The Association Between Visual Acuity and Functional Limitations: Findings from a Nationally Representative Population Survey

PURPOSE: To determine the independent effect of visual acuity on individual activities of daily living (ADL), instrumental activities of daily living (IADL) and mobility. METHODS: Cross-sectional survey on a sample representing the Finnish population aged 55 years and above. Of the 3392 eligible people, 3185 (93.9%) were interviewed, 2870 (84.6%) attended a comprehensive health examination, and 2781 (82.0%) had distance visual acuity (VA) assessed. A home interview included assessment of ADL, IADL and mobility, demographic variables and chronic conditions. Mobility measurements and binocular VA were assessed during the examination. RESULTS: Prevalence of ADL, IADL, and mobility limitations increased with decreasing VA (p<0.001). Visually impaired persons (VA< or =0.25) had ADL disabilities four times more likely than those with good VA (VA> or =0.8) after adjustment for socio-demographic and behavioral factors, and chronic conditions (OR 4.36, 95%CI 2.44-7.78). Limitations in IADL and measured mobility were five times as likely (OR 4.82, 95%CI 2.38-9.76 and OR 5.37, 95%CI 2.44-7.78, respectively), and self-reported mobility limitations were three times as likely (OR 3.07, 95%CI 1.67-9.63) as in persons with good VA. CONCLUSIONS: Decreased VA is strongly associated with functional limitations, and even a slight decrease in VA was found to be associated with limitations in functioning.