RETINAL EMBOLI AND STROKE: THE BEAVER DAM EYE STUDY

Objective To describe the prevalence at baseline and the 5-year incidence of retinal emboli, associated risk factors, and the relationship of retinal emboli at baseline to stroke and ischemic heart disease mortality. Methods The Beaver Dam Eye Study is a large (N=4926) population-based study of persons aged 43 to 86 years at the baseline examination. Retinal emboli were detected at baseline (1988-1990) and at a 5-year follow-up (1993-1995) by grading of stereoscopic 30° color fundus photographs using standardized protocols. Cause-specific mortality was determined from death certificates. Results The prevalence of retinal arteriolar emboli was 1.3%, and the 5-year incidence was 0.9%. After adjustments were made for age and sex, the prevalence of retinal emboli was associated with higher pulse pressure, hypertension, diabetes mellitus, past and current smoking, cardiovascular disease, and the presence of retinopathy. After adjustments were made for age and sex, the incidence of retinal emboli was associated with past and current smoking and a history of coronary artery bypass surgery. After age, sex, and systemic factors were controlled for, people with retinal emboli had a significantly higher hazard of dying with a mention of stroke on the death certificate (hazard ratio=2.61, 95% confidence interval=1.12-6.08) than those without retinal emboli. Conclusions Persons with retinal emboli are at an increased risk of stroke-related death. Data also show an association of smoking, hypertension, and cardiovascular disease with the prevalence of retinal emboli. Clinical Relevance Data from this population-based study suggest that after discovery of retinal emboli in the asymptomatic patient, referral for possible medical intervention to control hypertension, if present, may be beneficial.