Factors associated with visual field or structure progression occurring first in a prospective study on patients with untreated open-angle glaucoma with normal intraocular pressure

Background/objectives: To identify factors associated with disc/retina deterioration in stereo fundus photographs preceding that of the visual field (VF), as determined with a Humphrey Field Analyzer (HFA) (Structure First deterioration) and factors associated with the latter preceding the former (Field First deterioration) in open-angle glaucoma (OAG) with lower normal intraocular pressure (IOP).

Subjects/methods: Prospective cohort study. Ninety eyes of 90 patients with OAG and a baseline IOP < 15 mmHg participated in a 5-year prospective study without treatment. IOP measurements and HFA 24-2 Swedish Interactive Test Algorithm Standard tests were performed every 3 months, and fundus photographs were obtained every 6 months. VF deterioration was determined by Guided Progression Analysis and deterioration of disc/retina was determined on stereophotographs by an independent committee. A multivariable Cox proportional hazard model was used to identify factors associated with Structure First deterioration, and with Field First deterioration.

Results: The average baseline age and mean deviation were 53.9 ± 9.8 years and -2.8 ± 2.8 dB, respectively. During the 5-year follow-up, the probability of Field First deterioration was 49% ± 6.6% (standard error) and that of Structure First deterioration was 33% ± 6.4% (P = 0.062, log-rank test). Disc hemorrhage (DH) prior to the event (P = 0.006) was associated with Structure First deterioration, and older age was associated with Field First deterioration (P = 0.040).

Conclusions: In OAG eyes with lower normal IOP, DH was significantly associated with Structure First deterioration, and age was significantly associated with Field First deterioration.