Non-Valvular Atrial fibrillation (NVAF) is a quivering or irregular heartbeat that can lead to blood clotting, which can lead to stroke, heart attacks (blocked arteries) or other thromboembolism (blocked blood vessels) in other parts of the body. It is typically treated using anticoagulants (blood thinners), which prevent the formation of blood clots. Direct Oral Anti Coagulants (DOACs) are recommended in the UK for the prevention of clots. In every day clinical practice, it is essential that patients receive the correct dose of DOAC as under-dosing can lead to clot formation and overdosing can lead to bleeding. The dose is adjusted depending on whether a patient has certain conditions such kidney failure in which case the dose will be lowered. The aim of this research is to understand how DOACs (apixaban, rivaroxaban, dabigatran and edoxaban) are used in the UK and whether the doses they received were under or over the recommended dose. It will also describe the patients’ characteristics and other factors that may affect how they benefit from their DOAC treatment. With this information, this study will investigate the occurrence of strokes, major bleeding, embolism and mortality according the whether they are doses correctly or have received an under- or overdosing of DOACs.
The study will review the records, within the CPRD Gold, of patients with NVAF who initiated treatment with a DOAC from 1st January 2016 to 30th June 2019. Each patients will have their characteristics described going back 24 months before they started using DOAC.
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.
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 ( UK )
Yousef Zawaneh - Corresponding Applicant - LA-SER Europe Ltd ( UK )
Farhan Mughal - Collaborator - Daiichi Sankyo Co. Ltd.
gaelle gusto - Collaborator - LA-SER Europe Ltd ( UK )
Georgios Spentzouris - Collaborator - Daiichi Sankyo Europe GmbH
Jolanta Wrotniak-Vucic - Collaborator - LA-SER Europe Ltd ( UK )
Umesh Doobaree - Collaborator - LA-SER Europe Ltd ( UK )
HES Admitted Patient Care;ONS Death Registration Data