Prevalence of Cataract in an Older Population in India: The India Study of Age-related Eye Disease

Purpose—To describe the prevalence of cataract in older people in 2 areas of north and south India. Design—Population-based, cross-sectional study. Participants—Randomly sampled villages were enumerated to identify people aged ≥60 years. Of 7518 enumerated people, 78% participated in a hospital-based ophthalmic examination. Methods—The examination included visual acuity measurement, dilatation, and anterior and posterior segment examination. Digital images of the lens were taken and graded by type and severity of opacity using the Lens Opacity Classification System III (LOCS III). Main Outcome Measures—Ageand gender-standardized prevalence of cataract and 95% confidence intervals (CIs). We defined type of cataract based on the LOCS III grade in the worse eye of: ≥4 for nuclear cataract, ≥3 for cortical cataract, and ≥2 for posterior subcapsular cataract (PSC). Any unoperated cataract was based on these criteria or ungradable dense opacities. Any cataract was defined as any unoperated or operated cataract. Results—The prevalence of unoperated cataract in people aged ≥60 was 58% in north India (95% CI, 56–60) and 53% (95% CI, 51–55) in south India (P = 0.01). Nuclear cataract was the © 2011 Elsevier Inc. ⁎Correspondence: Astrid Fletcher, PhD, Department of Epidemiology & Population Health, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK [email protected]. This document was posted here by permission of the publisher. At the time of deposit, it included all changes made during peer review, copyediting, and publishing. The U.S. National Library of Medicine is responsible for all links within the document and for incorporating any publisher-supplied amendments or retractions issued subsequently. The published journal article, guaranteed to be such by Elsevier, is available for free, on ScienceDirect. Manuscript no. 2009-1174. Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article. Supported by the Wellcome Trust UK Grant 073300. Sponsored document from Ophthalmology Published as: Ophthalmology. 2011 February ; 118(2-19): 272–278.e2.