Progression of visual field loss in untreated glaucoma patients and glaucoma suspects in St. Lucia, West Indies

Abstract

Purpose: A 1986-1987 survey found 8.8% prevalence of open-angle glaucoma in the black population of St. Lucia, West Indies. This follow-up study assessed visual field loss progression in untreated glaucoma patients and glaucoma suspects 10 years later.

Design: Cohort study.

Methods: Subjects were 205 glaucoma patients and suspects; 1987 data included age, sex, visual acuity, and visual fields measured by automated threshold perimetry (Humphrey C 30-2 test), and 1997 data included intraocular pressure, visual acuity, and visual fields measured by the same test. Exclusion criteria included field unreliability, field improvement due to vision improvement, nonglaucomatous vision deterioration, glaucoma treatment since 1988, and scoring of a visual field as end stage in 1987. Visual fields were scored by algorithms for the Advanced Glaucoma Intervention Study (AGIS) and Collaborative Initial Glaucoma Treatment Study (CIGTS).

Results: By AGIS criteria, 55% of 146 right eyes and 52% of 141 left eyes showed progression of visual field loss. In linear regressions, progression severity was unassociated with sex, intraocular pressure, or baseline visual field score, but was positively associated with age (P <.001, right; P =.002, left). The cumulative probability of reaching end stage in 10 years in at least one eye was approximately 16% by AGIS criteria. By CIGTS criteria, 73% of 146 right eyes and 72% of 141 left eyes progressed.

Conclusions: These data provide a unique opportunity to study progression of untreated glaucoma. The percentage of eyes showing visual field loss progression and the percentage reaching end stage were considerably higher than in studies of visual field progression in treated eyes.