Abstract
Purpose: :
To determine the prevalence of retinal diseases and their pattern in Tehran through a population–based study.
Methods: :
In 2002 through a stratified random cluster sampling, 6497 citizens representing a cross–section of the population of Tehran were selected from 160 clusters. Eligible people were recruited through a door–to–door household survey in the selected clusters and transferred to a clinic for an extensive eye examination and interview. Direct and indirect ophthalmoscopy was performed and the retina was examined systematically.
Results: :
A total of 4565 people participated and had interviews and examinations; a response rate of 70.3%. The prevalence of retinal diseases was 8.0% (95% CI, 7.2% to 8.7%); 3.7% among patients younger than 40 years old and 20.9% among patients of equal or older than 40. The prevalence of retinal diseases increased with increasing age (P value<0.001). Peripheral retinal lesions (3.5%; 95% CI, 2.1 to 4.8) and age related macular degeneration (AMD) (2.7%; 95% CI, 2.2 to 3.2) were the most common retinal diseases. Refractive errors and cataract were the major ocular co–morbidities, high blood pressure and diabetes were the main systemic co–morbidities. Blindness (Best Corrected Visual Acuity < 3/60, in the better eye) was detected in 2 patients (0.4%; 95% CI, 0.1 to 0.9) and three patients (0.6%; 95% CI, 0.01 to 1.1) had low vision (3/60< Best Corrected Visual Acuity < 6/18, in the better eye). Prevalence of diabetic retinopathy was 0.6%. Non proliferative diabetic retinopathy (0.4%) was the most common type. In diabetic patients 1.3% had clinical evidence of diabetic retinopathy. Linear regression modeling revealed two major determinants for the occurrence of diabetic retinopathy namely patients’ age and cigarette smoking. Druzen (1.7%; 95% CI, 0.8 to 2.3) and geographic atrophy (0.5%; 95% CI, 0.2 to 0.9) were the most common type of AMD.
Conclusions: :
These findings reveal a high prevalence of retinal diseases in the population. Peripheral retinal lesions and AMD were the most common retinal diseases. Our findings should be considered for case finding and treatment programs for specific retinal diseases.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • age-related macular degeneration • diabetic retinopathy