Retinal microvascular changes and subsequent vascular events after ischemic stroke

Retinal microvasculature changes are associated with vascular events including stroke in healthy populations. It is not known whether retinal microvascular changes predict recurrent vascular events after ischemic stroke. We examined the relationship between retinal microvascular signs and subsequent vascular events in a prospective cohort of 652 acute ischemic stroke patients admitted to a tertiary hospital in Singapore from 2005 to 2007. Retinal photographs taken within 1 week of stroke onset were assessed in a masked manner for quantitative and qualitative measures. Follow-up data over 2-4 years were obtained by standardized telephone interview and then were verified from medical records. Predictors of recurrent vascular events (cerebrovascular, coronary, vascular death, and composite vascular events) were determined using Cox regression models. Follow-up data over a median of 29 months were obtained for 89% (652 patients) of the cohort. After adjustment for covariates including traditional risk factors and index stroke etiology, patients with severe arteriovenous nicking (AVN) were more likely to have a recurrent cerebrovascular event (hazard ratio [HR] 2.28, 95% confidence interval [CI] 1.20-4.33) compared with those without AVN. Patients with severe focal arteriolar narrowing (FAN) were more likely to have a recurrent cerebrovascular event (HR 2.75, 95% CI 1.14-6.63) or subsequent composite vascular event (HR 2.77, 95% CI 1.31-5.86) compared to those without FAN. Retinal microvascular changes predicted subsequent vascular events after ischemic stroke, independent of traditional risk factors and stroke subtype. Thus, retinal imaging has a potential role in predicting the risk of recurrent vascular events after ischemic stroke and in understanding novel vascular risk factors.