Direct oral anticoagulants (DOAC) dosing patients with non-valvular atrial fibrillation (NVAF): a retrospective cohort study using the Clinical Practice Research Datalink (CPRD) Gold database

Date of Approval
Application Number
Technical Summary

NVAF is an atrial tachyarrhythmia characterized by predominantly uncoordinated atrial activation with consequent deterioration of atrial mechanical function. European Society of Cardiology (ESC) Guidelines (2020) have underlined the importance of direct oral anticoagulants (DOAC) for stroke prevention compared to standard anticoagulants in NVAF. One of the major problems with the management of DOACs is that in routine practice, doses are often inconsistent with drug labelling which may be associated with worse outcomes. The aim of this study is to investigate DOAC (apixaban, rivaroxaban, dabigatran and edoxaban) dosing patterns and associated outcomes in patients treated in routine clinical practice in the UK.
This study will employ a retrospective cohort design and will source its study population from the CPRD Gold. All NVAF patients who initiated treatment with a DOAC (apixaban, rivaroxaban, dabigatran, or edoxaban) from the 1st January 2016 to 30th June 2019 will be included in the study. Patients with a history of end stage renal failure, venous thromboembolism, or valvular heart surgery. Anyone with more than one DOAC or has received heparin at initiation of a DOAC in the study period or had a fracture or surgery to the knee, hip or pelvis will be excluded too. The study will aim to describe the demographic, clinical characteristics, treatment pattern, including dose (underdosing, standard dosing), duration, switching, and discontinuation, of NVAF patients on DOAC treatments and the clinical outcomes in patients on a reduced dose with no indication for dose reduction.

Health Outcomes to be Measured

1- Major bleeding (bleeding leading to hospitalization)
2- Stroke (any; hemorrhagic stroke; ischemic stroke)
3- Systemic embolism
4- All-cause mortality


Artak Khachatryan - Chief Investigator - LA-SER Europe Ltd ( Certara )
Yousef Zawaneh - Corresponding Applicant - LA-SER Europe Ltd ( Certara )
Farhan Mughal - Collaborator - Daiichi Sankyo
gaelle gusto - Collaborator - LA-SER Europe Ltd ( Certara )
Georgios Spentzouris - Collaborator - Daiichi-Sankyo Europe
Jolanta Wrotniak-Vucic - Collaborator - LA-SER Europe Ltd ( Certara )
Umesh Doobaree - Collaborator - LA-SER Europe Ltd ( Certara )


HES Admitted Patient Care;ONS Death Registration Data