Threat to fixation at diagnosis and lifetime risk of visual impairment in open-angle glaucoma.

PURPOSE

To investigate whether threat to fixation (TTF) at diagnosis increases the risk of central vision loss and glaucoma blindness.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 309 patients (309 eyes) with glaucoma were followed up until death; 203 patients (65.7%) had primary open-angle glaucoma, and 106 patients (34.2%) had exfoliation glaucoma.

METHODS

Study eyes were divided into 2 groups according to TTF in the first glaucomatous visual field: (1) eyes with TTF, defined as visual field loss (VFL) including ≥1 of the 4 innermost points depressed at P -6.00 decibels (dB) versus 95.7% with MD <-20.00 dB. Univariate analysis demonstrated that eyes with TTF at presentation compared with eyes without TTF became blind more often (56/182 [30.8%] vs. 22/127 [17.3%]; P = 0.008) and faster (mean time from diagnosis to blindness, 84.6±50.7 vs. 126.7±51.4 months; P < 0.002). However, in multivariate analysis, TTF was not an independent risk factor for VA <0.3 (odds ratio, 1.43; 95% confidence interval, 0.75-2.74) or blindness (odds ratio, 1.03; 95% confidence interval, 0.52-2.01). With regard to patient survival time, there were no differences between eyes with TTF and eyes without TTF after adjusting for disparities in disease severity at presentation (P = 0.934).

CONCLUSIONS

Including TTF in the assessment of risk for glaucoma blindness did not add any important information when the stage of VFL was taken into account.