Comparing stroke prevention therapy of direct oral anticoagulants and vitamin K antagonists in patients with atrial fibrillation: a nationwide retrospective observational study

Performance of HAS-BLED and DOAC scores to predict major bleeding events in atrial fibrillation patients treated with direct oral anticoagulants: A report from a prospective European observational registry

BACKGROUND

The DOAC score has been recently proposed for bleeding risk stratification of patients with atrial fibrillation treated with direct oral anticoagulants (DOAC).

OBJECTIVE

To compare the performance of HAS-BLED and DOAC score in predicting major bleeding events in a contemporary cohort of European AF patients treated with DOAC.

METHODS

We included patients derived from a prospective observational registry of European AF patients. HAS-BLED and DOAC scores were calculated as per the original schemes. Our primary endpoint was major bleeding events. Receiver operating characteristic (ROC) curves were used to compare the predictive ability of the scores.

RESULTS

A total of 2834 AF patients (median age [IQR] 69 [62-77] years; 39.6 % female) treated with DOAC were included in the analysis. According to the HAS-BLED score, 577 patients (20.4 %) were categorized as very low risk of bleeding, as compared to 1276 (45.0 %) according to DOAC score. A total of 55 major bleeding events occurred with an overall incidence of 1.04 per 100 patient-years. Both scores showed only a modest ability for the prediction of bleeding events (HAS-BLED area under the curve [AUC], 0.65, 95 % confidence interval [CI] 0.55-0.70; DOAC score AUC 0.62, 95 % CI 0.59-0.71, p for difference = 0.332]. At calibration analysis, the DOAC score showed modest calibration, especially for patients at high risk, when compared to HAS-BLED.

CONCLUSION

In a contemporary cohort of DOAC-treated AF patients, both HAS-BLED and DOAC scores only modestly predicted the occurrence of major bleeding events. Our results do not support the preferential use of DOAC score over HAS-BLED.

Apixaban, edoxaban and rivaroxaban but not dabigatran are associated with higher mortality compared to vitamin-K antagonists: A retrospective German claims data analysis

BACKGROUND

Vitamin-K antagonists (VKAs) have widely been replaced by non-VKA oral anticoagulants (NOACs). This includes Austria, Germany and Switzerland, where as VKA, instead of warfarin, the much longer-acting phenprocoumon is used, which was not compared to NOACs in clinical trials.

METHODS

Using administrative data from a large German health insurance, we included all anticoagulation-naïve patients with a first prescription of a NOAC or VKA between 2012 and 2020. We analysed overall survival, major adverse cardiac and cerebrovascular events, major thromboembolic events and major bleeding.

RESULTS

Overall, 570,137 patients were included (apixaban: 26.9%, dabigatran: 4.6%, edoxaban: 8.8%, rivaroxaban: 39.1% and VKA: 20.7% of these 99.4% phenprocoumon). In the primary analysis using a 1:1 propensity score matching-cohort (PSM-cohort), a significantly higher overall mortality was found for apixaban, edoxaban and rivaroxaban (all p < 0.001) but not for dabigatran (p = 0.13) compared to VKA. In this PSM-cohort, 5-year mortality was 22.7% for apixaban versus 12.7% for VKA, 19.5% for edoxaban versus 11.4% for VKA, 16.0% for rivaroxaban versus 12.3% for VKA (all p < 0.001) and 13.0% for dabigatran versus 12.8% for VKA (p = 0.06). The observed effect was confirmed in sensitivity analyses using un-weighted and three different weighted Fine-Gray regression models on the basis of the entire cohort.

CONCLUSIONS

In this large real-world analysis, apixaban, edoxaban and rivaroxaban, but not dabigatran, were associated with worse survival compared to VKA. These findings, consistent with a few other studies including phenprocoumon, cast profound doubts on the unreflected, general use of NOACs. Randomized trials should assess whether phenprocoumon might actually be superior to NOACs.

2024 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2024 AHA Statistical Update is the product of a full year's worth of effort in 2023 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. The AHA strives to further understand and help heal health problems inflicted by structural racism, a public health crisis that can significantly damage physical and mental health and perpetuate disparities in access to health care, education, income, housing, and several other factors vital to healthy lives. This year's edition includes additional global data, as well as data on the monitoring and benefits of cardiovascular health in the population, with an enhanced focus on health equity across several key domains.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Safety outcomes of direct oral anticoagulants in older adults with atrial fibrillation: a systematic review and meta-analysis of (subgroup analyses from) randomized controlled trials

Balancing stroke prevention and risk of bleeding in patients with atrial fibrillation (AF) is challenging. Direct oral anticoagulants (DOACs) are by now considered standard of care for treating patients with AF in international guidelines. Our objective was to assess the safety of long-term intake of DOACs in older adults with AF. We included RCTs in elderly (≥ 65 years) patients with AF. A systematic search in MEDLINE and EMBASE was performed on 19 April 2022. For determination of risk of bias, the RoB 2 tool was applied. We pooled outcomes using random-effects meta-analyses. The quality of evidence was assessed using GRADE. Eleven RCTs with a total of 63,374 patients were identified. Two RCTs compared apixaban with either warfarin or aspirin, four edoxaban with either placebo, aspirin, or vitamin K antagonists (VKAs), two dabigatran with warfarin and three rivaroxaban with warfarin. DOACs probably reduce mortality in elderly patients with AF (HR 0.89 95%CI 0.77 to 1.02). Low-dose DOACs likely reduce bleeding compared to VKAs (HR ranged from 0.47 to 1.01). For high-dose DOACS the risk of bleeding varied widely (HR ranged from 0.80 to 1.40). We found that low-dose DOACs probably decrease mortality in AF patients. Moreover, apixaban and probably edoxaban are associated with fewer major or clinically relevant bleeding (MCRB) events compared to VKAs. For dabigatran and rivaroxaban, the risk of MCRB varies depending on dose. Moreover, subgroup analyses indicate that in the very old (≥ 85) the risk for MCRB events might be increased when using DOACs.Registration: PROSPERO: CRD42020187876.

Patients on vitamin K treatment: is switching to direct-acting oral anticoagulation cost-effective? A target trial on a prospective cohort

AIMS

Direct-acting oral anticoagulants (DOACs) have, to a substantial degree, replaced vitamin K antagonists (VKA) as treatments for stroke prevention in atrial fibrillation (AF) patients. However, evidence on the real-world causal effects of switching patients from VKA to DOAC is lacking. We aimed to assess the empirical incremental cost-effectiveness of switching patients to DOAC compared with maintaining VKA treatment.

METHODS

The target trial approach was applied to the prospective observational Swiss-AF cohort, which enrolled 2415 AF patients from 2014 to 2017. Clinical data, healthcare resource utilisation and EQ-5D-based utilities representing quality of life were collected in yearly follow-ups. Health insurance claims were available for 1024 patients (42.4%). Overall survival, quality-of-life, costs from the Swiss statutory health insurance perspective and cost-effectiveness were estimated by emulating a target trial in which patients were randomly assigned to switch to DOAC or maintain VKA treatment.

RESULTS

228 patients switching from VKA to DOAC compared with 563 patients maintaining VKA treatment had no overall survival advantage over a 5-year observation period (HR 0.99, 95% CI 0.45, 1.55). The estimated gain in quality-adjusted life years (QALYs) was 0.003 over the 5-year period at an incremental costs of CHF 23 033 (€ 20 940). The estimated incremental cost-effectiveness ratio was CHF 425 852 (€ 387 138) per QALY gained.

CONCLUSIONS

Applying a causal inference method to real-world data, we could not demonstrate switching to DOACs to be cost-effective for AF patients with at least 1 year of VKA treatment. Our estimates align with results from a previous randomised trial.

Gene polymorphism as a cause of hemorrhagic complications in patients with non-valvular atrial fibrillation treated with oral vitamin K-independent anticoagulants

Atrial fibrillation (AF) accounts for 40% of all cardiac arrhythmias and is associated with a high risk of stroke and systemic thromboembolic complications. Dabigatran, rivaroxaban, apixaban, and edoxaban are direct oral anticoagulants (DOACs) that have been proven to prevent stroke in patients with non-valvular AF. This review summarizes the pharmacokinetics, pharmacodynamics, and drug interactions of DOACs, as well as new data from pharmacogenetic studies of these drugs. This review is aimed at analyzing the scientific literature on the gene polymorphisms involved in the metabolism of DOACs. We searched PubMed, Cochrane, Google Scholar, and CyberLeninka (Russian version) databases with keywords: 'dabigatran', 'apixaban', 'rivaroxaban', 'edoxaban', 'gene polymorphism', 'pharmacogenetics', 'ABCB1', 'CES1', 'SULT1A', 'ABCG2', and 'CYP3A4'. The articles referred for this review include (1) full-text articles; (2) study design with meta-analysis, an observational study in patients taking DOAC; and (3) data on the single-nucleotide polymorphisms and kinetic parameters of DOACs (plasma concentration), or a particular clinical outcome, published in English and Russian languages during the last 10 years. The ages of the patients ranged from 18 to 75 years. Out of 114 reviewed works, 24 were found eligible. As per the available pharmacogenomic data, polymorphisms affecting DOACs are different. This may aid in developing individual approaches to optimize DOAC pharmacotherapy to reduce the risk of hemorrhagic complications. However, large-scale population studies are required to determine the dosage of the new oral anticoagulants based on genotyping. Information on the genetic effects is limited owing to the lack of large-scale studies. Uncovering the mechanisms of the genetic basis of sensitivity to DOACs helps in developing personalized therapy based on patient-specific genetic variants and improves the efficacy and safety of DOACs in the general population.

[Basics for the Use of Andexanet]

BACKGROUND

 For life-threatening or uncontrollable bleeding in association with the thrombin inhibitor dabigatran, the monoclonal antibody fragment idarucizumab is available, and for bleeding in association with the direct factor Xa inhibitors rivaroxaban or apixaban, the modified recombinant FXa protein andexanet is available for reversal. These antidotes represent emergency drugs that are typically used only after performing guideline-compliant multimodal measures.

METHODS

 An interdisciplinary group of experienced experts in the fields of angiology, hematology, internal medicine, clinical pharmacology, laboratory medicine, transfusion medicine, anesthesiology, intensive care, and hemostaseology developed recommendations relevant to daily clinical practice based on the current scientific evidence.

RESULTS

 Reversal of oral anticoagulants should be considered for severe bleeding in the following situations: (1) life-threatening bleeding or refractory hemorrhagic shock, (2) intracerebral bleeding, or (3) endoscopically unstoppable gastrointestinal bleeding. After successful hemostasis, anticoagulation (e.g., direct oral anticoagulant, vitamin K antagonist, and heparin) should be resumed promptly, taking into account individual bleeding and thromboembolic risk.

DISCUSSION

 This article aims to facilitate the management of patients with andexanet by all medical disciplines involved, thereby ensuring optimal care of patients during bleeding episodes.

Pharmacodynamic Drug-Drug Interactions and Bleeding Outcomes in Patients with Atrial Fibrillation Using Non-Vitamin K Antagonist Oral Anticoagulants: a Nationwide Cohort Study

PURPOSE

Pharmacodynamic drug-drug interactions (PD DDIs) may influence the safety of non-vitamin K antagonist oral anticoagulants (NOACs), but the extent to which PD DDIs increase bleeding risks, remains unclear. Therefore, the impact of PD DDIs on bleeding outcomes in NOAC-treated patients with atrial fibrillation (AF) was investigated.

METHODS

Using Belgian nationwide data, NOAC-treated AF patients were included between 2013-2019. Concomitant use of PD interacting drugs when initiating NOAC treatment was identified.

RESULTS

Among 193,072 patients, PD DDIs were identified in 114,122 (59.1%) subjects. After multivariable adjustment, concomitant use of PD interacting drugs was associated with significantly higher risks of major or clinically-relevant non-major bleeding (adjusted hazard ratio (aHR) 1.19, 95% confidence interval (CI) (1.13-1.24)), gastrointestinal (aHR 1.12, 95%CI (1.03-1.22)), urogenital (aHR 1.21, 95%CI (1.09-1.35)) and other bleeding (aHR 1.28, 95%CI (1.20-1.36)), compared to NOAC-treated AF patients without PD interacting drug use. Increased bleeding risks were most pronounced with P2Y12 inhibitors (aHR 1.62, 95%CI (1.48-1.77)) and corticosteroids (aHR 1.53, 95%CI (1.42-1.66)), followed by selective serotonin or serotonin and norepinephrine reuptake inhibitors (SSRI/SNRI, aHR 1.26, 95%CI (1.17-1.35)), low-dose aspirin (aHR 1.14, 95%CI (1.08-1.20)) and non-steroidal anti-inflammatory drugs (NSAID, aHR 1.10, 95%CI (1.01-1.21)). Significantly higher intracranial bleeding risks in NOAC users were observed with SSRI/SNRIs (aHR 1.50, 95%CI (1.25-1.81)) and corticosteroids (aHR 1.49, 95%CI (1.21-1.84)).

CONCLUSION

Concomitant use of PD interacting drugs, especially P2Y12 inhibitors and corticosteroids, was associated with higher major, gastrointestinal, urogenital, and other bleeding risks in NOAC-treated AF patients. Remarkably, higher intracranial bleeding risks were observed with SSRI/SNRIs and corticosteroids.

National Trends, Risk Factors, and Outcomes of Acute In-Hospital Stroke Following Lung Transplantation in the United States: Analysis of the United Network for Organ Sharing Registry

BACKGROUND

Lung transplantation (LTx) is the definitive treatment for end-stage lung failure. However, there have been no large, long-term studies on the impact of acute in-hospital stroke in this population.

RESEARCH QUESTION

What are the trends, risk factors, and outcomes of acute stroke in patients undergoing LTx in the United States?

STUDY DESIGN AND METHODS

We identified adult first-time isolated LTx recipients from the United Network for Organ Sharing database, which comprehensively captures every transplant in the United States, between May 2005 and December 2020. Stroke was defined as occurring at any time after LTx but prior to discharge. Multivariable logistic regression with stepwise feature elimination was used to identify risk factors for stroke. Freedom from death in patients with a stroke vs those without a stroke was evaluated with Kaplan-Meier analysis. Cox proportional hazards analysis was used to identify predictors of death at 24 months.

RESULTS

Of 28,564 patients (median age, 60 years; 60% male), 653 (2.3%) experienced an acute in-hospital stroke after LTx. Median follow-up was 1.2 (stroke) and 3.0 (non-stroke) years. Annual incidence of stroke increased (1.5% in 2005 to 2.4% in 2020; P for trend = .007), as did lung allocation score and utilization of post-LTx extracorporeal membrane oxygenation (P = .01 and P < .001, respectively). Compared with those without stroke, patients with stroke had lower survival at 1 month (84% vs 98%), 12 months (61% vs 88%), and 24 months (52% vs 80%) (log-rank test, P < .001 for all). In Cox analysis, acute stroke conferred a high hazard of mortality (hazard ratio, 3.01; 95% CI, 2.67-3.41). Post-LTx extracorporeal membrane oxygenation was the strongest risk factor for stroke (adjusted OR, 2.98; 95% CI, 2.19-4.06).

INTERPRETATION

Acute in-hospital stroke post-LTx has been increasing over time and is associated with markedly worse short- and long-term survival. As increasingly sicker patients undergo LTx as well as experience stroke, further research on stroke characteristics, prevention, and management strategies is warranted.

Risk Profiles of New Users of Oral Anticoagulants Between 2011 and 2019 in Germany

Purpose

Over the last decade, the use of direct oral anticoagulants (DOACs) has strongly increased. We aimed to describe and compare risk profiles including potential changes over time among persons with non-valvular atrial fibrillation initiating treatment with different DOACs or phenprocoumon (vitamin K antagonist) between 2011 and 2019 in Germany.

Patients and Methods

Using the German Pharmacoepidemiological Research Database (GePaRD; claims data of ~20% of the German population), we identified persons with a first dispensing of phenprocoumon or a DOAC and a diagnosis of non-valvular atrial fibrillation between August 2011 and December 2019. We described the morbidity of included patients prior to treatment initiation, stratified by year of treatment initiation.

Results

Overall, we included 448,028 new users (phenprocoumon: N = 118,117, rivaroxaban: N = 130,997, apixaban: N = 130,300, edoxaban: N = 38,128, dabigatran: N = 30,486). Comparing new DOAC users in 2019, the proportion with prior ischemic stroke was highest for dabigatran (17%) and lowest for rivaroxaban (8%). The proportion with prior major bleeding was also highest for dabigatran (25%) and lowest for edoxaban (20%). New users of apixaban were oldest and, eg, showed the highest prevalence of congestive heart failure. Changes over time were most pronounced for phenprocoumon. For example, among persons initiating phenprocoumon in 2012 vs 2019, the proportion with prior major bleeding increased from 18% to 35%; the proportion with renal disease increased from 20% to 36% and the proportion with liver disease from 18% to 24%.

Conclusion

This study demonstrated differences in risk profiles between new users of different oral anticoagulants and substantial changes over time among new phenprocoumon users. These differences have to be considered in head-to-head comparisons of these drugs based on observational data, especially regarding potential unmeasured confounding.

Impact of venous thromboembolism on incidence of arterial thromboembolism - An analysis of German outpatient claims data

BACKGROUND

Venous thromboembolism (VTE) and arterial thromboembolism (ATE) are considered as two separate disease-entities. In recent years, studies have reported clear associations between VTE and atherosclerosis. We aimed to evaluate the long-term risk of ATE in VTE patients in comparison to controls without VTE.

METHODS

Nationwide outpatient claims data of all inhabitants with statutory health insurance in Germany were used for secondary data analysis between the years 2011 and 2020. Patients treated in 2013 were stratified by VTE event, and groups were 1:2-matched by age and sex. The hazard for an ATE event in a 5-year follow-up period between patients with and without VTE was calculated with multivariable Cox regression adjusted for age, sex, cardiovascular risk factors, and comorbidities.

RESULTS

Of 69,699,277 individuals treated in the year 2013 by German physicians in outpatient care, in total 686,382 individuals (age 59.8 ± 17.5 years, 65.4 % females) were included comprising 228,794 patients with VTE and 457,588 controls without VTE. VTE patients more often had cardiovascular risk factors (81.6 % vs. 62.2 %) and traditional VTE risk factors. The occurrence of ATE events during follow-up was 1.8 %-points higher in VTE patients in comparison to the controls (9.7 % vs. 7.9 %). VTE events were independently associated with increased occurrence of ATE events within follow-up (HR_adjusted 1.19 [99%CI 1.16-1.23], p < 0.0001).

CONCLUSIONS

Patients with a VTE event have an increased long-term risk for subsequent arterial cardiovascular events. Large prospective cohorts are needed to identify patient subgroups with a very high ATE risk after VTE.

Drug-drug interactions with direct oral anticoagulants for the prevention of ischemic stroke and embolism in atrial fibrillation: a narrative review of adverse events

INTRODUCTION

In randomized trials, direct oral anticoagulants (DOAC) were non-inferior to the vitamin-K-antagonist (VKA) warfarin in preventing stroke/embolism in patients with atrial fibrillation (AF). DOAC are substrates for P-glycoprotein (P-gp), CYP3A4 and CYP2C9. The activity of these enzymes is modulated by several drugs which might induce pharmacokinetic drug-drug interactions (DDI). Drugs affecting platelet function have the potential for pharmacodynamic DDI of DOAC.

AREAS COVERED

The literature was searched for: 'dabigatran,' 'rivaroxaban,' 'edoxaban,' or 'apixaban' and drugs affecting platelet function, CYP3A4-, CYP2C9- or P-gp-activity. Reports about bleeding and embolic events attributed to DDI with DOAC in AF-patients were found for 43 of 171 drugs with interacting potential (25%), most frequently with antiplatelet and nonsteroidal anti-inflammatory drugs. Whereas a co-medication of platelet-affecting drugs is invariably reported to increase the bleeding risk, the findings regarding P-gp-, CYP3A4- and CYP2C9- activity-affecting drugs are ambiguous.

EXPERT OPINION

Tests for plasma DOAC-levels and information about DDI of DOAC should be widely available and user-friendly. If advantages and disadvantages of DOAC and VKA can be investigated exhaustively, individualized anticoagulant therapy can be offered to patients, considering co-medication, comorbidities, genetic and geographic factors and the health care system.

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.

Time Trends in Patient Characteristics of New Rivaroxaban Users with Atrial Fibrillation in Germany and the Netherlands

BACKGROUND

Use of the direct oral anticoagulant rivaroxaban has strongly increased in Europe since its market approval for non-valvular atrial fibrillation in 2011. Patients characteristics of rivaroxaban initiators may have changed over time but this has not been investigated so far.

OBJECTIVE

We aimed to describe time trends of patient baseline characteristics among new rivaroxaban users with non-valvular atrial fibrillation from 2011 to 2016/17 in two European countries.

METHODS

We used data from Germany (German Pharmacoepidemiological Research Database) and the Netherlands (PHARMO Database Network). We included new rivaroxaban users with (i) a first dispensing between 2011 and 2016/17, (ii) ≥ 2 years of age, and (iii) a diagnosis of non-valvular atrial fibrillation and described their baseline medication and comorbidity prior to starting rivaroxaban stratified by year of inclusion.

RESULTS

Overall, 130,652 new rivaroxaban users were included during the study period (Germany: N = 127,743, the Netherlands: N = 2909). The sex ratio and median age remained relatively stable over time. The proportion of patients without prior use of oral anticoagulants before initiation of rivaroxaban increased in both countries between 2011 and 2016/17 (Germany: from 51 to 76%, the Netherlands: from 57 to 85%). In Germany, we observed a relative decrease by 27% in the proportion of new rivaroxaban users with a history of ischemic stroke and by 18% in the proportion with a transient ischemic attack at baseline. No such a pattern was observed in the Netherlands. The proportion of patients with heart failure at baseline showed a three-fold increase in the Netherlands, while there was a relative decrease by 12% in Germany.

CONCLUSIONS

Patient characteristics of new rivaroxaban users with non-valvular atrial fibrillation changed between 2011 and 2016/17, but changes differed between countries. These patterns have methodological implications. They have to be considered in the interpretation of observational studies comparing effectiveness and safety of oral anticoagulants, especially regarding potential bias due to unmeasured confounding.

Vitamin-K-antagonist phenprocoumon versus direct oral anticoagulants in patients with atrial fibrillation: a real-world analysis of German claims data

OBJECTIVES

Direct oral anticoagulants (DOACs) were introduced based on randomised controlled trials (RCTs) comparing them to vitamin-K-antagonist (VKA) warfarin. In Germany, almost exclusively phenprocoumon is used as VKA. RCTs with phenprocoumon being absent we analysed the benefits and harms of DOACs and phenprocoumon for patients with atrial fibrillation (AF) in a real-world setting.

DESIGN

In a retrospective observational cohort study, claims data covering inpatient and outpatient care from 2015 to 2019 were analysed by Cox regression and propensity score matching (PSM).

SETTING

Data from a group of small-sized to medium-sized health insurance companies in Germany.

PARTICIPANTS

We analysed datasets of 71 961 patients with AF and first prescription of phenprocoumon (n=20 179) or DOAC in standard dose (n=51 782). Patients with reduced dose of DOACs were excluded (n=21 724).

OUTCOME MEASURES

Outcomes were thromboembolic events, major bleeding and death during a 12-month follow-up period.

RESULTS

The regression analysis widely showed similarity between phenprocoumon and standard dose DOACs regarding effectiveness and safety. There were only three statistically significant differences: a lower bleeding risk with composite DOACs and apixaban (HR (95% CI) = 0.67 (0.59 to 0.76) and 0.54 (0.46 to 0.63), respectively) and a higher risk of death with rivaroxaban (1.21 (1.10 to 2.34)). The analysis after PSM was consistent with the first two results regarding composite DOACs and apixaban (number needed to treat, NNT 101 and 78) and showed a lower bleeding risk with rivaroxaban (NNT 156). Absolute differences were small.

CONCLUSIONS

The small superiority or non-inferiority of DOACs over warfarin seen in the RCTs might not translate into relevant advantages of DOACs over phenprocoumon. To confirm the hypothesis, an RCT with phenprocoumon is needed. Next to the safety and effectiveness assessments other factors might also play a substantial role in the decision on the right OAC for stroke prevention.

[Prescribing behavior of Bavarian general practitioners at the inpatient-outpatient interface within the context of the Bavarian active substance agreement-qualitative results of the WirtMed Study]

Hintergrund und Ziel

Zur transparenten Steuerung der Arzneimittelausgaben im Rahmen des Wirtschaftlichkeitsgebots (§ 12 Fünftes Buch Sozialgesetzbuch (SGB V)) hat die Kassenärztliche Vereinigung Bayerns im Jahr 2014 die Wirkstoffvereinbarung (WSV) eingeführt. Diese hat die Richtgrößensystematik abgelöst. Mit Bezug auf die Rolle der WSV werden im Artikel die Gründe der Hausärzt*innen (HÄ) für oder gegen eine Weiterverordnung von Arzneimitteln aus dem Krankenhaus beschrieben.

Material und Methode

In einem qualitativen Studiendesign wurden im Zeitraum 11/2019 bis 03/2020 mit bayerischen HÄ Einzelinterviews (n = 18) und 2 Fokusgruppen (n = 10) durchgeführt und nach der qualitativen Inhaltsanalyse ausgewertet.

Ergebnisse

Mit der Einführung der WSV nahmen die Regresssorgen der HÄ insgesamt ab. Große Bedeutung bei Verordnungen haben – vor der Wirtschaftlichkeit – die patient*innenorientierte Versorgung und fachliche Richtigkeit von Therapieentscheidungen. Mit der Entlassmedikation ergeben sich wirtschaftliche Herausforderungen, besonders mit dem Leitsubstanzziel der oralen Antikoagulation, den Generikazielen bei Antidiabetika und bei Therapeutika für das Herz-Kreislauf-System. Allgemein kritisiert werden Rabattverträge, die oft zu Umstellungen von Arzneimitteln führen. Vereinzelt wird von einer „Vormachtstellung“ der Klinikärzt*innen berichtet, die dem hausärztlichen wirtschaftlichen Handeln entgegenstehen. Es fehlt laut HÄ eine sektorenübergreifende Kostenverantwortung.

Diskussion

Ein reibungsloser Schnittstellenübergang ist aus Sicht der HÄ trotz des Rahmenvertrags Entlassmanagement und der neuen Steuerungssystematik der WSV im ambulanten Sektor noch nicht vorhanden. Für eine wirtschaftliche Arzneimittelversorgung bedarf es weiterhin einer sektorenübergreifenden, aber auch bundesländerübergreifenden politischen Diskussion.

Zusatzmaterial online

Im Onlinematerial sind vertiefende Informationen zu der Methodik (Onlinematerial 1: Interview- und Fokusgruppenleitfaden) sowie zur Auswertung (Onlinematerial 2: Kategoriensystem) dieser Studie (10.1007/s00103-022-03563-6) verfügbar.

Clinical outcomes in patients receiving edoxaban or phenprocoumon for prevention of stroke in atrial fibrillation: a German real-world cohort study

Background

Appropriate and timely anticoagulant therapy with vitamin K antagonists (VKAs) or non-vitamin K oral antagonists (NOACs) is essential for stroke prevention in non-valvular atrial fibrillation (NVAF). Comparative data regarding effectiveness and safety for edoxaban vs phenprocoumon, the predominant VKA in Germany, are scarce.

Objectives

The study evaluates effectiveness and safety of edoxaban vs phenprocoumon in NVAF patients in a German real-world setting.

Methods

German statutory health insurance claims data of the Institute for Applied Health Research Berlin (InGef) Research Database from 2014 until 2019 were analyzed. In NVAF patients, new users of edoxaban and phenprocoumon were compared to assess effectiveness (stroke/systemic embolism (SE)) and safety (bleeding) during therapy. Hazard ratios (HR) were estimated through multiple outcome-specific cox proportional hazard models adjusting for baseline characteristics. Outcomes of geriatric patients were analyzed in subgroup analyses.

Results

Between 2015 and 2018, 7,975 and 13,319 NVAF patients newly initiated treatment with edoxaban or phenprocoumon. After adjusting for baseline confounders, the risk of stroke/SE (HR: 0.85, 95% CI: 0.70–1.02) was numerically but not significantly lower, while the risk of major bleeding (HR: 0.69, 95% CI: 0.58–0.81) was significantly lower for edoxaban. In the geriatric subgroups, homogenous results compared to the main analysis were obtained.

Conclusion

The results of this real-world analysis indicated better effectiveness and safety outcomes in patients with NVAF initiating edoxaban treatment compared to phenprocoumon. The findings confirm that the beneficial effects observed in the pivotal ENGAGE AF-TMI 48 trial can also be achieved in real-world use of edoxaban.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00395-x.

Monitoring of direct oral anticoagulants plasma levels for secondary stroke prevention

BACKGROUND

Patients with atrial fibrillation have a relevant risk for ischemic stroke despite the recommended use of direct oral anticoagulants (DOAC). The risk correlates with the functional DOAC plasma levels in clinical trials, but the value of their measurement in community use remains undetermined.

OBJECTIVES

We aim to investigate the clinical implications and the prognostic value of DOAC plasma level measurement during steady state.

METHODS

In this observational clinical cohort study among patients with ischemic stroke and atrial fibrillation, 397 individuals on oral anticoagulants for secondary stroke prevention were included between 2016 and 2020. The functional DOAC plasma levels were measured during steady state. Early stroke recurrence within 3 months was recorded as the main outcome parameter.

RESULTS

Three hundred ninety-seven patients (201 female, mean age 78 [±9] years, median CHA2 DS2 VASc-Score 6 [interquartile range 5-7]) were included. Mean DOAC plasma trough level was 95.9 (±66.9) ng/ml. A high glomerular filtration rate (GFR) was an independent predictor of lower levels in a multivariate model (R coefficient: -0.174, P = .014). During follow-up, 10 patients (3%) suffered from early ischemic stroke recurrence despite the use of DOAC, while 10 clinically relevant bleeding complications occurred (3%). Ischemic stroke recurrence was associated with numerical lower plasma levels for patients on apixaban and dabigatran after propensity score matching.

CONCLUSIONS

Monitoring of DOAC plasma levels could help to identify patients with increased risk for stroke recurrence and should be considered for certain subgroups, including patients with high GFR.

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.

Update on drug interactions with non-vitamin-K-antagonist oral anticoagulants for stroke prevention in elderly patients

Introduction: We update the knowledge, since the last review in 2017, about drug-drug interactions (DDI) of non-vitamin-K-antagonist oral anticoagulants (NOAC) in patients ≥75 years.Areas covered: The literature was searched for: 'dabigatran,' 'rivaroxaban,' 'edoxaban,' or 'apixaban' and drugs, affecting platelet function, CYP3A4-, CYP2C9-, or P-Gp-activity. Pharmacodynamic DDI of NOAC with drugs affecting platelet function like nonsteroidal anti-inflammatory drugs and antiplatelet agents occur most frequently. Pharmacokinetic DDI with NOAC were found for 37 of 117 drugs. Reports about DDI with NOAC were found for 51% of P-gp-affecting, 38% for CYP2C9-affecting and 27% for CYP3A4-affecting drugs. Reports about DDI of cardiovascular drugs with NOAC were the most prevalent, followed by anti-infective and nervous system drugs. NOAC plasma levels were measured in retrospective and cohort studies and were associated with concomitant medication. Reports about DDI of NOAC were found in 71 patients ≥75 years.Expert opinion: The knowledge about DDI of NOAC in elderly patients is very limited. Studies should be carried out to investigate the role of drugs potentially interacting with NOAC, which until now have not been investigated. When studying DDI of NOAC, care should be taken to include elderly patients with impaired renal function and patients on polymedication.

Estimated Thresholds of Minimum Necessary Adherence for Effective Treatment with Direct Oral Anticoagulants - A Retrospective Cohort Study in Health Insurance Claims Data

BACKGROUND

An essential contribution regarding the prevention of thromboembolic events in patients with (non-valvular) atrial fibrillation (AF) is good adherence to direct oral anticoagulants (DOACs). However, it is an open question what "good" adherence means for DOACs or below which threshold non-adherence is clinically relevant for AF patients. Ultimately, such a classification could prevent strokes and associated costs through adjusted treatment regimens or supportive measures.

METHODS

We selected 10,092 AF patients from health insurance claims data between 2014 and 2018 who were issued a majority (at least half of the number) of maximum approved strength prescriptions of one of the following DOACs, namely rivaroxaban, apixaban, or dabigatran. Due to the limited sample size, the prescriptions of dabigatran had to be finally excluded for the cut-off analysis. DOAC adherence was calculated as the proportion of days covered (PDC) by dividing the days of theoretical use (days covered) of the drug by the duration in days of the observation interval. PDC cut-off values were derived from stroke risk as a function of continuous PDC values in time-to-event analyses and corresponding dose-response models. The influence of adherence-promoting interventions (targeted and untargeted) on the occurrence of strokes and related costs was then projected, considering intervention costs per patient.

RESULTS

The population had a mean age of 74.5 years and 50% were female. The median PDC was 0.79 ± 0.28 with a median follow-up time of 1218 days, in which 2% of all DOAC patients had a stroke. The adherence cut-offs for good adherence were identified at 0.78 for rivaroxaban and 0.8 for apixaban. Targeted interventions appeared to be far more cost-effective than untargeted interventions.

CONCLUSION

Clear adherence cut-offs enable healthcare professionals to identify patients with clinically relevant non-adherence. Interventions based on these cut-offs appear to be a promising means to optimize DOAC treatment.