Prevalence of lens opacities in the Barbados Eye Study

Objective: To present population-based data on type and extent of age-related lens opacities in the predominantly black population of the Barbados Eye Study. Design: Prevalence study. Setting and Participants: The Barbados Eye Study included 4709 participants (84% of those eligible), who were identified from a random sample of Barbadian-born citizens aged 40 to 84 years. Data Collection: Lens gradings at the slit lamp, obtained with the use of the Lens Opacities Classification System II. Main Outcome Measure: Prevalence of posterior subcapsular, nuclear, and cortical opacities (defined as a grade greater than or equal to 2 in either eye), as well as prevalence of any lens changes (including history of previous cataract surgery and/or cataract too advanced to grade). Results: Overall, 41% of the Barbados Eye Study population had any lens changes, including 3% with aphakia or an intraocular lens. Among the population of African descent, cortical opacities (34%) were most prevalent, followed by nuclear (19%) and posterior subcapsular (4%) opacities. Prevalence of all opacity types increased with age (P<.001). Cortical and nuclear opacities were more frequent in women than men. When prevalence of a single kind of opacity was considered, 21% of participants had cortical only, 6% had nuclear only, and 0.4% had posterior subcapsular only; 13% had mixed opacities. Visual acuity loss to worse than 20/40 in the more affected eye was present in 48%, 26%, and 18% of nuclear only, posterior subcapsular only, and cortical only types, respectively, and in 53% of mixed opacities. Conclusions: The Barbados Eye Study provides the first prevalence data on different types of lens opacities in a large, predominantly black population. Whereas nuclear opacities are most common in white populations, cortical opacities were the most frequent type in the Barbados Eye Study, a finding of possible etiologic relevance. Other results highlight a higher frequency of opacities in women than men and a high prevalence of visual acuity loss in affected eyes.