To evaluate the effect of population screening on low vision and blindness from open-angle glaucoma.
Retrospective cohort study.
A very large population based screening for glaucoma was conducted in Malmö, Sweden, from 1992 to 1997. A total of 42 497 subjects were invited, of which 32 918 were screened and 9579 non-responders, i.e. did not participate.
The records of glaucoma patients who had visited the Department of Ophthalmology at Malmö University Hospital, from Jan 1, 1987, to Dec 31, 2017, were reviewed. Patients diagnosed at or after the screening were assessed for moderate or severe vision impairment, which we call low vision, or blindness by the WHO definition. We corrected for selection bias by creating a group of potential screening participants from a comparison group of clinical patients.
Risk ratio of the cumulative incidence for bilateral low vision or blindness caused by glaucoma in screened patients compared with the potential participants.
The cumulative incidence of blindness was 0.17% in the screened population versus 0.32% among the potential participants; and for low vision 0.25% versus 0.53%. The risk ratio (95% CI) between the two was 0.52 (0.32-0.84) for blindness and 0.46 (0.31-0.68) for low vision. There were no differences in the proportion of potential confounders between the comparison group and the non-responders.
Our results suggest that population screening may reduce bilateral low vision and blindness from glaucoma by about 50%.

Copyright © 2021. Published by Elsevier Inc.