Association of Retinal Microvascular Signs with Incident Atrial Fibrillation: The Multi-Ethnic Study of Atherosclerosis

Abstract

Microvascular diseases may contribute to the occurrence of atrial fibrillation (AF). Retinal microvascular signs that are similar to other microvasculature in the body and can be visualized directly via ophthalmoscopy may provide insights into such a relationship. Prospective, longitudinal, multiethnic study. We examined the association between retinal microvascular signs and incident AF in 4994 participants 47 to 86 years of age and free of prior AF who underwent fundus photography from 2002 through 2004 and were followed up through 2015 in the Multi-Ethnic Study of Atherosclerosis (MESA). Retinal microvascular signs evaluated include central retinal arteriolar equivalent and central retinal venular equivalent (CRVE) and presence of any retinopathy signs (e.g., retinal microaneurysms or hemorrhages). A multivariate Cox regression analysis was used to determine the relationship while adjusting for traditional risk factors, alcohol intake, body mass index, diabetes status, chronic kidney disease status, hemoglobin A1c level, C-reactive protein level, medications, and prevalent cardiovascular diseases or heart failure. Incident AF events were identified using 12-lead electrocardiographic findings, hospital discharge records, and Medicare claims data. During a median follow-up of 14.1 years, 643 AF events were identified. No association was found between any retinal microvascular signs and incident AF except for retinal focal arteriolar narrowing (hazard ratio, 1.75; 95% confidence interval, 1.06-2.87) in the overall population. However, in the subgroup analyses by gender, wider CRVE was associated with a higher risk of incident AF in women, but not in men (hazard ratio for every 10-μm increase in CRVE, 1.08 [95% confidence interval, 1.01-1.15] and 0.97 [95% confidence interval, 0.92-1.03], respectively; P= 0.041 for interaction). No consistent pattern of association was found between retinal microvascular signs and incident AF. We observed an association in women, but not in men, of wider retinal venular calibers with incidence of AF. The reasons for a possible interaction are incompletely understood.