The association between visual acuity and functional limitations: findings from a nationally representative...

To determine the independent effect of visual acuity on individual activities of daily living (ADL), instrumental activities of daily living (IADL) and mobility.

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.

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.

Decreased VA is strongly associated with functional limitations, and even a slight decrease in VA was found to be associated with limitations in functioning.