Retinal arteriolar emboli and long-term mortality: Pooled data analysis from two older populations

BACKGROUND AND PURPOSE - To assess the relationship between retinal arteriolar emboli and mortality in older people. METHODS - Pooled data from 2 population-based cohort studies. At baseline, the Beaver Dam Eye Study (BDES) examined 4926 persons 43 to 86 years of age (1988 to 1990), and the Blue Mountains Eye Study (BMES) examined 3654 persons 49 to 97 years of age (1992 to 1994). Retinal arteriolar emboli were assessed by grading retinal photographs using standardized methods. Deaths and causes of death were determined from death certificates or Australian National Death Index. Cox regression models were used to estimate mortality hazard ratios (HRs) associated with emboli, adjusting for age, gender, body mass index, hypertension, diabetes, smoking, serum total cholesterol, high-density lipoprotein cholesterol, study site, and past histories of stroke, angina, and acute myocardial infarct. RESULTS - Of 8580 baseline participants, 8384 (98%) had retinal photographs available, and 111 showed retinal arteriolar emboli (BDES n=61; BMES n=50). Over 10 to 12 years, 2506 participants (30%) died, including 344 (4%) from stroke-related and 1315 (16%) from cardiovascular causes. The cumulative mortality rates were higher in participants with than without emboli (all-cause 56% versus 30%; stroke-related 12% versus 4.0%; cardiovascular 30% versus 16%). The increased mortality risk associated with emboli was independent of age, gender, other vascular risk factors, and past histories of stroke or heart disease for all-cause (multivariate-adjusted HR, 1.3; CI, 1.0 to 1.8) and stroke-related mortality (HR, 2.0; CI, 1.1 to 3.8) but not for cardiovascular mortality (HR, 1.2; CI, 0.8 to 1.7). CONCLUSIONS - Our pooled data from 2 older populations suggest that retinal emboli predict a modest increase in all-cause and stroke-related mortality independent of cardiovascular risk factors.