Glaucoma Progression Detection Time Using OCT and OCTA in African and European Descendants.

PURPOSE

To assess time to detection of glaucoma progression using optical coherence tomography (OCT) and OCT angiography (OCTA) among individuals of African descent (AD) and European descent (ED).

DESIGN

Retrospective cohort study.

SUBJECTS

AD and ED glaucoma subjects from the Diagnostic Innovations in Glaucoma Study (DIGS) with ≥2-year and 4 visits of OCT and OCTA imaging.

METHODS

Linear mixed effects model-derived OCT and OCTA variability estimates were used to simulate longitudinal data by race. We performed 2 assessments on the time to detect trend-based glaucoma progression (ie, significantly negative OCT and OCTA slope): in assessment I (racial comparison within modality), "standardized simulation" assumed the same, standardized OCT and OCTA baseline and slopes for both races, whereas "real-world simulation" used real-world racial cohort-derived baseline and slopes. In assessment II (modality comparison within race), simulation was performed with real-world racial cohort-derived OCT and OCTA baseline and quartile (p25/p50/p75) change rates. The required time and 2- and 5-year rates of progression detection using OCT and OCTA in individual races was evaluated.

RESULTS

We included 48 AD eyes (31 subjects) and 120 ED eyes (77 subjects), of which baseline age and VF severity were similar. In assessment I standardized simulation, with assumed OCT and OCTA slopes of -0.5 to -2.0 units/year, the time to OCT progression detection ranged from 2.4 to 5.2 years in ED and 2.6 to 5.6 years in AD (difference: <0.4 years). For OCTA, the time to progression ranged from 2.3 to 4.9 years in ED and 2.4 to 5.0 years in AD (difference: <0.2 years). In real-world simulation, with OCT slopes of -0.38 and -0.52 µm/y, the time to OCT progression was 7.0 and 5.1 years for AD and ED, respectively. For OCTA, with slopes of -0.56%/y and -0.77%/y, the time to progression was 4.3 and 3.9 years for AD and ED, respectively. In assessment II, compared with OCT, OCTA showed shorter time to progression detection (difference: 0.4-2.6 years) and higher progression rates in both races.

CONCLUSIONS

Using computer simulation, there was no racial difference in OCT and OCTA time to progression detection between AD and ED. Moreover, OCTA showed shorter time and higher rate of progression detection than OCT in both races. Although its clinical importance remains to be confirmed, our findings suggest an ancillary role of OCTA to OCT when capturing glaucoma progression across races.