Management of oral anticoagulation after cardioembolic stroke and stroke survival data from a population based stroke registry (LuSSt)

Performance of modeling and balancing approach methods when using weights to estimate treatment effects in observational time-to-event settings

In observational studies weighting techniques are often used to overcome bias due to confounding. Modeling approaches, such as inverse propensity score weighting, are popular, but often rely on the correct specification of a parametric model wherein neither balance nor stability are targeted. More recently, balancing approach methods that directly target covariate imbalances have been proposed, and these allow the researcher to explicitly set the desired balance constraints. In this study, we evaluate the finite sample properties of different modeling and balancing approach methods, when estimating the marginal hazard ratio, through Monte Carlo simulations. The use of the different methods is also illustrated by analyzing data from the Swedish stroke register to estimate the effect of prescribing oral anticoagulants on time to recurrent stroke or death in stroke patients with atrial fibrillation. In simulated scenarios with good overlap and low or no model misspecification the balancing approach methods performed similarly to the modeling approach methods. In scenarios with bad overlap and model misspecification, the modeling approach method incorporating variable selection performed better than the other methods. The results indicate that it is valuable to use methods that target covariate balance when estimating marginal hazard ratios, but this does not in itself guarantee good performance in situations with, e.g., poor overlap, high censoring, or misspecified models/balance constraints.

Oral anticoagulation in patients with atrial fibrillation and acute ischaemic stroke: design and baseline data of the prospective multicentre Berlin Atrial Fibrillation Registry

AIMS

The Berlin Atrial Fibrillation Registry was designed to analyse oral anticoagulation (OAC) prescription in patients with atrial fibrillation (AF) and acute ischaemic stroke.

METHODS AND RESULTS

This investigator-initiated prospective multicentre registry enrolled patients at all 16 stroke units located in Berlin, Germany. The ongoing telephone follow-up is conducted centrally and will cover 5 years per patient. Within 2014 and 2016, 1080 patients gave written informed consent and 1048 patients were available for analysis. Median age was 77 years [interquartile range (IQR) 72-83], 503 (48%) patients were female, and 254 (24%) had a transient ischaemic attack (TIA). Overall, 470 (62%) out of 757 patients with known AF and a (pre-stroke) CHA2DS2-VASc ≥ 1 were anticoagulated at the time of stroke. At hospital discharge, 847 (81.3%) of 1042 patients were anticoagulated. Thereof 710 (68.1%) received a non-vitamin K-dependent oral anticoagulant (NOAC) and 137 (13.1%) a vitamin K antagonist (VKA). Pre-stroke intake of a NOAC [odds ratio (OR) 15.6 (95% confidence interval, 95% CI 1.97-122)] or VKA [OR 0.04 (95% CI 0.02-0.09)], an index TIA [OR 0.56 (95% CI 0.34-0.94)] rather than stroke, heart failure [OR 0.49 (95% CI 0.26-0.93)], and endovascular thrombectomy at hospital admission [OR 12.9 (95% CI 1.59-104)] were associated with NOAC prescription at discharge. Patients' age or AF type had no impact on OAC or NOAC use, respectively.

CONCLUSION

About 60% of all registry patients with known AF received OAC at the time of stroke or TIA. At hospital discharge, more than 80% of AF patients were anticoagulated and about 80% of those were prescribed a NOAC.

The 2020 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Comprehensive Guidelines for the Management of Atrial Fibrillation

The Canadian Cardiovascular Society (CCS) atrial fibrillation (AF) guidelines program was developed to aid clinicians in the management of these complex patients, as well as to provide direction to policy makers and health care systems regarding related issues. The most recent comprehensive CCS AF guidelines update was published in 2010. Since then, periodic updates were published dealing with rapidly changing areas. However, since 2010 a large number of developments had accumulated in a wide range of areas, motivating the committee to complete a thorough guideline review. The 2020 iteration of the CCS AF guidelines represents a comprehensive renewal that integrates, updates, and replaces the past decade of guidelines, recommendations, and practical tips. It is intended to be used by practicing clinicians across all disciplines who care for patients with AF. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system was used to evaluate recommendation strength and the quality of evidence. Areas of focus include: AF classification and definitions, epidemiology, pathophysiology, clinical evaluation, screening and opportunistic AF detection, detection and management of modifiable risk factors, integrated approach to AF management, stroke prevention, arrhythmia management, sex differences, and AF in special populations. Extensive use is made of tables and figures to synthesize important material and present key concepts. This document should be an important aid for knowledge translation and a tool to help improve clinical management of this important and challenging arrhythmia.

Temporal Trends and Predictors of Drug Utilization and Outcomes in First-Ever Stroke Patients: A Population-Based Study Using the Singapore Stroke Registry

INTRODUCTION

Drug utilization and outcomes research in multi-ethnic Asian stroke populations is lacking.

OBJECTIVES

Our objective was to examine temporal trends and predictors of drug utilization and outcomes in a multi-ethnic Asian stroke population.

METHODS

This registry-based study included ischemic and hemorrhagic first-ever stroke patients hospitalized between 2009 and 2016. Utilization of medications included in-hospital thrombolytic agents, early antithrombotics (antiplatelets, anticoagulants) within 48 h of admission, and antithrombotics and statins at discharge. Outcomes analyzed were in-hospital all-cause mortality; 28-day, 90-day, and 1-year case fatality (CF); and discharge destination.

RESULTS

Of the 36,615 included patients, 81.6% had ischemic stroke and 18.4% had hemorrhagic stroke (15.5% intracerebral hemorrhage [ICH] and 2.8% subarachnoid hemorrhage [SAH]). For ischemic stroke, the combined use of all three guideline medications (in-hospital thrombolytic therapy, as well as antithrombotics and statins at discharge) increased (P = 0.006). Being on the stroke pathway was associated with prescription of all three guideline medications in ischemic stroke. Decreasing trends for in-hospital mortality, 28-day, 90-day, and 1-year CF and proportion of patients discharged home without rehabilitation appointment were observed in ischemic stroke (P < 0.05) but not in ICH or SAH (apart from 28-day CF). Ischemic stroke patients who received guideline medications were less likely to die or be discharged to nursing homes and chronic sick hospitals. Hemorrhagic stroke patients prescribed statins at discharge were less likely to have 28-day and 1-year CF.

CONCLUSIONS

Prescription of secondary stroke preventive medications (particularly in ischemic stroke) was associated with more favorable outcomes, highlighting the importance of physician adherence to evidence-based pharmacotherapy.

Timing of anticoagulation therapy in patients with acute ischaemic stroke and atrial fibrillation

In patients with acute stroke and atrial fibrillation (AF), the risk of early recurrence has been reported to range between 0.1% and 1.3% per day. Anticoagulants are the most effective therapy for the prevention of recurrent ischaemic stroke in these patients, but randomised clinical trials have failed to produce any evidence supporting the administration of heparin within 48 hours from stroke onset as it has been associated with a non-significant reduction in the recurrence of ischaemic stroke, no substantial reduction in death and disability, and an increase in intracranial bleeding. As early haemorrhagic transformation is a major concern in the acute phase of stroke patients with AF, determining the optimal time to start anticoagulant therapy is essential. This review which focuses on the epidemiology of recurrent ischaemic stroke and haemorrhagic transformation in patients with acute ischaemic stroke and AF, proposes a model for decision making on optimal timing for initiating anticoagulation, based on currently available evidence.

Personalized Analysis by Validation of Monte Carlo for Application of Pathways in Cardioembolic Stroke

BACKGROUND Cardioembolic stroke (CES), which causes 20% cause of all ischemic strokes, is associated with high mortality. Previous studies suggest that pathways play a critical role in the identification and pathogenesis of diseases. We aimed to develop an integrated approach that is able to construct individual networks of pathway cross-talk to quantify differences between patients with CES and controls. MATERIAL AND METHODS One biological data set E-GEOD-58294 was used, including 23 normal controls and 59 CES samples. We used individualized pathway aberrance score (iPAS) to assess pathway statistics of 589 Ingenuity Pathways Analysis (IPA) pathways. Random Forest (RF) classification was implemented to calculate the AUC of every network. These procedures were tested by Monte Carlo Cross-Validation for 50 bootstraps. RESULTS A total of 28 networks with AUC >0.9 were found between CES and controls. Among them, 3 networks with AUC=1.0 had the best performance for classification in 50 bootstraps. The 3 pathway networks were able to significantly identify CES versus controls, which showed as biomarkers in the regulation and development of CES. CONCLUSIONS This novel approach could identify 3 networks able to accurately classify CES and normal samples in individuals. This integrated application needs to be validated in other diseases.

Minimizing bleeding risk in patients receiving direct oral anticoagulants for stroke prevention

Many primary care physicians are wary about using direct oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation (AF). Factors such as comorbidities, concomitant medications, and alcohol misuse increase concerns over bleeding risk, especially in elderly and frail patients with AF. This article discusses strategies to minimize the risk of major bleeding events in patients with AF who may benefit from oral anticoagulant therapy for stroke prevention. The potential benefits of the DOACs compared with vitamin K antagonists, in terms of a lower risk of intracranial hemorrhage, are discussed, together with the identification of reversible risk factors for bleeding and correct dose selection of the DOACs based on a patient’s characteristics and concomitant medications. Current bleeding management strategies, including the new reversal agents for the DOACs and the prevention of bleeding during preoperative anticoagulation treatment, in addition to health care resource use associated with anticoagulation treatment and bleeding, are also discussed. Implementing a structured approach at an individual patient level will minimize the overall risk of bleeding and should increase physician confidence in using the DOACs for stroke prevention in their patients with nonvalvular AF.