A longitudinal study of visual acuity and visual rehabilitation needs in an urban Swedish population followed from the ages of 70 to 97 years of age

Purpose: To investigate the longitudinal change in visual acuity (VA) in the oldest members of the elderly population, to estimate future numbers of people with visual impairments, and to estimate needs for and the effects of visual rehabilitation. Methods: In the Gerontological and Geriatric Population Studies in Gothenburg, Sweden (H 70), subjects underwent repeated eye examinations at the ages of 70, 82, 88, 95 and 97 years. Logistic regression analysis was used to estimate the probability of independent living as a function of distance VA at different ages. Results: Rates of normal VA (greater than or equal to 0.8) declined from 86% of the study group at age 70 to 7% of the study group at age 95 (0% at age 97). The incidence of VA less than or equal to 0.1 increased from 1.4% at age 70 to 27% (all women) at age 97. The deterioration was faster at higher ages. No statistically significant difference in best-corrected distance VA between genders was found. A substantial improvement was achieved by correcting refractive errors. There was a statistically significant correlation between distance VA and the probability of independent living at all ages except age 97. At ages 95 and 97, about 50% of the study group were able to read newspaper print with best-corrected glasses. Conclusions: The number of old people with impaired vision will increase. People aged 80 years and older should have regular eye-screening in order to preserve vision and present conditions of living. Cataract surgery and low vision rehabilitation should be offered when the subject can still benefit from it, preferably during their 80s at the latest.