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Blindness and low vision in southeast Turkey
A D Negrel1, D C Minassian, F Sayek
1Programme for the Prevention of Blindness, WHO, Geneva, Switzerland.
Ophthalmic Epidemiology
|December 1, 1996
Summary
A population-based survey in southeast Turkey revealed a high prevalence of blindness, 8 times that of the European Economic Community. Cataract surgery and spectacles could restore vision for over half of those with severe visual loss.
Area of Science:
- Ophthalmology and Public Health
- Epidemiology of Visual Impairment
- Regional Eye Care Planning
Background:
- A regional prevention of blindness program necessitates understanding the current burden of eye disease.
- Southeast Turkey's demographic shifts and healthcare needs require specific epidemiological data.
- Baseline data are crucial for evaluating the impact of future public health interventions.
Purpose of the Study:
- To conduct a population-based survey of blindness and eye disease in Diyarbakir and Mardin provinces, southeast Turkey.
- To assess the need for basic ophthalmic services in both rural and urban communities.
- To establish baseline data for the evaluation of a regional prevention of blindness program.
Main Methods:
- Stratified cluster random sampling of 8,571 individuals.
- Assessment of visual acuity, identification of eye diseases, and estimation of service needs.
- Age-standardization for comparison with other populations, such as the European Economic Community (EEC).
Main Results:
- Prevalence of visual impairment (worse than 6/18) was 1.9%; blindness (worse than 3/60) was 0.4%.
- Age-standardized blindness prevalence was 8 times higher than in the EEC.
- Leading causes of blindness: cataract (50%), corneal opacity (15%), glaucoma (12%). Causes of low vision: cataract (52%), refractive errors (26%). Acute inflammatory trachoma affected an estimated 25,900 people.
Conclusions:
- Over half of severe visual loss in the region is potentially remediable via cataract surgery and aphakic correction with spectacles.
- Significant need for ophthalmic services: 26,600 requiring cataract surgery, 4,400 needing eyelid surgery for trachoma, and 28,600 needing spectacles.
- A projected four-fold increase in blindness is expected with population aging unless ophthalmic services are improved concurrently with general development.
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