Elsevier

Ophthalmology

Volume 107, Issue 7, July 2000, Pages 1267-1273
Ophthalmology

Incidence and progression of lens opacities in the Barbados Eye Studies

https://doi.org/10.1016/S0161-6420(00)00155-XGet rights and content

Abstract

Objective

To provide 4-year cumulative incidence and progression rates of age-related lens opacities in a population ≥40 years of age, which is mainly of African origin.

Design

Cohort study that reexamined surviving members of the population-based Barbados Eye Study 4 years after baseline.

Participants

Three thousand four hundred twenty-seven members of the Barbados Eye Study cohort (85% of those eligible).

Main outcome measures

The Lens Opacities Classification System II (LOCS II) was used at the slit lamp. Cumulative incidence was defined as the development of any nuclear, cortical or posterior subcapsular (PSC) opacities (LOCS II scores ≥2) among persons without that opacity type at baseline. Cumulative progression was defined by at least two-step increases in scores among persons with preexisting lens opacities.

Results

The incidence of cortical opacities was about five times greater in black than white participants (age–gender adjusted relative risk = 4.7; 95% confidence interval: 1.9–11.4). In the black population, the 4-year incidence rates were 22.2% (20.4%–24.0%) for any cortical, 9.2% (8.2%–10.4%) for any nuclear, and 3.3% (2.7%–4.0%) for any PSC opacities; rates increased greatly with age. Four-year progression rates were 12.5% for cortical, 3.6% for nuclear, and 23.0% for PSC opacities, without consistent pattern by age. Women had a greater risk of cortical and nuclear opacities (P < 0.05) than men and greater progression of nuclear opacities. The presence of PSC opacities at baseline seemed to at least double the incidence and progression rates of other opacities. In persons initially opacity free, single cortical opacities were the predominant type to develop at followup. Visual acuity loss frequently accompanied incident opacities.

Conclusions

This longitudinal study provides new population-based data on the natural history of lens opacities. Incidence and progression of opacities, especially of cortical opacities, were high. After 4 years of followup, 1 in 4 to 5 participants developed cortical opacities, 1 in 11 developed nuclear opacities, and 1 in 30 developed PSC opacities. The information obtained attests to the public health impact of age-related cataract, as well as its extent, in this and similar black populations.

Section snippets

Materials and methods

The Barbados Eye Studies, funded by the National Eye Institute, is a series of population-based investigations on the prevalence, incidence, progression, and risk factors for major causes of visual loss. The BES (1987–1992)14 measured prevalence and risk factors for major eye diseases in a random sample of Barbadian-born citizens, 40 to 84 years of age, with 84% participation. Of the 4631 BES participants completing examinations at the study site, 4314 (93%) self-reported their race as black,

Results

As described previously,15 of the 3427 persons who participated in BISED, 3193 (93%) reported their race as black, 139 (4%) as mixed, and 95 (3%) as white or other. The median age of the 3193 BISED black participants at baseline was 57 years (mean ± standard deviation = 57.6 ± 11.5 years) and 58% were women. Complete LOCS II gradings were not available for all participants because of aphakia, advanced cataract, refusal to dilate, or other reason for nongradability. As a result, 2963 had

Discussion

The Barbados Eye Studies provide the first comprehensive data on the natural history of lens opacities in a predominantly black population, as far as we know. The information obtained at baseline and at follow-up has documented the high prevalence, incidence, and progression of cataract, particularly of cortical cataract, in this population. At baseline, more than two fifths of black participants had lens changes, with cortical opacities being the most prevalent type (34%).5 An increased risk

Conclusions

A high risk of cataract in black populations, especially of cortical cataract, has been confirmed. In younger adults, cortical-only opacities were the first type noted and the most common opacities developing in persons free of lens changes at baseline. The frequent occurrence of cortical opacities may be related to the high prevalence of diabetes, highlighting the need for glycemic control. Although nuclear and PSC opacities were less common, they were often accompanied by visual loss. The

Principal investigator: M. Cristina Leske, MD, MPH

Coordinating Center

University at Stony Brook, Stony Brook, New York: M.C. Leske, MD, MPH, Barbara Nemesure, PhD, Suh-Yuh Wu, MA, Leslie Hyman, PhD, Xiaowei Li, PhD, Shu-Hong Xie, MS, Lixin Jiang, MS, Kasthuri Sarma, Barbara Springhorn, Koumudi Manthani.

Data collection center

Ministry of Health and the Environment, Bridgetown, Barbados, West Indies: Anthea M.S. Connell, FRCS, FRCOphth, Anselm Hennis, MRCP(UK), PhD, Ann Bannister, MB, BS, Muthu A. Thangaraj, MB, BS, Coreen Barrow; Patricia Basdeo, Kim Bayley,

Acknowledgements

The authors thank the Barbados Eye Studies participants and the Ministry of Health and the Environment, Barbados, West Indies, for their role in the study.

References (23)

  • S.K. West et al.

    Racial differences in lens opacities. The Salisbury Eye Evaluation (SEE) Project

    Am J Epidemiol

    (1998)
  • Cited by (0)

    Supported by grants EYO7625 and EYO7617 from the National Eye Institute, Bethesda, MD.

    1

    The authors have no commercial interests in the materials used in this study.

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