Retinal Microvascular Signs and the Long-term Risk of Stroke

Abstract

Purpose: : Retinal vascular abnormalities have been related to several age-related cerebrovascular diseases. However, data on the prediction of long-term risk of stroke are lacking. We aimed to examine the association between retinal microvascular abnormalities and the long-term risk of stroke and stroke subtypes.

Methods: : A total of 10,650 participants age 49-73 at the 1993-1995 examination, who had gradable retinal photographs, no history of stroke at baseline and data on incident stroke, were included from the Atherosclerosis Risk In Communities (ARIC) Study. Trained graders assessed the retinal photographs for qualitative retinopathy signs (i.e., retinal mircoaneurysms, hard and soft exudates, haemorrhages) and retinal arteriolar signs (focal arteriolar narrowing and arterio-venous nicking) and quantitative indices of vascular caliber (central retinal arteriole and venule equivalents). Incident events of stroke and its subtypes cerebral infarction and intracerebral hemorrhage were identified and validated via case record review over time.

Results: : After a mean follow-up period of 13 years, 503 persons developed an incident stroke, of which 444 were cerebral infarctions and 47 intracerebral hemorrhages. After adjustment for age, gender, race, center, mean arterial blood pressure and other stroke risk factors, participants with any signs of retinopathy were at an increased risk of developing a stroke [hazard ratios (HR): 1.99; 95% confidence intervals (CI): 1.50-2.64], as were persons with arterio-venous nicking [HR: 1.33; 95%CI: 1.06-1.67]. When examining stroke subtypes, presence of retinopathy signs [HR: 1.85; 95% CI: 1.36-2.51] and arterio-venous nicking [HR: 1.33; 95% CI: 1.05-2.69] was associated with cerebral infarction. Results remained similar after stratification for diabetic status. Neither retinal arteriolar, venular calibre nor focal arteriolar narrowing was associated with the risk of incident stroke and its subtypes.

Conclusions: : Retinopathy is associated with long-term stroke risk, independent of traditional stroke risk factors, particularly in relation to cerebral infarctions.

Keywords: retina • imaging/image analysis: clinical • clinical (human) or epidemiologic studies: risk factor assessment