Abstract
Purpose :
Glaucoma affects more than 60 million people globally. It is the second most common cause of visual impairment, but nearly half of patients are undiagnosed. Night vision problems are commonly reported by patients with glaucoma, but few studies have formally investigated their prevalence or severity. The study assessed the extent to which patients with glaucoma have subjective difficulties with dark adaptation (DA) and correlated the reported difficulties with severity of disease, specifically visual field loss.
Methods :
Cross-sectional survey of 201 patients with primary open angle glaucoma, pigmentary glaucoma and control patients presenting in an outpatient subspecialty glaucoma clinic. Patients were graded on the Hodapp-Parrish-Anderson (HPA) Glaucoma Grading Scale. 12-item survey was utilized that asked questions related to dark adaptation and night vision problems. The response format was Likert-type (severe, moderate, mild, or no difficulty). Linear regression, multivariate analysis, and stepwise multiple regression were performed using SPSS® (Version 22.0, IBM Corp.).
Results :
Dark adaptation (DA) survey score correlated with the mean deviation of the visual field (n=68, R2 =0.066, p<0.035). Univariate analysis failed to find an association with the pattern standard deviation, visual field index, age, gender, race, lens status, or family history. Multivariate analysis found that cup-to-disc ratio combined with DA score were the best predictors of visual field loss (adjusted R2=0.156; p<0.001). DA survey score increases with Hodapp-Parrish-Anderson stage (p<0.001). A stepwise multiple regression model incorporating as predictors the DA survey score, family history of glaucoma, cup-to-disc ratio, and cup-to-disc ratio difference had a sensitivity of 95%, specificity of 97%, and positive predictive value of 98.5% for the presence of glaucoma (adjusted R2=0.744; p<0.001).
Conclusions :
Glaucoma is not a symptomless disease. Night vision problems are common in patients with glaucoma, and symptom severity correlates with visual field loss. Screening for dark adaptation symptoms may help identify subjects with visual field loss from glaucoma. Future work will validate the survey in a larger population, and determine the extent to which other diseases with and without visual field loss impact symptom severity.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.