Antithrombotic treatment for retinal vein occlusion. A systematic review and meta-analysis

Background: Retinal vein occlusion (RVO) represents a common thrombotic disorder. Objectives: In this meta-analysis, we evaluated the efficacy and safety of anticoagulant and antiplatelet therapy in RVO. Methods: MEDLINE and EMBASE were searched up to December 2021 for observa- tional studies and randomized controlled trials including patients with RVO. Efficacy outcomes were best-corrected visual acuity improvement, recurrent RVO, fluorescein angiography improvement, cardiovascular events, and safety outcomes were major bleeding and intraocular bleeding. Results: A total of 1422 patients (15 studies) were included. Antiplatelet therapy was administered to 477 patients (13 studies), anticoagulant therapy to 312 patients (12 studies), and 609 (7 studies) patients received no antithrombotic treatment. The treatment duration ranged between 0.5 and 3 months. The median follow-up duration was 12 months. Best-corrected visual acuity improvement was reported in 58% of the patients (95% confidence interval [CI], 45%-69%) overall, 64% (95% CI, 58%-71%) in those on anticoagulant therapy, and 33% (95% CI, 21%-47%) in those on antiplatelet therapy. The rates of recurrent RVO was 11% (95% CI, 7%-17%), 7% (95% CI, 2%-19%), and 15% (95% CI, 8%-28%), respectively. The rate of recurrent RVO in untreated pa- tients was 9% (95% CI, 6%-14%). The rate of major bleeding was 5% (95% CI, 3%-9%) overall, 4% (95% CI, 2%-9%) in those on anticoagulant therapy, and 7% (95% CI, 2%- 23%) in those on antiplatelet therapy. Conclusion: Anticoagulant therapy was associated with higher visual acuity improve- ment and fewer recurrent RVO events than antiplatelet therapy, at the cost of an acceptable proportion of bleeding complications.