An Epidemiological Study of Glaucoma Prevalence and Spectrum of Glaucoma Severity

Abstract

 

Purpose:

 

To determine the distribution of glaucoma severity in a community care setting in the US and to determine the agreement between patients' glaucoma stage from data collected by ophthalmologists and glaucoma stage determined by a validated glaucoma staging system based on VFL, visual acuity, and other ophthalmologic factors.

 

Methods:

 

Patients were sampled from 43 ophthalmology practices, chosen based on participation in ophthalmology registries. Patient data on factors such as demographics, risk factors, visual field test results, and IOP lowering medication use during the ophthalmologist visit were collected via case report forms. Sites enrolled 50 consecutive patients with glaucoma or ocular hypertension. Ophthalmologists staged patients using a modified Bascom Palmer scale (Mills RP, et al. Am J Ophthalmol 2006). Of the 2,296 patients sampled, visual field testing was performed between February and June 2007 on 2,092 OD and 2,097 OS. If visual field testing could not be performed the eye was considered stage 5. Kappa statistics measured agreement between physician staging and published scale.

 

Results:

 

Mean age of the sample was 68.7 years (SD=14.3); the majority were women (58.4%). Physicians staged patients less severely than the GSS, and agreement between physician stage and GSS was fair; OD Kappa: 0.5163 (95% CI: 0.4724 - 0.5603), OS Kappa: 0.4820 (95% CI: 0.4384 - 0.5256).  

 

Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • visual fields