Glaucoma in large-scale population-based epidemiology: a questionnaire-based proxy

Abstract

PurposeTo improve upon self-reported glaucoma status in population-based cohorts by developing a questionnaire-based proxy incorporating self-reported status in conjunction with glaucoma-specific visual complaints.MethodsA vision specific questionnaire, including questions from the National Eye Institute Visual Functioning Questionnaire-25 (NEI-VFQ-25) was administered to 79,866 Lifelines participants, a population-based cohort study in the Northern Netherlands. We compared NEI-VFQ-25 responses between ‘definite’ glaucoma cases (n = 90; self-reported surgical cases) and an age- and gender-matched subset of controls (n = 1,800) to uncover glaucoma-specific visual complaints, using a case–control logistic regression. We defined ‘probable glaucoma’ as both self-reported disease status and visual complaints, and ‘possible glaucoma’ as either. To evaluate the resulting proxy, we determined age-stratified glaucoma prevalences in the remaining cohort and compared the result to the literature.ResultsPer unit increase in the vision subscales (range 0–100) distance, peripheral and low luminance, we observed significantly increased odds of definite glaucoma (2% [P = 0.03], 4% [P = 1.2 × 10−8] and 2% [P = 0.02], respectively); the associated area under the curve was 0.73. We identified 300 probable and 3,015 (1,434 by self-report) possible glaucoma cases. Standardised prevalences of definite, probable and possible glaucoma for 55+ were 0.4%, 1.1% and 7.3%, respectively. For self-reported glaucoma (combining definite, probable and possible by self-report), this was 5.2%.ConclusionsThe combination of self-reported glaucoma status and visual complaints can be used to capture glaucoma cases in population-based settings. The resulting prevalence of combined definite and probable glaucoma (1.5%) appears to be more consistent with previous reports than the prevalence estimate of 5.2% based only on self-report.