A tailored treatment strategy: a modern approach for stroke prevention in patients with atrial fibrillation

Oral anticoagulant treatment in atrial fibrillation: the AFIRMA real-world study using natural language processing and machine learning

INTRODUCTION

Oral anticoagulation (OAC) is key in atrial fibrillation (AF) thromboprophylaxis, but Spain lacks substantial real-world evidence. We aimed to analyze the prevalence, clinical characteristics, and treatment patterns among patients with AF undertaking OAC, using natural language processing (NLP) and machine learning (ML).

MATERIALS AND METHODS

This retrospective study included AF patients on OAC from 15 Spanish hospitals (2014-2020). Using EHRead® (including NLP and ML), and SNOMED_CT, we extracted and analyzed patient demographics, comorbidities, and OAC treatment from electronic health records. AF prevalence was estimated, and a descriptive analysis was conducted.

RESULTS

Among 4,664,224 patients in our cohort, AF prevalence ranged from 1.9% to 2.9%. A total of 57,190 patients on OAC therapy were included, 80.7% receiving Vitamin K antagonists (VKA) and 19.3% Direct-acting OAC (DOAC). The median age was 78 and 76 years respectively, with males constituting 53% of the cohort. Comorbidities like hypertension (76.3%), diabetes (48.0%), heart failure (42.2%), and renal disease (18.7%) were common, and more frequent in VKA users. Over 50% had a high CHA2DS2-VASc score. The most frequent treatment switch was from DOAC to acenocoumarol (58.6% to 70.2%). In switches from VKA to DOAC, apixaban was the most chosen (35.2%).

CONCLUSIONS

Utilizing NLP and ML to extract RWD, we established the most comprehensive Spanish cohort of AF patients with OAC to date. Analysis revealed a high AF prevalence, patient complexity, and a marked VKA preference over DOAC. Importantly, in VKA to DOAC transitions, apixaban was the favored option.

Influence of the COVID-19 pandemic on patients receiving oral anticoagulants for the treatment of non-valvular atrial fibrillation

Background

Frequent monitoring of patients declined during the COVID-19 pandemic, harming patients with chronic diseases who critically needed correct monitoring. We evaluated the impact of the COVID-19 pandemic in patients with non-valvular atrial fibrillation (NVAF) receiving treatment with vitamin K antagonists (VKA) or non-vitamin K antagonist oral anticoagulants (NOAC) in clinical practice in Spain.

Methods

This observational, retrospective study analyzed prevalent patients treated with NOAC/VKA on 14/03/2019 (pre-COVID-19 period) and 14/03/2020 (COVID-19 period), who were followed up to 12 months. The study also considered incident patients who started treatment with NOAC/VKA between 15/03/2019 and 13/03/2020 (pre-COVID-19 period) and from 15/03/2020 to 13/03/2021 (COVID-19 period). Demographic characteristics, comorbidities, effectiveness, treatment patterns, and healthcare resource utilization were considered.

Results

Prevalent patients amounted to 12,336 and 13,342 patients, whereas 1,612 and 1,602 incident patients were included in the pre-COVID-19 and COVID-19 periods, respectively. Prevalent patients treated with VKA had more strokes, thromboembolism, and major bleeding compared to those receiving NOAC, particularly during the COVID-19 period. NOAC patients had a 12 % lower risk of death than those on treatment with VKA (Hazard ratio = 0.88 [95 % CI: 0.81 - 0.95], p = 0.033). In addition, VKA patients were less persistent after 12 months than NOAC patients (pre-COVID-19 period: 52.1 % vs. 78.9 %, p < 0.001; COVID-19 period: 49.2 % vs. 80.3 %, p < 0.001), and required more healthcare visits and hospitalizations than those on treatment with NOAC.

Conclusion

Compared to VKA, NOAC seems to have reduced the incidence of severe events and the use of healthcare resources for NVAF, particularly during the pandemic.

Healthcare resources and costs associated with nonvalvular atrial fibrillation in Spain: apixaban versus acenocoumarol

Aim: Healthcare resources usage and costs associated to nonvalvular atrial fibrillation (NVAF) were analyzed in Spain. Methods: This is an observational and retrospective study on patients with NVAF who started their treatment with apixaban or acenocoumarol between 1 January 2015 and 31 December 2017. Results: 2160 patients treated with apixaban were paired (1:1) with patients treated with acenocoumarol (propensity score matching). Apixaban reduced the incidence of strokes and systemic embolisms, minor and major bleedings and deaths, versus acenocoumarol. Apixaban led to reductions of 80, 55 and 43% in costs related to nursing visits, hospitalizations, and emergency visits, respectively, leading to annual cost savings of €274/patient, from the perspective of society. Conclusion: Our results suggested that apixaban is a cost-effective alternative for patients with NVAF.

Low Quality of Warfarin Therapy is Associated With Female Gender but Not With Polypharmacy in Patients With Atrial Fibrillation

Background: We examined the impact of polypharmacy on the quality of the anticoagulation therapy in patients with atrial fibrillation. We also examined the factors that affect the stability of warfarin therapy.

Methods and Results: This retrospective study was conducted using data from 157 consecutive outpatients with atrial fibrillation in a single tertiary referral hospital. Patients who were prescribed warfarin continuously and for whom PT-INR was examined at least three times in a year were included in this study. We examined the quality of warfarin therapy using time in the therapeutic INR range (TTR), percentage of PT-INR determinations in range (PINRR), and the coefficient variation (CV) of PT-INR. We found that the number of prescribed medicines was significantly associated with high BMI and low eGFR, but not with TTR, PINRR, and the coefficient variation of PT-INR in patients with atrial fibrillation. We also found that female gender was independently associated with low PINRR in this study population.

Conclusion: Polypharmacy did not deteriorate the quality of warfarin therapy in patients with atrial fibrillation treated in the tertiary referral hospital. Female gender was an independent predictor of the low quality of warfarin therapy.

Combination of Oral Anticoagulants and Single Antiplatelets versus Triple Therapy in Nonvalvular Atrial Fibrillation and Acute Coronary Syndrome: Stroke Prevention among Asians

Atrial fibrillation (AF), the most prevalent arrhythmic disease, tends to foster thrombus formation due to hemodynamic disturbances, leading to severe disabling and even fatal thromboembolic diseases. Meanwhile, patients with AF may also present with acute coronary syndrome (ACS) and coronary artery disease (CAD) requiring stenting, which creates a clinical dilemma considering that majority of such patients will likely receive oral anticoagulants (OACs) for stroke prevention and require additional double antiplatelet treatment (DAPT) to reduce recurrent cardiac events and in-stent thrombosis. In such cases, the gentle balance between bleeding risk and atherothromboembolic events needs to be carefully considered. Studies have shown that congestive heart failure, hypertension, age ≥ 75 years (doubled), diabetes mellitus, and previous stroke or transient ischemic attack (TIA; doubled)-vascular disease, age 65 to 74 years, sex category (female; CHA ₂ DS ₂ -VASc) scores outperform other scoring systems in Asian populations and that the hypertension, abnormal renal/liver function (1 point each), stroke, bleeding history or predisposition, labile international normalized ratio (INR), elderly (>65 years), drugs/alcohol concomitantly (1 point each; HAS-BLED) score, a simple clinical score that predicts bleeding risk in patients with AF, particularly among Asians, performs better than other bleeding scores. A high HAS-BLED score should not be used to rule out OAC treatment but should instead prompt clinicians to address correctable risk factors. Therefore, the current review attempted to analyze available data from patients with nonvalvular AF who underwent stenting for ACS or CAD and elaborate on the direct-acting oral anticoagulant (DOAC) and antiplatelet management among such patients. For majority of the patients, "triple therapy" comprising OAC, aspirin, and clopidogrel should be considered for 1 to 6 months following ACS. However, the optimal duration for "triple therapy" would depend on the patient's ischemic and bleeding risks, with DOACs being obviously safer than vitamin-K antagonists.

Patient characteristics and stroke and bleeding events in nonvalvular atrial fibrillation patients treated with apixaban and vitamin K antagonists: a Spanish real-world study

Aim: To compare the risk of stroke, systemic thromboembolism and bleeding, in patients initiating apixaban or acenocoumarol for the treatment of nonvalvular atrial fibrillation. Methods: An observational, retrospective study was performed using medical records of patients who initiated apixaban or acenocoumarol between 2015 and 2017. Propensity score matching was used to match patients; stroke, systemic thromboembolism, major and minor bleeding events were compared between the matched patients. Results: Patients who were prescribed apixaban had a lower rate of systemic embolism/stroke (hazard ratio [HR] = 0.54; 95% CI: 0.38–0.78; p = 0.001), minor bleeding (HR = 0.64; 95% CI: 0.52–0.79; p < 0.001) and major bleeding (HR = 0.51; 95% CI: 0.37–0.72; p < 0.001). Conclusion: Patients prescribed apixaban for the treatment of nonvalvular atrial fibrillation had lower rates of thromboembolic events and minor/major bleeding than patients on acenocoumarol.

High Detection Rate of Atrial Fibrillation With Insertable Cardiac Monitor Implantation in Patients With Cryptogenic Stroke Diagnosed by Magnetic Resonance Imaging

BACKGROUND

Detection and treatment of atrial fibrillation (AF) is a major goal in preventing secondary stroke. Insertable cardiac monitors (ICMs) are available for diagnosis of arrhythmia monitoring in patients with cryptogenic stroke. Magnetic resonance imaging (MRI)-based diagnostic evaluation for acute ischemic stroke subtype classification is common in Japan and can be useful for specific diagnosis of cryptogenic stroke.

PURPOSE

We aimed to investigate the detection rate of AF with an ICM in patients with cryptogenic stroke who were diagnosed by MRI.

METHODS

We performed a retrospective, multicenter, observational study. AF monitoring data of an ICM (Reveal LINQ) in patients with cryptogenic stroke were registered from 5 stroke centers in Japan between October 2016 and March 2018. ICM candidates in cryptogenic stroke were diagnosed by MRI-based evaluation and selected according to the criteria proposed by the Japan Stroke Society. Detection of AF was defined as AF for longer than 120 seconds.

RESULTS

Eighty-four consecutive patients (64 men; aged 38-90 years) underwent ICM implantation after diagnosis of cryptogenic stroke. AF was detected in 22 of 84 (26.2%) patients with an ICM during a median follow-up of 221.5 days (range: 93-365 days). The detection rate of AF within 3 months after ICM implantation was 21.4%.

CONCLUSIONS

The AF detection rate with an ICM is approximately one fifth within 3 months in patients with cryptogenic stroke as diagnosed by MRI. Our data suggest that the Japanese criteria based on MRI may be useful for selecting adequate candidates for ICM implantation.

Improved Outcomes by Integrated Care of Anticoagulated Patients with Atrial Fibrillation Using the Simple ABC (Atrial Fibrillation Better Care) Pathway

BACKGROUND

Integrated care for the clinical management of atrial fibrillation patients is advocated as a holistic way to improve outcomes; the simple Atrial fibrillation Better Care (ABC) pathway has been proposed. The ABC pathway streamlines care as follows: 'A' Avoid stroke; 'B' Better symptom management; 'C' Cardiovascular and Comorbidity optimization.

METHODS

We performed a post hoc analysis of the Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) trial. An 'integrated care' approach was defined according to the ABC pathway. Patients fulfilling all criteria were categorized as the 'ABC' group; those not fulfilling all criteria were the 'non-ABC' group. Trial-adjudicated all-cause death, composite outcome of stroke/major bleeding/cardiovascular death, and first hospitalization were the main study outcomes.

RESULTS

Among the 4060 patients in the original cohort, 3169 (78%) had available data to compare integrated care (ABC; n = 222; 7%) vs non-ABC (n = 2947; 93%) management. Over a median follow-up of 3.7 (interquartile range, 2.8-4.6) years, atrial fibrillation patients managed with integrated care (ABC group) had lower rates for all study outcomes (all P < .001) compared with the non-ABC group. A Cox multivariable regression analysis showed that atrial fibrillation patients managed in the ABC group had a significantly lower risk of all-cause death (hazard ratio [HR], 0.35; 95% confidence interval [CI], 0.17-0.75), composite outcome (HR, 0.35; 95% CI, 0.18-0.68), and first hospitalization (HR, 0.65; 95% CI, 0.53-0.80).

CONCLUSIONS

The simple ABC pathway allows the streamlining of integrated care for atrial fibrillation patients in a holistic manner and is associated with a lower risk of adverse outcomes (including mortality, stroke/major bleeding/cardiovascular death, and hospitalization).

Emerging therapeutic uses of direct-acting oral anticoagulants: An evidence-based perspective

Direct-acting oral anticoagulants (DOACs) were claimed to cause a potential paradigm shift in the therapeutic scenario of patients requiring short- and long-term anticoagulation, by virtue of their pharmacological properties, perceived as innovative. The evidence gathered so far (from pre-approval pivotal trials to real-world post-marketing observational data) consistently confirmed that DOACs are overall comparable to vitamin-K antagonists (VKAs) in terms of safety, efficacy and effectiveness and unequivocally documented a consistent and clinically relevant reduced risk of intracranial bleeding in the settings of non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE). Interestingly, two parallel paths can be identified in the current research scenario: A) in the aforementioned consolidated therapeutic indications, an innovative approach is directed towards tailored treatment strategies, to identify patients most likely to benefit from one of the different anticoagulant drugs, in particular subpopulations at increased risk of adverse events (e.g., bleeding); B) in unconventional settings, DOACs are gaining interest for potential use in emerging diseases characterized by arterial and venous thromboembolic risk. In these scenarios, the risk-benefit profile of DOACs, as compared to VKAs or heparins, is less defined. The aim of this review is to critically assess the body of evidence underlying emerging therapeutic uses of DOACs (e.g., heparin-induced thrombocytopenia, anti-phospholipid antibody syndrome), including evolving issues in special populations (e.g., patients with VTE and cancer or cirrhosis). This will be achieved by analyzing the strength (i.e., systematic reviews, randomized clinical trials, observational studies, case report/series) and consistency (i.e., concordance) of both published and unpublished evidence registered in major public repositories.