Refractive changes in the elderly

Abstract

Purpose: Cross-sectional studies have consistently shown younger people to be less hyperopic than older people, but it is not known if this reflects a myopic shift from one generation to the next or a true age-related shift. Methods: We used data from three population surveys to study cohort phenomena and true age-related changes in refraction of elderly people in southern Sweden. Differences concerning the use of cycloplegics made us restrict comparisons between refractions in separate studies to persons aged 65 to 74 years, in whom our measurements mere considered unlikely to have been affected by accommodation. Results: An apparent increase in mean spherical equivalent as rapid as 0.6 D in 10 years was observed in our latest (and largest) cross-sectional survey The myopic shift, from one generation to the next, was limited to 0.25 D in 25 years. This discrepancy was explained by a true age-related hyperopic shift between 55 and 70, which was confirmed in a longitudinal study of over 1000 persons followed for more than 8 years. Conclusion: A true age-related hyperopic shift between 55 and 70 does indeed exist, and should not be disregarded by anyone who is prescribing spectacles or performing surgery for refractive errors. In the long run, however, a persisting secular trend towards myopia could prove even more important.