Two-thirds of Singaporean adults have undiagnosed visually significant cataract
A new population-based study has reported that at least 66 percent of Singaporean adults have undiagnosed visually significant cataracts and that a further half of this experience considerably reduced qualities of life as a result of bilateral visual impairment.
The findings underline the importance of certain strategies to target elderly patients in helping them prevent the progression of the condition.
The current study included adults at least 40 years of age who were enrolled in the Singapore Epidemiology of Eye Diseases. The cohort represented three major ethnic groups in Singapore: Chinese (n=3,353), Malays (3,280) and Indians (n=3,400). Sampling from each ethnic group was done randomly, and according to 10-year age categories.
Each participant underwent an eye examination which included a lens photograph to diagnose cataracts. The Wisconsin Cataract Grading System was used to determine visually significant cataracts. A best-corrected visual acuity of less than 20/40 with cataract was determined as primary cause of vision impairment. The VF-11 questionnaire, as validated by the Rasch analysis, was used to evaluate visual functioning.
Of all the participants, 925 had visually-significant cataracts. Furthermore, 68.8 percent of these were unaware of their cataract statuses. The prevalence of cataracts, as standardized by age, varied across the ethnic groups. Malays were found to have higher prevalence compared with the Chinese and Indians.
Aside from the Malay ethnicity, lower educational attainment, no history of diabetes and being employed all showed an independent association with undiagnosed visually significant cataracts (all p<0.05).
Half of the participants with undiagnosed visually significant cataracts were also found to have bilateral visual impairment. Compared with the unilateral visual impairment group, the bilateral group had 24.8-percent reduced visual functioning (p<0.001).
Thus, the epidemiological assessment of eye conditions in Asian populations found that around two-thirds of adults in Singapore had undiagnosed visually significant cataracts and that a further half of them had bilateral visual impairment, which could lead to significantly reduced visual functioning.