This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this link to a friend Similar articles in this journal Similar articles in PubMed Add article to my folders Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Dunzhu, S Articles by Bassett, K L Search for Related Content PubMed PubMed Citation Articles by Dunzhu, S Articles by Bassett, K L Topic Collections Relevant Article

Blindness and eye diseases in Tibet: findings from a randomised, population based survey

¹ Tibet Autonomous Region Public Health Bureau, Tibet
² British Columbia Centre for Epidemiologic and International Ophthalmology, Canada
³ Kilimanjaro Centre for Community Ophthalmology, Kenya
⁴ Seva Foundation, Seva Canada

Correspondence to:
Correspondence to:
Dr Ken Bassett
Director, Centre for Epidemiologic and International Ophthalmology, Department of Ophthalmology, The University of British Columbia, 429-2194 Health Sciences Mall, Vancouver BC V6T 1Z3, Canada; bassett{at}chspr.ubc.ca

ABSTRACT
Background: Public health officials of the Tibet Autonomous Region (TAR) of China requested a survey of blindness, eye diseases, and eye care service utilisation to assist the development of a 10 year blindness prevention and treatment plan. The objective of the survey was to determine the prevalence of blindness and visual impairment, as well as cataract surgical coverage and surgical outcome in the TAR.

Methods: The Tibet Eye Care Assessment was a cross sectional prevalence study of three of the seven prefectures (provinces) of the TAR (Lhoka, Nakchu, and Lingzhr) selected to represent its three main environmental regions. The survey sample was selected using a random multistage cluster method. Two teams conducted the survey in a standardised fashion in each prefecture, Lhoka during May and Nakchu during June 1999, and Lingzhr during May 2000. Visual acuity, cause of vision loss, trachoma, and vitamin A deficiency were included in the clinical examination.

Results: Among the 15 900 people enumerated, 12 644 were examined for an overall response rate of 79.6%. The crude prevalence of blindness (presenting better eye visual acuity of less than 6/60) was 2.3%; age and sex adjusted blindness prevalence was 1.4% (95% CI 1.3 to 1.5). Visual impairment (better eye presenting visual acuity of 6/24 to 6/60) was found in 10.9% (95% CI 10.5 to 11.2) of the population (age and sex adjusted). Cataract was the primary cause of blindness (50.7%), followed by macular degeneration (12.7%) and corneal opacity (9.7%).

Conclusion: Blindness is a serious public health problem in Tibet, with prevalence higher than in similar studies in eastern China. As elsewhere in the world, women have an excess burden of blindness compared to men. About 75% of blindness in Tibet can be either prevented or treated. Eye care planning for Tibet must focus on cataract, particularly among women.

Keywords: blindness prevalence; Tibet; epidemiology

Relevant Article

BJO at a glance

Creig Hoyt
Br. J. Ophthalmol. 2003 87: 1437. [Extract] [Full Text] [PDF]

This article has been cited by other articles:

				N Congdon, S K Rao, K Choi, W Wang, S Lin, S Chen, L J Chen, K Liu, I C Hu, and D S C Lam Sources of patient knowledge and financing of cataract surgery in rural China: the Sanrao Study of Cataract Outcomes and Up-Take of Services (SCOUTS), Report 6 Br. J. Ophthalmol., May 1, 2008; 92(5): 604 - 608. [Abstract] [Full Text] [PDF]

				D. S. C. Lam, N. G. Congdon, S. K. Rao, H. Fan, Y. Liu, L. Zhang, X. Lin, K. Choi, Z. Zheng, W. Huang, et al. Visual Outcomes and Astigmatism After Sutureless, Manual Cataract Extraction in Rural China: Study of Cataract Outcomes and Up-Take of Services (SCOUTS) in the Caring Is Hip Project, Report 1 Arch Ophthalmol, November 1, 2007; 125(11): 1539 - 1544. [Abstract] [Full Text] [PDF]

				J. Ramke, A. Palagyi, T. Naduvilath, R. du Toit, and G. Brian Prevalence and causes of blindness and low vision in Timor-Leste Br. J. Ophthalmol., September 1, 2007; 91(9): 1117 - 1121. [Abstract] [Full Text] [PDF]

				T Y Wong, S-C Loon, and S-M Saw The epidemiology of age related eye diseases in Asia. Br. J. Ophthalmol., April 1, 2006; 90(4): 506 - 511. [Abstract] [Full Text] [PDF]

				L Xu, J Li, T Cui, A Hu, Y Zheng, Y Li, B Sun, B Ma, and J B Jonas Visual acuity in northern China in an urban and rural population: the Beijing Eye Study Br. J. Ophthalmol., September 1, 2005; 89(9): 1089 - 1093. [Abstract] [Full Text] [PDF]

				M. Muir Hygieia J Epidemiol Community Health, February 1, 2005; 59(2): 176 - 176. [Full Text] [PDF]