Prevalence and causes of blindness, low vision and status of cataract in 50 years and older citizen of Qatar-a community based survey.
BACKGROUND
Rapid Assessment for the Avoidable Blindness (RAAB) was conducted in Qatar during 2009. We present the prevalence and determinants of visual disabilities and status of cataract among citizens aged 50 years and older.


METHODS
Residents of randomly selected houses and clusters participated in the survey. Opticians noted the presenting and the best corrected vision of participants from 49 clusters. Ophthalmologists examined participants with additional instruments like bio-microscope, digital camera, auto-perimeter and auto-refractor in a mobile van. World Health Organization recommended principal cause of blindness (Visual acuity [VA] < 3/60 in better eye), Severe visual impairment (SVI) (<6/60), low vision (VA < 6/18) and unilateral blindness (VA < 3/60) were designated. Persons with VA < 6/18 and cataract were interviewed to calculate coverage and barriers for cataract surgeries. Age sex adjusted prevalence of visual disabilities and their 95% Confidence Intervals (CI) were estimated.


RESULTS
We examined 2,433 (97.3%) participants. The age sex adjusted prevalence of bilateral blindness was 1.28% [95% CI 1.22-1.35], SVI (1.67%), low vision (3.66%) and unilateral blindness (3.61%) in 50 years and older population. Female and older age groups were significant risk factors of visual disabilities. Cataract and glaucoma were the main causes of visual disabilities. The coverage of cataract services was 68.2%. Believing that cataract as an aging process (25) and adequate vision in the fellow eye (15) were the reasons for delay in surgery.


CONCLUSIONS
To reduce avoidable blindness, un-operated cataract should be addressed. Primary and secondary eye care systems should be strengthened to improve the care of blinding eye diseases in Qatar.
Al Gamra
Hamad
H
Department of Ophthalmology, Hamad Medical Corporation, Doha, Qatar. halnabit@hmc.org.qa
Al Mansouri
Fatima
F
Khandekar
Rajiv
R
Elshafei
Maha
M
Al Qahtani
Omar
O
Singh
Rajvir
R
Hashim
Shakeel P
SP
Mujahed
Amjad
A
Makled
Alaa
A
Pai
Anant
A
D000368:Aged; D000369:Aged, 80 and over; D001766:Blindness / Q000453:epidemiology* / Q000209:etiology; D002386:Cataract / Q000453:epidemiology*; D004185:Disability Evaluation; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011780:Qatar / Q000453:epidemiology; D012307:Risk Factors; D015354:Vision, Low / Q000453:epidemiology* / Q000209:etiology; D014792:Visual Acuity / Q000502:physiology; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data*