Risk of Intraocular Bleeding With Warfarin Versus Novel Oral Anticoagulants
JAMA Ophthalmology, August 2017
Intraocular hemorrhage is a rare but well-documented effect of warfarin and other antithrombotic agents. Novel oral anticoagulants (NOACs) have shown antithrombotic efficacy equivalent or superior to that of warfarin and are less likely to cause intracranial hemorrhage. Sun et al. performed a systematic review and meta-analysis demonstrating that the risk of intraocular hemorrhage was lower with NOACs than with warfarin.
The authors searched Medline, ClinicalTrials.gov, and article bibliographies for phase 3 randomized controlled trials published before August 2016 that involved patients with atrial fibrillation or venous thromboembolism who received warfarin or a NOAC (i.e., rivaroxaban, apixaban, edoxaban, or dabigatran). Two independent investigators selected the trials to be analyzed. All chosen studies contained data on intraocular bleeding, which were pooled using inverse-variance, weighted, fixed-effects meta-analysis. The primary outcome measures were intraocular bleeding events and associated risk ratio for NOACs versus warfarin. In secondary analyses, the trials were stratified by indication for anticoagulation and type of NOAC.
Twelve trials (7 on atrial fibrillation, 5 on thromboembolism) involving 102,627 patients were included in the analysis. The reduction in intraocular bleeding was 22% lower for NOACs. No significant heterogeneity was observed among the trials. In subgroup analyses, the risk of intraocular bleeding also proved lower for NOACs, and there was no significant difference in the indication for anticoagulation or the type of NOAC used. Summary effects did not differ materially.
In conclusion, the risk of intraocular bleeding was substantially lower with NOACs than with warfarin. Benefits were observed across indications for anticoagulation and types of NOAC. The findings are particularly relevant for patients at increased risk for spontaneous retinal bleeding and may have implications for perioperative care. Future research efforts should be directed at optimizing the management of patients with concomitant ocular disease and cardiovascular disorders.
The original article can be found here.