Purpose: To determine the proportion of age-related ophthalmologic diseases discovered in a healthy Japanese adult population, as well as to evaluate the age-related changes in intraocular pressure (IOP) in this population during a 10-year period.
Methods: Ophthalmologic surveys were conducted in 1988 and 1998 at Tamaho-cho in Yamanashi Prefecture. The target population of the first survey was 1389 subjects over 40 years of age, and of these, 1250 subjects (473 men and 777 women) participated in the survey. Their mean age was 57.8 +/- 11.9 years. Of these 1250 subjects, 245 subjects participated in the second ophthalmologic survey in 1998. The cases of glaucoma or age-related ophthalmologic diseases developing over the intervening 10-year period were determined among the subjects who had been diagnosed with no ophthalmologic abnormalities in the 1988 survey. We also compared the IOP values of the 219 subjects who were diagnosed with no ophthalmologic abnormalities in either the 1988 or the 1998 survey.
Results: The number of cases in the 1998 survey with newly discovered ocular diseases were as follows: two cases (0.82%) of normal-tension glaucoma, two cases (0.82%) of epiretinal membrane, one case (0.41%) of age-related macular degeneration, one case (0.41%) of angle-closure glaucoma, and one case (0.41%) of branch retinal vein occlusion. The mean IOP of the 219 subjects diagnosed with no ophthalmic abnormalities in either survey was 13.88 +/- 3.04 mmHg in 1988, which declined significantly to 13.16 +/- 2.75 mmHg in 1998 (P < 0.0001).
Conclusions: The 10-year follow-up of the 245 subjects participating in both surveys showed one or two de novo cases of age-related macular degeneration, epiretinal membrane, branch retinal vein occlusion, normal-tension glaucoma, or angle-closure glaucoma. IOP was found to decline significantly with age.