Low-Dose Edoxaban Reduces Stroke incidence in Older Patients with Atrial Fibrillation

New findings suggested a once-daily 15-mg dose of edoxaban was superior to placebo in prevention of stroke or systemic embolism in patients 80 years or older with atrial fibrillation (AF).

The prespectified subanalysis of the ELDERCARE-AF trial showed that very low-dose edoxaban had consistent reductions across 3 age strata (80 to 84 years, 85 to 89 years, and ≥90 years), with a numerically higher risk of major or clinically relevant non major bleeding without an interaction with age.

“Although there was no fatal bleeding in the edoxaban group, a careful attention to bleeding risk, especially to gastrointestinal bleeding, needs to be given when treating the extremely older patients with 15-mg edoxaban,” wrote study author Masaru Kuroda, MD, PhD, Department of Cardiology, Akashi Medical Center.

Findings from the phase 3 ELDERCARE-AF found no influence of age on the effect of edoxaban on stroke or systemic embolism, but it was unclear whether the effects remained consistent in extremely older patients, such as those 90 years or older.

This analysis was conducted from August 2016 to December 2019, wherein patients with AF aged ≥80 years who were not considered candidates for standard-dose oral anticoagulants (OACs) were included.

Patients were considered ineligible for OACs for reasons including low creatinine clearance (15 - 30 mL per minute), history of bleeding from a critical area/organ or gastrointestinal bleeding, low body weight (≤45 kg), continuous use of nonsteroidal anti-inflammatory drugs, or concomitant use of antiplatelet drugs.

Eligible patients were recruited randomly from 164 hospitals in Japan and randomly assigned 1:1 to edoxaban or placebo. A total of 984 patients were randomly assigned, with 492 patients in the edoxaban group and 492 patients in the placebo group. Data show the mean age was 82.2 years in the 80 - 84 year age group, 86.8 years in the 85 - 89 year age group, and 92.3 years in the 90 years or older age group.

Within the placebo group, the estimated event rates for stroke or systemic embolism increased with age. The rates were 3.9% per patient-year in the group aged 80 - 84 years (n = 181), 7.3% per patient-year in the group aged 85 to 89 years (n = 184), and 10.1% per patient-year in the group aged 90 years or older (n = 127).

Investigators observed a 15-mg dose of edoxaban had consistent reductions in event rates for stroke or systemic embolism, with no interaction for age (80 - 84 years, hazard ratio [HR], 0.41; 95% CI, 0.13 - 1.31, P = .13; 85 - 89 years, HR, 0.42; 95% CI, 0.17 - 0.99, P = .05; ≥90 years, HR, 0.23; 95% CI, 0.08 - 0.68; P = .008; interaction P = .65).

Further, in the edoxaban group, major bleeding occurred in 5 of 173 patients (2.2% per patient-year) in the group aged 80 to 84 years, 5 of 190 patients (2.2% per patient-year) in the group aged 85 to 89 years, and 10 of 129 patients (6.5% per patient-year) in the group ≥90 years.

No interaction for age was observed in the incidence of major bleeding (80 - 84 years, HR, 5.27; 95% CI, 0.61 - 45.36, P = .13; 85 - 89 years, HR, 0.74; 95% CI, 0.24 - 2.33, P = .61; ≥90 years, HR, 3.02; 95% CI, 0.82 - 11.21, P = .10; interaction P = .15).

In both the placebo and edoxaban groups, the incidence of all-cause death increased with age, with no difference between the edoxaban and placebo groups in all age subgroups.

The study, “Effect of 15-mg Edoxaban on Clinical Outcomes in 3 Age Strata in Older Patients With Atrial Fibrillation: A Prespecified Subanalysis of the ELDERCARE–AF Randomized Clinical Trial,” was published in JAMA Cardiology.