VISUAL-ACUITY IN A POPULATION AGED 70 YEARS OR OLDER - PREVALENCE ANDCAUSES OF VISUAL IMPAIRMENT

Visual acuity and the prevalence and causes of impaired vision were st udied in an epidemiological cross-sectional population study of inhabi tants aged 70 years or older in three communities in the county of Oul u, Finland. 500 of the 560 eligible persons (89.3%) were examined. Inf ormation on visual acuity was obtaned for 476 co-operative persons (85 .0%), 59.0% had a visual acuity of 0.3-0.6 in the better eye, 10.1% (4 8 persons) had low vision and 1.9% (9 persons) were blind as categoriz ed according to the classification of visual impairment by the World H ealth Organization. Experienced visual capacity did not, however, alwa ys correspond to objective tests. Age-related maculopathy and cataract were the leading causes of visual deterioration. Age-related maculopa thy was the main cause of low vision and blindness in 4.6% of the popu lation. In 1.3% the etiology was cataract, and in 2.1% both early age- related maculopathy and cataract were present without obvious dominanc e. Cataract was often associated with other conditions. Glaucoma was c onsidered the main cause of visual deterioration in 1.5%, diabetic mac ulopathy in 0.6% and macula pucker in 0.4%. In 1.5% the visual deterio ration was due to other causes.