Distance visual acuity impairment and survival in African Americans and non-Hispanic Whites.

BACKGROUND Regional studies conducted in the United States have shown associations between visual impairment and shorter survival in non-Hispanic Whites. OBJECTIVE To examine associations between visual impairment and mortality in a nationally representative sample of African Americans and non-Hispanic Whites residing in the United States. DESIGN Mortality linkage with participants from the 1974-1975 National Health and Nutrition Examination Augmentation Survey was performed by the National Center for Health Statistics in 1992. SUBJECTS Complete data were available on 245 African Americans and 2571 non-Hispanic Whites. METHODS Uncorrected binocular distance visual acuity was assessed using Sloan letter charts. Usual-corrected visual acuity was then obtained with participants wearing glasses or contact lenses, if any. Analytical methods included Cox regression models with adjustment for sample weights and design effects as well as age, gender, smoking status, and self-rated health. RESULTS Multivariate survival analyses found a significant interaction between race and visual impairment status; consequently, race-specific analyses were performed. There were no significant associations between uncorrected binocular visual acuity impairment (20/50 or worse) and all-cause mortality or cancer mortality. There was no significant association between impaired uncorrected acuity and cardiovascular disease mortality in African Americans (Hazard Ratio=0.67, 95% CI: 0.35-1.26), but this association was significant in non-Hispanic Whites (Hazard Ratio=1.21, 95% CI: 1.01-1.45). In multivariate models, within race groups, impaired usual-corrected visual acuity was not associated with an increased risk of all-cause mortality or mortality due to cancer or cardiovascular disease. CONCLUSIONS Uncorrected and usual-corrected binocular distance visual impairment is not associated with all-cause mortality or cancer mortality. Cardiovascular disease mortality risk may be slightly higher in non-Hispanic Whites with uncorrected visual acuity impairment.