Treatment patterns for oral anticoagulants in older patients with atrial fibrillation: a retrospective, cross-sectional, nationwide study from Denmark

Abstract

Objectives: Atrial fibrillation (AF) is a predominant risk factor of ischaemic stroke and treatment with oral anticoagulants (OACs) is recommended in all patients with risk factors. This study sought to examine treatment patterns of OACs in older patients with AF.

Design: Retrospective, cross-sectional study.

Setting: Danish nationwide administrative and clinical registers and databases.

Participants: A total of 40 027 patients, >75 years of age, after their first hospital contact due to AF between 2010 and 2018.

Primary and secondary outcomes measures: The primary event of interest was claimed prescriptions for OACs within 180 days after first hospital contact due to AF. Proportions of patients treated with OACs were estimated and clinical factors associated with the probability of receiving OAC treatment were identified using adjusted logistic regression models.

Results: A total of 40 027 patients were included with a slight majority of women (54%). The median age was 81 years (IQR 78-86). We found that an overall 32 235 patients (81%) were prescribed an OAC after their first hospital contact due to AF with a marked increase in the proportion of patients treated from 2010 to 2018. Factors related to a decreased probability of receiving treatment were bleeding risk factors such as a history of haemorrhagic stroke (OR 0.21, 95% CI 0.16 to 0.27), any bleeding (OR 0.58, 95% CI 0.53 to 0.62) as well as markers of frailty such as osteoporosis (OR 0.78, 95% CI 0.71 to 0.85).

Conclusion: In this large nationwide study, we found that in older patients with AF, the overall rates of OAC prescription were generally high (~80%) and increasing during the last decade. Factors associated with not receiving guideline recommended OAC treatment were generally related to bleeding risk factors or frailty.

Keywords: adult cardiology; anticoagulation; clinical pharmacology; thromboembolism.

Figure 1

Patient streated with oral anticoagulants (OAC), by age plot depicting the proportion of patients treated with OACs by age (blue curve). The red bar charts depict the number of patients in each age category. The x-axis illustrates age in years and the left y-axis shows the proportion of patients treated with OACs in percentage (%). The right y-axis depicts the absolute number of patients.

Figure 2

Proportion of patients receiving treatment with oral anticoagulants (OACs) by calendar year the x-axis illustrates year and the y-axis the proportion in percentage (%).

Figure 3

Forest plot depicting the association between clinical factors and the odds of receiving treatment oral anticoagulants (OAC) the x-axis illustrates ORs with 95% CI and the investigated factors are depicted on the y-axis. CNS, central nervous system; COPD, chronic obstructive pulmonary disease; DAPT, dual antiplatelet therapy; NSAID, non-steroidal anti-inflammatory drugs; PPI, proton-pump inhibitor.