Association of Initial Optical Coherence Tomography Angiography Vessel Density Loss With Faster Visual Field Loss in Glaucoma.

Importance: Rapid vessel density loss during an initial follow-up period may be associated with the rates of visual field loss over time.
Objectives: To evaluate the association between the rate of vessel density loss during initial follow-up and the rate of visual field loss during an extended follow-up period in patients suspected of having glaucoma and patients with primary open-angle glaucoma.
Design, Setting, and Participants: This retrospective cohort study assessed 124 eyes (86 with primary open-angle glaucoma and 38 suspected of having glaucoma) of 82 patients who were followed up at a tertiary glaucoma center for a mean of 4.0 years (95% CI, 3.9-4.1 years) from January 1, 2015, to February 29, 2020. Data analysis for the current study was undertaken in March 2021.
Main Outcomes and Measures: The rate of vessel density loss was derived from macular whole-image vessel density values from 3 optical coherence tomography angiography scans early during the study. The rate of visual field loss was calculated from visual field mean deviation during the entire follow-up period after the first optical coherence tomography angiography visit. Linear mixed-effects models were used to estimate rates of change.
Results: A total of 124 eyes from 82 patients (mean [SD] age, 69.2 [10.9] years; 41 female [50.0%] and 41 male [50.0%]; and 20 African American [24.4%], 10 Asian [12.2%], 50 White [61.0%], and 2 other race or ethnicity [2.4%]) were assessed. The annual rate of vessel density change was -0.80% (95% CI, -0.88% to -0.72%) during a mean initial follow-up of 2.1 years (95% CI, 1.9-2.3 years). Eyes with annual rates of vessel density loss of -0.75% or greater (n = 62) were categorized as fast progressors, and eyes with annual rates of less than -0.75% (n = 62) were categorized as slow progressors. The annual rate of visual field loss was -0.15 dB (95% CI, -0.29 to -0.01 dB) for the slow optical coherence tomography angiography progressors and -0.43 dB (95% CI, -0.58 to -0.29 dB) for the fast optical coherence tomography angiography progressors (difference, -0.28 dB; 95% CI, -0.48 to -0.08 dB; P = .006). The fast optical coherence tomography angiography progressor group was associated with the faster overall rate of visual field loss in a multivariable model after adjusting to include concurrent visual field mean deviation rate (-0.17 dB; 95% CI, -0.33 to -0.01 dB; P = .04).
Conclusions and Relevance: The findings of this cohort study suggest that faster vessel density loss during an initial follow-up period was associated with faster concurrent and subsequent rates of visual field loss during an extended period.