Eye examinations at the National Institute for Longevity Sciences--Longitudinal Study of Aging: NILS-LSA

The National Institute for Longevity Sciences--Longitudinal Study of Aging (the NILS-LSA) started in 1997, and involves many kinds of examination. The objective of this paper is to outline the eye examinations in the NILS-LSA. The eye examinations consist of checks on refractometry, visual acuity, intraocular pressure, contrast sensitivity, kinetic visual acuity, visual fields, fundus photography, and lens estimation. The subjects were 1,077 men and women aged 40-79 years who participated in the first year examination of the NILS-LSA. All subjective measurements (distant visual acuity, kinetic visual acuity, contrast sensitivity, and mean sensitivity of visual field) declined significantly from the 50s. Age-related structural changes in the lens or hypertensive and arteriosclerotic changes in retinal vessels began at least in the 40s. It is suspected that aging affects the subjective visual functions from the 50s. However, changes in the structure of eye may begin before the 40s. The data from the eye examinations of the NILS-LSA are useful to assess the aging effects on vision and to investigate the relationship between visual function and physical or psychosocial health problems among the elderly.