PREVALENCE AND CAUSES OF BLINDNESS AND VISUAL IMPAIRMENT IN MONGOLIA - A SURVEY OF POPULATIONS AGED 40 YEARS AND OLDER

The survey was conducted in 3 out of the 18 administrative regions (ai maks); 4345 people aged greater than or equal to 40 years were examine d, which represented 95.7% of the proposed sample. The prevalences of blindness and low Vision in the sample were 1.5% (95% Cl, 0.8-2.3%) an d 8.1% (95% Cl, 5.5-10.7%), respectively, from which the prevalences o f blindness and law vision in the Mongolian population aged 40 years a nd older were estimated to be 1.4% and 7.7%, respectively The prevalen ce of climatic droplet keratopathy was high (ranging from 15% to 50%) in this population, which included a large number of semi-nomadic catt le breeders, and was responsible for 7.2% of the blindness and 19.3% o f the low vision. Cataract and glaucoma were the commonest blinding di sorders, each accounting for around 35% of the blindness. Trauma accou nts for a high proportion of those monocularly blind. Trachoma and xer ophthalmia were not found.