UCL Institute of Health Informatics


Preprint coverage: Evaluation of antithrombotic use and COVID-19 outcomes in a nationwide cohort

9 September 2021

Preprint by IHI's researchers: "Evaluation of antithrombotic use and COVID-19 outcomes in a nationwide atrial fibrillation cohort"

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Contributors include IHI's Alex Handy, Amitava Banerjee, Caroline Dale, Christopher Tomlinson, Johan Thygesen, Mehrdad Mizani, Michail Katsoulis, Reecha Sofat, Richard Dobson, Rohan Takhar and Spiros Denaxas.

Anticoagulants (AC), a sub-class of antithrombotics (AT), reduce the risk of stroke and are recommended for individuals with atrial fibrillation (AF) and at high risk of stroke (CHA2DS2-VASc score>=2, National Institute for Health and Care Excellence threshold). However, previous evaluations suggest that up to one third of these individuals may not be taking AC. Over estimation of bleeding and fall risk in elderly patients have been identified as potential factors in this under-medicating.

In response to the COVID-19 pandemic, several observational studies have observed correlations between pre-existing AT use, particularly anticoagulants (AC), and lower risk of severe COVID-19 outcomes such as hospitalisation and death. However, these correlations are inconsistent across studies and have not compared all major sub-types of AT in one study.

This study uses datasets covering primary care, secondary care, pharmacy dispensing, death registrations, multiple COVID-19 diagnoses routes and vaccination records for 56 million people in England and is the largest scale evaluation of AT use to date. This provides the statistical power to robustly analyse targeted sub-types of AT and control for a wide range of potential confounders. All code developed for the study is opensource and an updated nationwide evaluation can be rapidly created for future time points.

Read the full paper

For more information please get in touch with: Alex Handy (a.handy@ucl.ac.uk)