Newer Anticoagulants May Reduce Intraocular Bleeding

The risk of intraocular bleeding was reduced by one-fifth when using newer oral anticoagulants compared to using warfarin (Coumadin and other brands), according to a recent study.

In a meta-analysis, published in the August 2017 issue of JAMA Ophthalmology, researchers reviewed several randomized clinical trials published before August 2016.

Michelle T. Sun, MBBS, PhD, of the South Australian Institute of Ophthalmology at University of Adelaide in Australia, and her colleagues reviewed data from more than 102,000 patients who had atrial fibrillation or venous thromboembolism and who had been enrolled in 12 randomized Phase III clinical trials. The studies had compared a novel oral anticoagulant (dabigatran, rivaroxaban, apixaban, or edoxaban) with warfarin and also included data on intraocular bleeding events. This information was then pooled using an inverse-variance, weighted, fixed-effects meta-analysis to look for findings across the studies.

The main outcome for this meta-analysis was intraocular bleeding events and associated risk for newer oral anticoagulants and warfarin. There was no significant heterogeneity observed. Novel oral anticoagulants are also known as non-vitamin K oral anticoagulants.

The researchers found that newer oral anticoagulants were associated with a 22% relative reduction in intraocular bleeding compared with warfarin.

“Our data have particular relevance for patients at higher risk of spontaneous retinal and subretinal bleeding,” the researchers wrote. “These findings may also have important implications in the perioperative period, in which the use of novel oral anticoagulants may be superior,” the researchers noted.

There were no significant differences in results according to the type of novel oral anticoagulant used or to the indication for anticoagulation treatment. The benefits were seen to be similar in both patients with atrial fibrillation and venous thromboembolism.

Intraocular bleeding can lead to visual impairment or loss of vision in an eye. Although these results are suggestive that newer anticoagulants could reduce the risk of intraocular bleeding, more epidemiologic study is needed to determine the optimal management of patients who have both ophthalmic disease and cardiovascular comorbidities requiring anticoagulants, according to the researchers.