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Fundus Photography as a Convenient Tool to Study Microvascular Responses to Cardiovascular Disease Risk Factors in Epidemiological Studies
Published on: October 22, 2014
POSTERIOR FUNDUS HEMORRHAGES: Frequency and Associated Factors: The Beijing Eye Study
Jin Qiong Zhou1, Ya Xing Wang2, Liang Xu2
1Beijing Key Laboratory of Intraocular Tumor Diagnosis and Treatment, Beijing Ophthalmology and Visual Science Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
Purpose:
To examine frequency and associations of retinal hemorrhages.
Methods:
The population-based Beijing Eye Study included 3,468 individuals. Monoscopic fundus photographs were examined for hemorrhages.
Results:
Retinal hemorrhages were detected in 515 eyes (429 individuals) (prevalence: 7.6%; 95% confidence interval [CI]: 7.0-8.0 per eye; 12.7%; 95% CI: 11.7-13.7 per person). Higher prevalence of retinal hemorrhages was correlated (multivariate analysis) with higher systolic blood pressure (P < 0.001; odds ratio: 1.02; 95% CI: 1.01-1.03), higher prevalence of diabetic retinopathy (P < 0.001; odds ratio: 121; 95% CI: 61-240), and higher prevalence of retinal vein occlusions (P < 0.001; odds ratio: 27; 95% CI: 17-42). Retinal hemorrhages were due to diabetic retinopathy (189 [36.7%] eyes), retinal vein occlusions (n = 65 [12.6%]), posterior vitreous detachment (n = 23 [4.5%]), glaucoma (n = 14 [2.7%]), exudative age-related macular degeneration (n = 8 [1.6%]), hypertensive retinopathy (n = 10 [1.9%]), and exudative myopic maculopathy (n = 1 [0.2%]). Retinal hemorrhages without evident ocular cause ("NOH") were detected in 204 (3.0%) eyes (or 39.6% of all retinal hemorrhages). Higher prevalence of NOHs was correlated with higher systolic blood pressure (P < 0.001; odds ratio: 1.02; 95% CI: 1.01-1.03) after adjusting for blood glucose concentration and prevalence of cortical cataract.
Conclusion:
In a population-based recruited cohort of individuals aged 50+ years, prevalence of any fundus hemorrhage was about 8% per eye and 13% per individual. Approximately 60% of the hemorrhages were due to ocular reasons, mainly diabetic retinopathy, retinal vein occlusions, and posterior vitreous detachment, whereas 40% of the bleedings were not evidently associated with ophthalmologic causes but strongly with elevated systolic blood pressure.
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