Cataract prevalence, cataract surgical coverage and barriers to uptake of cataract surgical services in Pakistan: The Pakistan National Blindness and Visual Impairment Survey
- Zahid Jadoon (zahid{at}pico.org.pk),
- Shaheen Pravin Shah (shaheen.shah{at}lshtm.ac.uk),
- Rupert Richard Bourne (rupert.bourne{at}lshtm.ac.uk),
- Brendan Dineen,
- Mohammad A Khan,
- Clare E Gilbert,
- Allen Foster,
- Mohammad D Khan
- Pakistan Institute of Community Ophthalmology, Kyber Institute of Ophthalmic Medical Sciences, Pakistan
- International Centre for Eye Health, London School of Hygiene and Tropical Medicine, United Kingdom
- International Centre for Eye Health, London School of Hygiene and Tropical Medicine, United Kingdom
- International Centre for Eye Health, London School of Hygiene and Tropical Medicine, United Kingdom
- Pakistan Institute of Community Ophthalmology, Kyber Institute of Ophthalmic Medical Sciences, Pakistan
- International Centre for Eye Health, London School of Hygiene and Tropical Medicine, United Kingdom
- International Centre for Eye Health, London School of Hygiene and Tropical Medicine, United Kingdom
- Pakistan Institute of Community Ophthalmology, Kyber Institute of Ophthalmic Medical Sciences, Pakistan
- Published Online First 7 June 2007
Abstract
Aim: To estimate the prevalence of visual impairment and blindness due to cataract, the prevalence of aphakia/pseudophakia, the cataract surgical coverage (CSC), and to identify barriers to the uptake of cataract services among adults aged ≥30 years in Pakistan.
Methods: Probability proportional-to-size procedures were used to select a nationally representative sample of adults. Each subject underwent: interview, visual acuity measurement, autorefraction, biometry and ophthalmic examination. Those that saw < 6/12 in either eye underwent a more intensive examination procedure including: corrected visual acuity, slit lamp and dilated fundus examination. Cataract surgical coverage was calculated for different levels of visual loss by person and by eye. Individuals with <6/60 in the better eye due to cataract were interviewed regarding barriers.
Results: 16,507 adults were examined (95.5% response rate). The crude prevalence of blindness (presenting <3/60 in the better eye) due to bilateral cataract was 1.75% (95% CI: 1.55, 1.96%). 1,317 participants (633 men; 684 women) had undergone cataract surgery in one or both eyes giving a crude prevalence of 8.0% (95%CI: 7.6, 8.4%). The CSC (persons) at <3/60, <6/60 and <6/18 were 77.1%, 69.3% and 43.7% respectively. The CSC (eyes) at <3/60, <6/60 and <6/18 were 61.4%, 52.2% and 40.7% respectively. Cost of surgery (76.1%) was the main barrier to surgery.
Conclusions: There are estimated to be approximately 570,000 adults who are blind (<3/60) from cataract in Pakistan, and 3,560,000 eyes with a visual acuity of < 6/60 due to cataract. Overall, the national coverage is good but underserved populations have been identified.







