Older patients with atrial fibrillation who have contraindications to oral anticoagulation (OAC) because of high bleeding risk have increased mortality compared with untreated patients who have no contraindications, according to a recent study published in JACC: Clinical Electrophysiology.

Study researchers conducted an observational, longitudinal analysis comparing patients with and without contraindications to OAC based on ischemic and bleeding outcomes during a 3-year period. Using patients diagnosed in 2007 with prevalent atrial fibrillation and a CHA2DS2-VASc score ≥2 who were 65 years or older and living in the United States, study researchers analyzed nationally representative files of a 5% sample of Medicare beneficiaries. Because the study period (2007-2010) occurred before the use of non–vitamin K antagonist oral anticoagulants, study researchers defined OAC as the use of warfarin. Contraindications to warfarin included 1 or more instances of intracranial hemorrhage or mass, gastrointestinal bleeding, end-stage liver disease, and blood dyscrasia. Exclusions included certain patients enrolled in Medicare managed care and those who had a change in anticoagulation status, resulting in a primary study population of 26,684 patients not receiving oral anticoagulation. 

Related Articles

The primary analysis (contraindications and outcomes without OAC) illustrated that when a contraindication to warfarin was present, it was significantly associated with death (hazard ratio [HR], 1.17; 95% CI, 1.12-1.22; P <.001), gastrointestinal bleed (adjusted HR, 2.31; 95% CI, 1.64-3.24; P <.001), and hospitalization (adjusted HR, 1.20; 95% CI, 1.16-1.24; P <.001). 

The secondary analysis (OAC use and contraindications) showed a significant association with a lower risk for death (adjusted HR, 0.79; 95% CI, 0.76-0.83; P <.001), stroke (adjusted HR, 0.90; 95% CI, 0.83-0.99; P =.03), and hospitalization (adjusted HR, 0.93; 95% CI, 0.90-0.96; P <.001) among patients using OACs.

However, this group had a significantly higher risk for intracranial hemorrhage (adjusted HR, 1.42; 95% CI, 1.17-1.72; P <.001). 

Although the study did not include patients who had been treated with non–vitamin K antagonist OACs, study researchers thought that evidence from sensitivity analyses was “consistent with topline results.” Additional limitations included observational data, a heterogeneous sample, and difficulty defining objective criteria for oral anticoagulation contraindications.

Despite these limitations, study researchers concluded by noting “the use of OAC is associated with lower rates of all-cause stroke, hospitalization, and death, but higher risk of [intracranial hemorrhage].” Further, they noted that “future research should identify subgroups in which the net clinical benefit favors [oral anticoagulation] in these high bleeding-risk patients versus other potential treatment modalities such as left atrial appendage occlusion.”

Disclosures: This study was supported by Boston Scientific. Please see the original reference for a full list of authors’ disclosures. 

Reference

Steinberg BA, Ballew NG, Greiner MA, et al. Ischemic and bleeding outcomes in patients with atrial fibrillation and contraindications to oral anticoagulation [published online October 2, 2019]. JACC Clin Electrophysiol. doi:10.1016/j.jacep.2019.07.011