ArticleOpen heart2021
OpenSAFELY: impact of national guidance on switching anticoagulant therapy during COVID-19 pandemic.
Article in Open heart, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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Who cites it
18 citing papers in PubMed, 28 citations in OpenAlex.
- FAIR by design (TRACE): A Trusted Research Access & Collaboration Environment.BMC medical informatics and decision making · 2026Article
- The evolution of anticoagulants for the prevention and treatment of deep vein thrombosis.Anaesthesia and intensive care · 2026Article
- Use of Electronic Patient Record Systems for Rapid Response to an MHRA Public Assessment Report: Retrospective Observational Study.JMIR formative research · 2026Observational
- Trends in Antithrombotic Therapy Initiation Among Patients With Stroke Pre- and Post-COVID-19 in Sweden-An Interrupted Time Series Study.Basic & clinical pharmacology & toxicology · 2026Article
- Optimisation of oral anticoagulation for stroke prevention: a scoping review of factors influencing implementation.BMJ open · 2025Article
- Oral Anticoagulation Therapy: An Update on Usage and Costs in the Endemic COVID-19 Era.Journal of clinical medicine · 2025Article
- An Evaluation of Oral Anticoagulant Safety Indicators by England's Community Pharmacies.Pharmacy (Basel, Switzerland) · 2024Article
- Safety of direct-acting oral anticoagulant (DOAC) prescribing: OpenSAFELY-TPP analysis of 20.5 million adults' electronic health records.BJGP open · 2024Article
- Influence of the COVID-19 pandemic on patients receiving oral anticoagulants for the treatment of non-valvular atrial fibrillation.International journal of cardiology. Heart & vasculature · 2024Article
- A Delphi consensus on the management of anticoagulation in the COVID-19 pandemic: the MONACO study.Cardiovascular diagnosis and therapy · 2023Review
- The Japanese Guide affected the prescription of steroids for COVID-19 inpatients during the COVID-19 epidemic in Japan.Scientific reports · 2023Article
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- Identifying unmet antithrombotic therapeutic need, and implications for stroke and systemic embolism in atrial fibrillation patients: a population-scale longitudinal study.European heart journal open · 2022Article
- Deaths from cardiovascular disease involving anticoagulants: a systematic synthesis of coroners' case reports.BJGP open · 2022Article
- Potentially inappropriate prescribing of DOACs to people with mechanical heart valves: A federated analysis of 57.9 million patients' primary care records in situ using OpenSAFELY.Thrombosis research · 2022Article
- Edoxaban Versus Low-Molecular-Weight Heparin in Hospitalized COVID-19 Patients With Atrial Fibrillation.Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/HemostasisObservational
- Impact of the COVID-19 pandemic on cardiovascular heart disease medication use: time-series analysis of England's prescription data during the COVID-19 pandemic (January 2019 to October 2020).Therapeutic advances in cardiovascular diseaseArticle
Corrections and comments
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Authors and funding
32 authors at 4 institutions in 1 country.
Funding
Abstract
backgroundEarly in the COVID-19 pandemic, the National Health Service (NHS) recommended that appropriate patients anticoagulated with warfarin should be switched to direct-acting oral anticoagulants (DOACs), requiring less frequent blood testing. Subsequently, a national safety alert was issued regarding patients being inappropriately coprescribed two anticoagulants following a medication change and associated monitoring.
objectiveTo describe which people were switched from warfarin to DOACs; identify potentially unsafe coprescribing of anticoagulants; and assess whether abnormal clotting results have become more frequent during the pandemic.
methodsWith the approval of NHS England, we conducted a cohort study using routine clinical data from 24 million NHS patients in England.
results20 000 of 164 000 warfarin patients (12.2%) switched to DOACs between March and May 2020, most commonly to edoxaban and apixaban. Factors associated with switching included: older age, recent renal function test, higher number of recent INR tests recorded, atrial fibrillation diagnosis and care home residency. There was a sharp rise in coprescribing of warfarin and DOACs from typically 50-100 per month to 246 in April 2020, 0.06% of all people receiving a DOAC or warfarin. International normalised ratio (INR) testing fell by 14% to 506.8 patients tested per 1000 warfarin patients each month. We observed a very small increase in elevated INRs (n=470) during April compared with January (n=420).
conclusionsIncreased switching of anticoagulants from warfarin to DOACs was observed at the outset of the COVID-19 pandemic in England following national guidance. There was a small but substantial number of people coprescribed warfarin and DOACs during this period. Despite a national safety alert on the issue, a widespread rise in elevated INR test results was not found. Primary care has responded rapidly to changes in patient care during the COVID-19 pandemic.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.