Diagnosed open-angle glaucoma in screened versus unscreened subjects-a long-term age cohort study

Abstract

Purpose To investigate and compare the cumulative incidence of diagnosed open-angle glaucoma (OAG) in an age cohort of elderly people, of which one group was screened. Methods Cohort study comprising all 856 individuals born in 1915 and living in the municipality of Skellefteå in 1981. A randomly selected subgroup of the cohort (40%) was repeatedly screened, and suspected OAG cases were followed until 2002 for the development of OAG. Medical records were collected and analysed for OAG. The numbers of OAG cases were compared between the screened group and the remaining part of the cohort (the unscreened group). Results The cohort consisted of 339 screened and 517 unscreened persons. Before 1981, there were six known cases of OAG in the screened group and nine cases in the unscreened group. During the follow-up from 1981 to 2002, there were 33 new cases in the screened group and 31 new cases of OAG in the unscreened group. The incidence of diagnosed OAG in women was higher in the screened group than in the unscreened group, incidence rate ratio = 1.94 (p = 0.035). In contrast, the cumulative incidence of diagnosed OAG in men was similar in the two groups (p = 0.58). For the whole population, there was no significant difference (p = 0.053). Conclusion In this population with a high prevalence of PEX and increased risk for glaucoma, there was a non-significant difference between the screened and unscreened groups regarding the proportion of diagnosed OAG. The failure to reach significance may be due to the limited sample size. OAG was diagnosed twice as often among women in the screened group than in the unscreened group. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.