Direct Oral Anticoagulant (DOAC) Dosing in Patients with Non-valvular Atrial Fibrillation (NVAF) in the United Kingdom: A Retrospective Cohort Study Using CPRD Gold Database

Safety of direct-acting oral anticoagulant (DOAC) prescribing: OpenSAFELY-TPP analysis of 20.5 million adults' electronic health records

BACKGROUND

During the COVID-19 pandemic many patients were switched from warfarin to direct-acting oral anticoagulants (DOACs), which require the creatinine clearance (CrCl) calculated to ensure the correct dose is prescribed to avoid bleeding or reduced efficacy.

AIM

To identify the study population proportion prescribed a DOAC. Of these, the proportion with recorded: weight, estimated glomerular filtration rate (eGFR), creatinine, CrCl and atrial fibrillation (AF). To analyse the proportion of patients with recorded AF and CrCl prescribed a recommended DOAC dose.

DESIGN & SETTING

A retrospective cohort study of 20.5 million adult NHS patients' electronic health records (EHRs) in England in the OpenSAFELY-TPP platform (January 2018-February 2023).

METHOD

Patients on DOACs were analysed for age, sex, recorded weight, eGFR, creatinine, CrCl and AF. Prescribed DOAC doses in patients with recorded AF were compared with recommended doses for recorded CrCl and determined as either recommended, higher than recommended (overdose), or lower than recommended (underdose).

RESULTS

In February 2023, weight, eGFR, creatinine, CrCl, and AF were recorded in 72.8%, 92.4%, 94.3%, 73.5%, and 73.9% of study population, respectively. Both AF and CrCl were recorded for 56.7% of patients. Of these, 86.2% received the recommended, and 13.8% non-recommended, DOAC doses.

CONCLUSION

CrCl is not recorded for a substantial number of patients on DOACs. We recommend that national organisations tasked with safety, collectively update guidance on the appropriate weight to use in the Cockcroft-Gault equation, clarify that CrCl is not equivalent to eGFR, and work with GP clinical system suppliers to standardise the calculation of CrCl in the EHR.

Idarucizumab in dabigatran-treated patients with acute stroke: a review and clinical update

Idarucizumab is an antibody fragment specific for the immediate reversal of dabigatran anticoagulation effects. The use of idarucizumab is approved for dabigatran-treated patients suffering from life-threatening or uncontrolled bleeding and those in need of urgent surgery or invasive procedures. Data from randomized controlled clinical trials and real-world experience provide reassuring evidence about the efficacy and safety of idarucizmab use in patients with acute stroke. In this narrative review, we summarize the available real-world evidence and discuss the relevance and importance of idarucizumab treatment in acute stroke patients in everyday clinical practice. In addition, we also discuss special issues like prothrombin complex concentrate application as an alternative to idarucizumab, its application before endovascular therapy, sensitivity of thrombi to lysis, and necessary laboratory examinations.

Kidney function estimators for drug dose adjustment of direct oral anticoagulants in older adults with atrial fibrillation

Background

The Cockcroft-Gault equation (CrClC-G) is recommended for dose adjustment of direct oral anticoagulant drugs (DOACs) to kidney function. We aimed to assess whether defining DOAC dose appropriateness according to various kidney function estimators changed the associations between dose appropriateness and adverse events in older adults with atrial fibrillation (AF).

Methods

Participants of the Berlin Initiative Study with AF and treated with DOACs were included. We investigated CrClC-G and estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration and European Kidney Function Consortium equations based on creatinine and/or cystatin C. Marginal structural Cox models yielded confounder-adjusted hazard ratios for the risk of mortality, thromboembolism and bleeding associated with dose status.

Results

A total of 224 patients were included in the analysis (median age 87 years). Using CrClC-G, 154 (69%) had an appropriate dose of DOACs, 52 (23%) were underdosed and 18 (8%) were overdosed. During a 39-month median follow-up period, 109 (14.9/100 person-years) participants died, 25 (3.6/100 person-years) experienced thromboembolism and 60 (9.8/100 person-years) experienced bleeding. Dose status was not associated with mortality and thromboembolism, independent of the equation. Underdose status was associated with a lower risk of bleeding with all the equations compared with the appropriate dose group. In participants with discrepancies in dose status using CrClC-G and eGFR equations, the occurrence of endpoints did not differ between participants having an appropriate dose using CrClC-G or eGFR.

Conclusion

In older adults with AF, the association of DOAC dose status with adverse events did not differ when using CrClC-G or eGFR. Our results suggest that eGFR equations are not inferior to CrClC-G within this context.