JAMA Ophthalmology, October 2017
Population-based data on retinal emboli in Asia are limited. In the Singapore Epidemiology of Eye Disease Study, Cheung et al. examined prevalence and risk factors among a large group of Chinese, Malay, and Indian patients. They found that retinal emboli were most common among the Indian individuals and were associated with chronic kidney disease as well as classic cardiovascular factors.
This cross-sectional study included 9,978 patients (40-80 years of age) with gradable retinal photographs. Of these, 88 exhibited retinal emboli, which were identified using a standardized protocol. Age-standardized prevalence of retinal emboli was calculated from the 2010 Singapore adult population. Interviews, lab tests, and comprehensive systemic and ophthalmic exams were performed to determine risk factors associated with retinal emboli.
The overall person-specific, age-standardized prevalence of retinal emboli was 0.75%. Prevalence rates in the Indian, Chinese, and Malay cohorts were 0.98%, 0.73%, and 0.44%, respectively. According to multivariable-adjusted analysis, common risk factors for retinal emboli were older age, Indian ethnicity, hypertension, chronic kidney disease, and history of stroke.
Elevated creatinine levels and low glomerular filtration rates were consistently linked to retinal emboli, independent of age, smoking status, concomitant hypertension, and other risk factors. Stratified analyses showed a similar correlation between retinal emboli and reduced renal function, even for participants without hypertension or diabetes. The odds of developing chronic kidney disease were twice as great among individuals with retinal emboli.
Of note, some of these relationships had not been identified in previous population-based studies.
The authors concluded that the presence of retinal emboli may signal vascular embolic damage to the brain as well as the kidneys. If their findings are confirmed by longitudinal studies, it would be prudent to ensure that patients with retinal emboli receive both a renal evaluation and a cardiovascular assessment. (Also see related commentary by Robert N. Frank, MD, in the same issue.)
The original article can be found here.