Risk of stroke in retinal vein occlusion

Objective:To investigate risk and risk periods for stroke and acute myocardial infarction (AMI) with incident retinal vein occlusion (RVO).Methods:Data from the Korean national claims database (2007-2011) was analyzed, which covers the entire Korean population (48 million). Of the incident RVO cases, RVO cases with incident stroke/AMI during the observation period (RVO occurrence 365 days) were identified. In this self-controlled case series, the risks of incident stroke/AMI were compared between the control and risk periods by calculating the relative incidence rate ratios (IRRs) for stroke/AMI.Results:Of the 44,603 patients with incident RVO in 2009-2010, 1,176 patients experienced incident stroke/AMI (853 ischemic strokes, 163 hemorrhagic strokes, 172 AMIs) during their observation period. The risk of stroke/AMI increased throughout the entire risk period; the IRR was highest during the first 30 days after RVO occurrence (2.66; 95% confidence interval, 2.06-3.43). Analysis limited to ischemic stroke resulted in similar findings. Analysis limited to hemorrhagic stroke showed an increased risk during the first 30 days after RVO occurrence (IRR, 3.45; 95% confidence interval, 1.80-6.59) as well as the 31 to 90 days before and 91 to 180 days after RVO occurrence. However, the risk was not increased during any risk periods in the analysis limited to AMI.Conclusions:The present study provides new evidence that patients with incident RVO are at increased risk of stroke just after RVO occurrence. Immediate risk evaluation and proper treatment of stroke risk factors in patients with RVO are needed to reduce stroke-related mortality and morbidity.