Correctable visual impairment in an elderly Chinese population in Taiwan: the Shihpai Eye Study

To investigate the prevalence and risk factors of correctable visual impairment and the quality of life of persons with correctable visual impairment in a metropolitan senior population.

The study was a community-based, cross-sectional survey of vision and eye diseases among noninstitutionalized subjects aged 65 years and older in the Shihpai community of Taipei, Taiwan. The study consisted of a structured questionnaire followed by a comprehensive standardized ophthalmic examination included presenting and best corrected visual acuity, tonometry, slit lamp biomicroscopy, and direct and indirect ophthalmoscopy.

A total of 1361 subjects (response rate, 66.6%) participated in both completion of the questionnaire and ophthalmic examination. The prevalence of correctable visual impairment (presenting visual acuity in the better eye <6/12 that improved to no impairment [>/=6/12] after refractive correction) was 9.55% (95% confidence interval [CI], 7.97%-11.13%). Under multiple logistic regression analysis, older age (>/=75 years; odds ratio [OR], 2.41; 95% CI, 1.56-3.70) and nonemmetropic eyes (myopia; OR, 6.80; 95% CI, 3.77-12.77 vs. hyperopia; OR, 2.13; 95% CI, 1.29-3.51) were significantly related to correctable visual impairment. A higher level of education (OR, 0.52; 95% CI, 0.32-0.83) and wearing distance eyeglasses during the eye examination (OR, 0.23; 95% CI, 0.12-0.43) were protective factors for correctable visual impairment. Subjects with correctable visual impairment scored significantly lower in the physical functioning dimension of the SF-36 questionnaire (P < 0.001).

The results demonstrate that approximately 10% of the senior population in the Shihpai district has a correctable visual impairment. Thus, it is important to educate the public about the importance of regular examination and the possibility of improving visual acuity by wearing glasses.