Risk factors for previously undiagnosed primary open-angle glaucoma: the EPIC-Norfolk Eye Study

Background and aim Undiagnosed glaucoma is an invisible but important public health issue. At least half of glaucoma cases are estimated to be undiagnosed in western populations. The aim of this study is to examine risk factors for previously undiagnosed primary open-angle glaucoma (POAG). Design Cross-sectional study within the European Prospective Investigation of Cancer-Norfolk Eye Study, a large-scale cohort study in the UK. Participants 314 study participants with POAG in either eye. Methods Logistic regression was used to examine associations with previously undiagnosed POAG compared with previously diagnosed POAG. The factors examined included sociodemographic, ocular, physical and economic factors that could be barriers to eye care access. Results 217 participants had previously diagnosed POAG and 107 participants were newly diagnosed with POAG during the study. After adjusting for covariables, the factors significantly associated with previously undiagnosed POAG were: a lower pretreatment intraocular pressure (IOP) (OR 0.71/mm Hg, 95% CI 0.63 to 0.80, p<0.0001), and to have reported no problems with their eyesight (OR 0.03, 95% CI 0.01 to 0.10, p<0.0001). Conclusions The risk factors for previously undiagnosed POAG identified in this study highlight the over-reliance on IOP level in glaucoma screening and the risk of missing glaucoma among lower IOP cases. It also suggests a role in improving glaucoma awareness in the community.

Automated summary

This study identified risk factors for previously undiagnosed POAG, including lower pretreatment intraocular pressure and reporting no problems with eyesight. It suggests over-reliance on IOP level may lead to missed diagnoses of glaucoma, emphasizing the need to improve community awareness of glaucoma.