Study type

Study type

Non-interventional study

Scope of the study

Drug utilisation
Study drug and medical condition

Anatomical Therapeutic Chemical (ATC) code

(B01AE07) dabigatran etexilate
dabigatran etexilate
(B01AF01) rivaroxaban
rivaroxaban
(B01AF02) apixaban
apixaban
(B01AF03) edoxaban
edoxaban
(B01AA03) warfarin
warfarin

Medical condition to be studied

Atrial fibrillation
Population studied

Age groups

Adults (75 to < 85 years)
Adults (85 years and over)

Estimated number of subjects

168000
Study design details

Main study objective

1) To describe changes in the point prevalence and incidence of OAC prescribing by year2) To describe switching between OACs during the study period3) To compare the characteristics of patients with AF who were newly started on OACs tothose who weren't during 3 study periods: 2003-2007, 2008-2012, 2013-2017.4) To describe persistence with DOACs compared with warfarin

Data analysis plan

Point prevalence of OAC prescribing will be calculated at the midpoint of each year.The incidence of OAC prescribing will be calculated overall and for each specific OAC.Everyone in the cohort will be considered 'at risk' until the time they receive their first OAC prescription. For the person-time at risk calculation the denominator will be truncated at the date of their first OAC prescription. Incidence will be stratified by age (75-84 and 85+) and sex. The number and percentage of patients switching OAC will be calculated. The number of patients with multiple switches and details of the switches will be described. Average time to switch will be reported. Demographics, characteristics, co-morbidities and concomitant medications will be reported for each period in the no OAC, DOAC and warfarin groups.Duration of prescribing of DOACs will be compared to warfarin using Cox-proportional hazards, stratified by DOAC and adjusted for age and other important covariates, if feasible.