Prevelence and causes of visual impairment and blindness in older adults in an area of India with a high cataract surgical rate

Ophthalmic Epidemiol. 2010 Aug;17(4):185-95. doi: 10.3109/09286586.2010.483751.


Background: The cataract surgical rate (CSR) in Gujarat, India is reported to be above 10,000 per million population. This study was conducted to investigate the prevalence and causes of vision impairment/blindness among older adults in a high CSR area.

Methods: Geographically defined cluster sampling was used in randomly selecting persons >or= 50 years of age in Navsari district. Subjects in 35 study clusters were enumerated and invited for measurement of presenting and best-corrected visual acuity and an ocular examination. The principal cause was identified for eyes with presenting visual acuity < 20/32.

Results: A total of 5158 eligible persons were enumerated and 4738 (91.9%) examined. Prevalence of presenting visual impairment < 20/63 to 20/200 in the better eye was 29.3% (95% confidence interval [CI]: 27.5-31.2) and 13.5% (95% CI: 12.0-14.9) with best correction. The prevalence of presenting bilateral blindness (< 20/200) was 6.9% (95% CI: 5.7-8.1), and 3.1% (95% CI: 2.5-3.7) with best correction. Presenting and best-corrected blindness were both associated with older age and illiteracy; gender and rural/urban residence were not significant. Cataract in one or both eyes was the main cause of bilateral blindness (82.6%), followed by retinal disorders (8.9%). Cataract (50.3%) and refractive error (35.4%) were the main causes in eyes with vision acuity < 20/63 to 20/200, and refractive error (86.6%) in eyes with acuity < 20/32 to 20/63.

Conclusions: Visual impairment and blindness is a significant problem among the elderly in Gujarat. Despite a reportedly high CSR, cataract remains the predominant cause of blindness.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aged
  • Blindness / epidemiology*
  • Blindness / etiology
  • Cataract / complications
  • Cataract / epidemiology*
  • Cataract Extraction / statistics & numerical data*
  • Female
  • Humans
  • India / epidemiology
  • Male
  • Middle Aged
  • Prevalence
  • Refractive Errors / complications
  • Refractive Errors / epidemiology
  • Retinal Diseases / complications
  • Retinal Diseases / epidemiology
  • Vision, Low / epidemiology*
  • Vision, Low / etiology
  • Visual Acuity
  • Visually Impaired Persons / statistics & numerical data*