Elsevier

Ophthalmology

Volume 106, Issue 3, 1 March 1999, Pages 497-504
Ophthalmology

Burden of moderate visual impairment in an urban population in southern India

https://doi.org/10.1016/S0161-6420(99)90107-0Get rights and content

Abstract

Objective

To assess the prevalence and causes of moderate visual impairment in an urban population in southern India.

Design

Population-based, cross-sectional study.

Participants

A total of 2522 (85.4% of the eligible) persons of all ages, including 1399 persons 30 years of age or older, from 24 clusters representative of the population of Hyderabad city.

Testing

The eligible subjects underwent a detailed ocular evaluation, including logarithm of the minimum angle of resolution (logMAR) visual acuity, refraction, slit-lamp biomicroscopy, applanation tonometry, gonioscopy, cataract grading, and stereoscopic dilated fundus evaluation. Automated threshold visual fields and slit-lamp and fundus photography were done when indicated by standardized criteria.

Main outcome measure

Moderate visual impairment was defined as presenting distance visual acuity less than 20/40 to 20/200 or visual field loss by predefined standardized conservative criteria in the better eye.

Results

In addition to the 1% prevalence of blindness in this sample reported earlier, moderate visual impairment was present in 303 subjects, an age-gender-adjusted prevalence of 7.2% (95% confidence interval [CI], 4.5%–9.9%; design effect, 2.7). The major cause of moderate visual impairment was refractive error (59.4%, 95% CI, 52.3%–66.5%) followed by cataract (25.3%, 95% CI, 19%–31.6%). Multivariate analysis showed that the prevalence of moderate visual impairment was significantly higher in those 40 years of age or older (odds ratio, 10.9; 95% CI, 8–15) and females (odds ratio, 1.89; 95% CI, 1.41–2.53) and lower in those belonging to the highest socioeconomic status (odds ratio, 0.27; 95% CI, 0.14–0.51). However, because of the pyramidal age distribution of the population, 38.1% of the total moderate visual impairment was present in those younger than 40 years of age. The proportion of moderate visual impairment caused by refractive error was higher in the younger than in the older age groups (P < 0.0001).

Conclusions

Projecting the results to the 26.5% urban population of India, there would be 18.4 million (95% CI, 11.5–25.2 million) persons with moderate visual impairment in urban India alone. Refractive error was the major cause of moderate visual impairment in the population studied. The absolute proportion of moderate visual impairment in those younger than 40 years of age was considerable. The eyecare policy of India, apart from dealing with blindness, should address the issue of the relatively easily treatable uncorrected refractive error as the cause of moderate visual impairment in an estimated 10.9 million persons in urban India.

Section snippets

Materials and methods

The design of APEDS is described in detail elsewhere.2, 4 This study was approved by the Ethics Committee of the L.V. Prasad Eye Institute, Hyderabad. Those aspects of the study design relevant to this article are mentioned here.

Results

Of the eligible subjects, 2522 (85.4%) were interviewed and examined between October 1996 and June 1997. The age range of these subjects was 1 month to 102 years. A total of 1399 (55.5%) were 30 years of age or older and 1347 (53.4%) were female. Two hundred thirty-two (9.2%) subjects belonged to extreme lower, 920 (36.5%) to lower, 1033 (41%) to middle, and 267 (10.6%) to the upper socioeconomic strata, while 70 (2.8%) subjects refused to give income information. A total of 1556 (61.7%)

Discussion

India is estimated to have one fourth of the world’s visually impaired population, including blindness and moderate visual impairment many fold higher than blindness.1 A comprehensive policy on eyecare is needed in India to deal with this burden of visual impairment in a long-term, sustainable manner. To develop such a policy, reliable population-based information about blindness and moderate visual impairment is needed. We have recently reported data on blindness.4 This article attempts to

References (27)

  • Census of India 1991, Andhra PradeshReligion

    (1995)
  • H.G. Scheie

    Width and pigmentation of the angle of the anterior chambera system of grading by gonioscopy

    Arch Ophthalmol

    (1957)
  • R.N. Shaffer

    Symposiumoffice management of the primary glaucomas. III. Gonioscopy, ophthalmoscopy and perimetry

    Trans Am Acad Ophthalmol Otolaryngol

    (1960)
  • Cited by (87)

    View all citing articles on Scopus

    Supported by the Hyderabad Eye Research Foundation, Hyderabad, India.

    View full text