian analyses were conducted to estimate hazard ratios (HR) and 95% credible intervals (CrI) for the safety and efficacy of oral anticoagulants.

RESULTS

In the 22 studies included in our analysis, novel oral anticoagulants exhibited a clear advantage over warfarin in preventing ischaemic stroke, haemorrhagic stroke and, especially, intracranial haemorrhage. Incidence of major bleeding was lowest for apixaban, followed by dabigatran, warfarin and rivaroxaban. Gastrointestinal bleeding risk was lowest for apixaban, followed by warfarin, and was slightly lower for dabigatran than for rivaroxaban with no statistical difference (HR 1.05, 95% CrI 0.99-1.11). Ischaemic stroke risk was lowest for rivaroxaban, followed by apixaban, dabigatran and warfarin (HR 1.13, 95% CrI 1.07-1.20).

CONCLUSION

In real-world practice, apixaban may represent the optimal treatment in terms of safety and efficacy for patients with non-valvular atrial fibrillation. For patients with high risk of ischaemic events but low bleeding risk, rivaroxaban may be preferable.

Guidelines on the management of atrial fibrillation in the emergency department: a critical appraisal

Several guidelines often exist on the same topic, sometimes offering divergent recommendations. For the clinician, it can be difficult to understand the reasons for this divergence and how to select the right recommendations. The aim of this study is to compare different guidelines on the management of atrial fibrillation (AF), and provide practical and affordable advice on its management in the acute setting. A PubMed search was performed in May 2014 to identify the three most recent and cited published guidelines on AF. During the 1-week school of the European School of Internal Medicine, the attending residents were divided in five working groups. The three selected guidelines were compared with five specific questions. The guidelines identified were: the European Society of Cardiology guidelines on AF, the Canadian guidelines on emergency department management of AF, and the American Heart Association guidelines on AF. Twenty-one relevant sub-questions were identified. For five of these, there was no agreement between guidelines; for three, there was partial agreement; for three data were not available (issue not covered by one of the guidelines), while for ten, there was complete agreement. Evidence on the management of AF in the acute setting is largely based on expert opinion rather than clinical trials. While there is broad agreement on the management of the haemodynamically unstable patient and the use of drugs for rate-control strategy, there is less agreement on drug therapy for rhythm control and no agreement on several other topics.

Comparative effectiveness of rivaroxaban in the treatment of nonvalvular atrial fibrillation

Rivaroxaban is a direct oral anticoagulant (DOAC) approved for the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation, a common arrhythmia. In this review, we summarize the effectiveness of rivaroxaban versus warfarin and the DOACs dabigatran, apixaban and edoxaban. The primary focus is on primary evidence from clinical trials, indirect comparison studies and real-world studies. While there are gaps in the literature, the evidence thus far indicates that rivaroxaban is superior to warfarin and similar to dabigatran, apixaban and edoxaban for the prevention of stroke or systemic embolism in patients with nonvalvular atrial fibrillation, although rivaroxaban may be associated with an elevated bleeding risk compared with other DOACs.

Risk-Benefit Profile of Direct-Acting Oral Anticoagulants in Established Therapeutic Indications: An Overview of Systematic Reviews and Observational Studies

Since 2008, the direct-acting oral anticoagulants (DOACs) have expanded the therapeutic options of cardiovascular diseases with recognized clinical and epidemiological impact, such as non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE), and also in the preventive setting of orthopedic surgical patients. The large body of evidence, not only from pivotal clinical trials but also from 'real-world' postmarketing observational findings (e.g. analytical epidemiological studies and registry data) gathered to date allow for a first attempt at verifying a posteriori whether or not the pharmacological advantages of the DOACs actually translate into therapeutic innovation, with relevant implications for clinicians, regulators and patients. This review aims to synthesize the risk-benefit profile of DOACs in the aforementioned consolidated indications through an 'evidence summary' approach gathering the existent evidence-based data, particularly systematic reviews with meta-analyses of randomized controlled trials, as well as observational studies, comparing DOACs with vitamin K antagonists. Clinical evidence will be discussed and compared with major international guidelines to identify whether an update is needed. Controversial clinically relevant safety issues will be also examined in order to highlight current challenges and unsettled questions (e.g. actual bleeding risk in susceptible populations). It is anticipated that the large number of publications on NVAF or VTE (44 systematic reviews with meta-analyses and 12 observational studies retained in our analysis) suggests the potential existence of overlapping studies and calls for common criteria to qualitatively and quantitatively assess discordances, thus guiding future research.