Assessing patient preferences for switching from warfarin to direct oral anticoagulants

Use of Direct Oral Anticoagulation for Isolated Distal Deep Vein Thrombosis in Japanese Orthopedic Patients

Objectives: Although direct oral anticoagulants (DOAC) have become widely used, little is known about the efficacy of DOAC for isolated distal deep vein thrombosis (DVT). Methods: In-hospitalized orthopedic patients with isolated distal DVT who were diagnosed from 2016 to 2018 were enrolled and were followed for 1 year. Embolic events included symptomatic pulmonary embolism (PE) and DVT extension above the knee. Bleeding events were determined in the presence of bleeding academic research consortium (BARC) 2, 3 or 5 bleeding. Results: Of 196 orthopedic patients, 84% of patients (n = 164) received DOAC (DOAC+ group), whereas 16% of patients (n = 32) did not (DOAC- group). Cumulative incidence of embolic events was observed in 1.5% of the DOAC+ group and none of the DOAC- group (p = 0.443). Cumulative incidence of bleeding events was observed in 5.1% of the DOAC+ group and none of the DOAC- group (p = 0.157). The majority of bleeding events (80%) occurred in patients with HAS-BLED scores of 3 or greater. Conclusions: There were no significant differences in embolic events and bleeding events in retrospective data. Balancing thrombotic risk and bleeding risk remains to be key for isolated distal DVT.

Direct-Acting Oral Anticoagulant Dabigatran as a Bridging Therapy while Optimizing Warfarin Dosage for Cardioembolic Stroke

INTRODUCTION

Parenteral heparin is widely used as bridging therapy while optimizing oral anticoagulation (OAC). Newer direct-acting OACs (DOACs) attain therapeutic effect very quickly. We report the use of dabigatran as bridging therapy during warfarin optimization for cardioembolic stroke in two patients who opted to receive warfarin for long-term anticoagulation for secondary stroke prevention.

CASE PRESENTATIONS

Patient A was a 60-year-old man with hypertension, hyperlipidaemia, and gout who was admitted with a sudden onset of left-sided weakness. Clinically, he was alert but had right gaze preference and left-sided hemiplegia. The clinical diagnosis was of a right cortical stroke. He underwent intravenous tPA augmented with sonothrombolysis - the National Institute of Health Stroke Scale (NIHSS) score fell from 7 to 0. Repeat brain scan showed infarcts in the right frontal and parietal lobes. He was found to have atrial fibrillation (AF) and advised anticoagulation. He opted for warfarin with dabigatran bridging which was started on day 2 of his hospital admission. His International Normalized Ratio (INR) exceeded 2 by day 6 of anticoagulation, at which time the bridging dabigatran was stopped, fixed-dose warfarin was continued, and he was discharged well. On subsequent reviews in the clinic, his INR was in the therapeutic range of 2.0-3.0. He had no bleeding or recurrent ischaemic events during follow-up. Patient B was a 78-year-old man with a hypertension, hyperlipidaemia, and diabetes mellitus. He was admitted after he developed difficulty talking and mild right-sided weakness. Clinically, he was alert but had expressive aphasia and mild right-sided upper limb weakness (NIHSS 6). The clinical diagnosis was of a left cortical stroke. The brain scan showed a left posterior frontal and parietal infarct. He was out of the time window for recanalization therapy and was treated conservatively. He was found to have AF and advised anticoagulation. He opted for warfarin with dabigatran bridging which was started on day 1 of his hospital admission. His INR was almost 2 by day 5 of anticoagulation, at which time the bridging dabigatran was stopped and fixed-dose warfarin continued. He declined daily blood taking - his INR 4 days later was in the therapeutic range of 2.0-3.0. He had no bleeding or recurrent ischaemic events. He underwent rehabilitation uneventfully and was discharged well.

CONCLUSIONS

The use of DOACs such as dabigatran as bridging therapy during optimization of OAC is feasible. Compared to heparin as bridging therapy, DOAC has the advantage of oral administration, lower cost, and possibly lower bleeding risks. This novel practice may be applicable in thrombosis in arterial and venous circulations, e.g., ischaemic stroke, deep venous thrombosis, pulmonary embolism.

Participant Engagement and Preference Study for Clinical Outcomes Associated With Atrial Fibrillation: The PEARL-AF Study

Background

Quantifying patients' preferences for health outcomes associated with atrial fibrillation (AF) and its treatments offers a replicable approach to considering the patient perspective in regulatory decision-making.

Objective

The authors conducted a preference survey to estimate the relative importance of AF-related events for use in clinical trial analyses to estimate net health benefits with anticoagulants.

Methods

The survey included nontechnical descriptions of three severities of stroke, systemic embolism, myocardial infarction (MI) with or without subsequent heart failure (HF), major bleeding, clinically relevant nonmajor bleeding, and death. A best-worst scaling question format was used in which patients were shown 10 sets of four events and asked to select what they considered to be most and least serious.

Results

One thousand twenty-eight patients, mean age 69.2 years, 40.4% female, completed the survey. Best-worst scaling importance weights were significantly different across all events except between major bleeding and MI with HF. Death was considered the most serious (reweighted to 1), followed by severe disabling stroke (0.83), then major bleeding (0.53) or MI with HF (0.50), moderate-severity stroke (0.28) and systemic embolism (0.13). Clinically relevant nonmajor bleeding, MI without HF, and minor stroke (0.10, 0.06, and 0.04, respectively) were considered least serious. Events ordered by importance were consistent across age, sex, and race, but relative weights across events varied by sex and race.

Conclusions

Patients expressed relatively high levels of concern about major bleeding compared to moderate-severity stroke or systemic embolism, endpoints frequently used in AF trials. Estimated weights could be used in patient-centered net-benefit determinations for AF therapies.

Thin film microextraction of apixaban from plasma based on the covalent organic framework coated on a mesh prior to liquid chromatography-tandem mass spectrometry

In this research, a new covalent organic framework was synthesized and utilized as a coating in thin film microextraction for the extraction of apixaban from plasma samples. This coating was applied to the mesh modified through immersion in a HF solution. The extracted drug was then analyzed using liquid chromatography-tandem mass spectrometry. By combining the high specific surface area and selectivity of the covalent organic framework, along with integrating the innovative thin film microextraction method and a sensitive analysis system, an efficient analytical approach was achieved. The target analyte was preconcentrated and extracted by immersing of the covalent organic framework-coated mesh as an absorbent into the biological sample. Subsequently, a sonication process was conducted for a specific duration. Following this, the extracted analyte was desorbed using acetonitrile as the elution solvent. The effective parameters of the proposed technique were optimized by using "one-parameter-at-a-time" strategy and the optimal conditions were selected. By integrating the developed method notable achievements were made in the terms of low limits of detection and quantification (0.17 and 0.56 µg/L, respectively), a wide linear range (0.05-250 µg/L), intra- and inter day precisions (with relative standard deviations of ≤14 %), as well as satisfactory extraction recoveries (53 % and 54 % in plasma and deionized water, respectively). Hence, it can be concluded that the introduced technique exhibits high efficiency and reliability when applied to biological samples.

Role of Lifestyle in Thoracic Outlet Syndrome: A Narrative Review

INTRODUCTION

The presence of a positional compression of the neurovascular bundle in the outlet between the thorax and the upper limb during arm movements (mainly abduction) is common but remains asymptomatic in most adults. Nevertheless, a certain number of subjects with thoracic outlet positional compression will develop incapacitating symptoms or clinical complications as a result of this condition. Symptomatic forms of positional neurovascular bundle compression are referred to as "thoracic outlet syndrome" (TOS).

MATERIALS AND METHODS

This paper aims to review the literature and discuss the interactions between aspects of patients' lifestyles in TOS. The manuscript will be organized to report (1) the historical importance of lifestyle evolution on TOS; (2) the evaluation of lifestyle in the clinical routine of TOS-suspected patients, with a description of both the methods for lifestyle evaluation in the clinical routine and the role of lifestyle in the occurrence and characteristics of TOS; and (3) the influence of lifestyle on the treatment options of TOS, with a description of both the treatment of TOS through lifestyle changes and the influence of lifestyle on the invasive treatment options of TOS.

RESULTS

We report that in patients with TOS, lifestyle (1) is closely related to anatomical changes with human evolution; (2) is poorly evaluated by questionnaires and is one of the factors that may induce symptoms; (3) influences the sex ratio in symptomatic athletes and likely explains why so many people with positional compression remain asymptomatic; and (4) can sometimes be modified to improve symptoms and potentially alter the range of interventional treatment options available.

CONCLUSIONS

Detailed descriptions of the lifestyles of patients with suspected TOS should be carefully analysed and reported.

Frequency and clinical outcomes of pharmacist-driven switching from warfarin to direct oral anticoagulants in an underserved patient population: A retrospective cohort study

PURPOSE

Direct oral anticoagulant (DOAC) medications have improved safety, efficacy, and laboratory monitoring requirements compared to warfarin. However, available data are limited on the frequency and clinical outcomes of pharmacist-driven warfarin-to-DOAC switches. We aimed to quantify the frequencies and rationale of warfarin-to-DOAC switches in an underserved population. We also assessed clinical outcomes and compliance with recommended laboratory monitoring after switches.

METHODS

This retrospective cohort study included adult (age 18 years or older) patients on warfarin who were assessed by a clinical pharmacist for switch appropriateness to a DOAC. Study data were collected via manual chart review and included demographics, comorbid illnesses, switch status, the rationale for or against switching, incidence of thromboses and bleeds within 6 months of the switch assessment, and the time to the first complete blood count and renal and hepatic function tests after the switch. Statistical analysis utilized descriptive statistics, including the mean and SD, median and interquartile range, and frequencies and percentages.

RESULTS

Among 189 eligible patients, 108 (57%) were switched from warfarin to a DOAC. The primary rationales for switching were less monitoring (64%) and labile international normalized ratio (32%). The main reason against switching was DOAC inappropriateness (53%), such as in morbid obesity (14%). Patient preference was commonly cited in both groups (54% and 36%, respectively). The overall incidence of thrombotic events (9%) and bleeds (15%) after switch assessment was low. Laboratory monitoring after switches was consistent with current recommendations.

CONCLUSION

No increase in harm was observed 6 months after switch assessment when pharmacists at a family medicine clinic switched underserved patients from warfarin to DOACs.

Clinical outcomes of oral anticoagulant discontinuation in atrial fibrillation: a systematic review and meta-analysis

INTRODUCTION

Oral anticoagulants (OACs) should generally be continued lifelong in patients with atrial fibrillation (AF) to ensure optimal benefits, unless contraindications arise. However, discontinuation of OACs might occur for various reasons, potentially affecting clinical outcomes. In this review, we synthesized evidence on the clinical outcomes following OAC discontinuation in patients with AF.

METHODS

We conducted a systematic review and meta-analysis using PubMed, Embase and Scopus. Cohort or case-control studies were included if data were available on clinical outcomes of OAC discontinuation, compared with continuation, in patients with AF. A random-effect meta-analyses were conducted for key outcomes of stroke, mortality, and major bleeding.

RESULTS

Eighteen observational studies having a total of 283,418 patients were included. Discontinuation significantly increased the risk of stroke (hazard ratio [HR] 1.88; 95% confidence interval [CI] 1.58-2.23), all-cause (HR 1.90; 95% CI 1.40-2.59) and cardiovascular (HR 1.83; 95% CI 1.06-3.18) mortality. The risk of major bleeding was not significantly different between the discontinued and continued groups (HR 1.04; 95% CI 0.72-1.52).

CONCLUSIONS

Discontinuation of OAC therapy was associated with an increased risk of stroke and mortality, with no difference in the risk of major bleeding. Acknowledging heterogeneity among the studies, the findings underline the need to ensure continuity of OAC therapy in patients with AF to prevent thrombotic complications and associated mortality.

PROSPERO REGISTRATION NUMBER

CRD42020186116.

Oral anticoagulant switching in patients with atrial fibrillation: a scoping review

INTRODUCTION

Oral anticoagulants (OACs) prevent stroke in patients with atrial fibrillation (AF). Several factors may cause OAC switching.

OBJECTIVES

To examine the phenomenon of OAC switching in patients with AF, including all available evidence; frequency and patterns of switch, clinical outcomes, adherence, patient-reported outcomes, reasons for switch, factors associated with switch and evidence gaps.

DESIGN

Scoping review.

DATA SOURCES

MEDLINE, Embase and Web of Science, up to January 2022.

RESULTS

Of the 116 included studies, 2/3 examined vitamin K antagonist (VKA) to direct-acting OAC (DOAC) switching. Overall, OAC switching was common and the definition of an OAC switch varied across. Switching from VKA to dabigatran was the most prevalent switch type, but VKA to apixaban has increased in recent years. Patients on DOAC switched more to warfarin than to other DOACs. OAC doses involved in the switches were hardly reported and patients were often censored after the first switch. Switching back to a previously taken OAC (frequently warfarin) occurred in 5%-21% of switchers.The risk of ischaemic stroke and gastrointestinal bleeding in VKA to DOAC switchers compared with non-switchers was conflicting, while there was no difference in the risk of other types of bleeding. The risk of ischaemic stroke in switchers from DOAC versus non-switchers was conflicting. Studies evaluating adherence found no significant changes in adherence after switching from VKA to DOAC, however, an increase in satisfaction with therapy were reported. Reasons for OAC switch, and factors associated with OAC switch were mostly risk factors for stroke and bleeding. Clinical outcomes, adherence and patient-reported outcomes were sparse for switches from DOACs.

CONCLUSIONS

OAC switching is common in patients with AF and patients often switch back to an OAC they have previously been on. There are aspects of OAC switching that have received little study, especially in switches from DOACs.

Risk of post-extraction bleeding with direct oral anticoagulant compared with warfarin: Retrospective cohort study using large scale claims data in Japan

INTRODUCTION

Comparative safety of direct oral anticoagulants vs. warfarin in patients undergoing tooth extraction remains unclear. We compared the incidence of post-extraction bleeding between patients taking warfarin and those taking direct oral anticoagulants (DOACs) using administrative claims data.

MATERIALS AND METHODS

We identified outpatients on anticoagulant therapy who underwent permanent tooth extraction between 2015 and 2020 and categorized them into the warfarin and DOAC groups based on medication prescribed within six months prior to tooth extraction. We used the overlap propensity score weighting method to balance the baseline characteristics between the groups and compared the incidence of post-extraction bleeding within seven days after tooth extraction.

RESULTS

Among 5253 eligible patients, those in the DOAC group (n = 3696) were older and less frequently prescribed antiplatelets than those in the warfarin group (n = 1557). The distribution of tooth extraction type and number of teeth extracted in a single procedure did not differ between the groups. The unadjusted incidences of post-extraction bleeding in the warfarin and DOAC groups were 35 (2.2 %) and 71 (1.9 %), respectively. Moreover, the overlap weighting analysis showed that the adjusted odds ratio of post-extraction bleeding in the DOAC group in comparison with that in the warfarin group was 0.84 (95 % confidence interval, 0.54-1.31).

CONCLUSION

The incidence of post-extraction bleeding in patients taking DOACs was comparable to that in patients taking warfarin. The findings suggest that dentists and physicians should exercise the same degree of caution when extracting teeth in patients on DOACs and those on warfarin in terms of post-extraction bleeding.

Antithrombin Therapy: Current State and Future Outlook

Antithrombin (AT) is a natural anticoagulant pivotal in inactivating serine protease enzymes in the coagulation cascade, making it a potent inhibitor of blood clot formation. AT also possesses anti-inflammatory properties by influencing anticoagulation and directly interacting with endothelial cells. Hereditary AT deficiency is one of the most severe inherited thrombophilias, with up to 85% lifetime risk of venous thromboembolism. Acquired AT deficiency arises during heparin therapy or states of hypercoagulability like sepsis and premature infancy. Optimization of AT levels in individuals with AT deficiency is an important treatment consideration, particularly during high-risk situations such as surgery, trauma, pregnancy, and postpartum. Here, we integrate the existing evidence surrounding the approved uses of AT therapy, as well as potential additional patient populations where AT therapy has been considered by the medical community, including any available consensus statements and guidelines. We also describe current knowledge regarding cost-effectiveness of AT concentrate in different contexts. Future work should seek to identify specific patient populations for whom targeted AT therapy is likely to provide the strongest clinical benefit.

Effectiveness and Safety of Extended Oral Anticoagulant Therapy in Patients with Venous Thromboembolism: A Retrospective Cohort Study

Limited real-world evidence exists for effectiveness and safety of extended oral anticoagulation beyond 6 months of initial treatment in prevention of recurrent venous thromboembolism (VTE) and adverse major bleeding events among patients with VTE. Using MarketScan Commercial and Medicare Supplemental databases (2013-2019), we conducted a retrospective cohort study to compare the risk of recurrent VTE and major bleeding events during extended treatment among patients with VTE who completed the 6-month initial treatment and received extended oral anticoagulant treatment with apixaban, warfarin, or no extended treatment. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox proportional hazards modeling with inverse probability treatment weighting. We identified 14,818 patients with extended treatment of apixaban (n = 4,338), warfarin (n = 5,298), or no extended treatment (n = 5,182). Compared with no extended treatment, apixaban use was associated with decreased risk of recurrent VTE (HR: 0.10, 95% CI: 0.04-0.26) without increased risk of major bleeding events (HR: 1.06, 95% CI: 0.52-2.17); warfarin use was associated with decreased risk of recurrent VTE (HR: 0.23, 95% CI: 0.12-0.44) but with increased risk of major bleeding events (HR: 2.64, 95% CI: 1.51-4.59). Compared with warfarin, apixaban use was associated with decreased risk of major bleeding events (HR: 0.42, 95% CI: 0.22-0.80) but no difference in risk of recurrent VTE (HR: 0.46, 95% CI: 0.15-1.36). In a real-world clinical setting, extended anticoagulation with apixaban or warfarin was associated with decreased risk of recurrent VTE compared with no extended treatment, and apixaban had a better safety profile with fewer major bleeding events compared with warfarin among commercially insured patients with VTE.

Veterans Perceptions of Satisfaction and Convenience with Anticoagulants for Atrial Fibrillation: Warfarin versus Direct Oral Anticoagulants

BACKGROUND

Atrial fibrillation (AFib) is associated with high morbidity and mortality. Traditionally, AFib was treated with warfarin, yet recent evidence suggests patients may favor direct oral anticoagulants (DOACs). Variation in preferences is common and we explored patients' perceptions of satisfaction and convenience of DOACs versus warfarin within the Veterans Health Administration (VA).

PATIENTS AND METHODS

We administered a cross-sectional survey, the Perception of Anticoagulant Treatment Questionnaire 2 (PACT-Q2), to Veterans residing in New England, age ≥65, diagnosed with AFib, and actively taking anticoagulant medication in fiscal year 2018. Survey recipients were randomly selected among patients on warfarin (n=200) or DOACs (n=200). A selection of survey respondents agreed to a follow-up semi-structured interview (n=16) to further investigate perceptions of satisfaction and convenience.

RESULTS

Of 400 patients, 187 completed the PACT-Q2 survey (49% on DOACs; 51% on warfarin). DOACs received significantly higher convenience ratings than warfarin (87.6, SD 13.5 vs 81.1, SD 18.8; p=0.007); there was no difference in satisfaction (64.2, SD 20.5 SD, warfarin vs, 67.3, SD 19.4, DOACs). Interview results showed that participants perceived their treatment to be convenient. However, participants expressed challenges related to the convenience of taking warfarin or DOACs, such as warfarin users having to follow dietary recommendations or DOAC users desiring some additional monitoring to answer questions or concerns. Overall, warfarin and DOAC users reported satisfaction with ongoing monitoring methods, although a few DOAC users expressed uncertainties with the frequency of monitoring. For most participants, concerns about side effects did not differ by anticoagulant type nor affect satisfaction.

CONCLUSION

Our survey and interview results showed variable patient satisfaction and perceptions of convenience with both DOACs and warfarin. Although DOACs are increasingly prescribed for AFib, some Veterans felt that regular follow-up on warfarin was advantageous. Our findings demonstrate the importance of patient-centered decision-making in AFib treatment in the VA patient population.