Racial Differences in Rate of Change of Spectral-Domain Optical Coherence Tomography-Measured Minimum Rim Width and Retinal Nerve Fiber Layer Thickness.

PURPOSE

To compare race-related differences in estimated rate of change of Bruch's membrane opening-minimum rim width (BMO-MRW) and circumpapillary retinal nerve fiber layer thickness (RNFLT) in healthy, glaucoma suspect, and glaucoma eyes of individuals of European (ED) and African descent (AD).

DESIGN

Prospective cohort study.

METHODS

This study investigated rate of change of BMO-MRW and RNFLT in 124 healthy, 227 glaucoma suspect, and 177 glaucoma eyes followed for approximately 3 years and tested with optical coherence tomography every 6 months. Suspect eyes had a history of untreated intraocular pressure (IOP) ≥ 22 mm Hg or suspicion of glaucoma by optic disc photograph assessment without repeatable abnormal standard automated perimetry (SAP) results. Glaucoma eyes had repeatable abnormal SAP results (GHT ONL or PSD ≤ 5%). Mixed-effects models were used to estimate the rate of change after controlling for age, mean follow-up IOP, central corneal thickness, axial length, and BMO area.

RESULTS

A race-related difference in rate of change of global BMO-MRW but not average RNFLT in suspect eyes was observed. Rate of change of BMO-MRW was -1.82 μm/year and -2.20 μm/year in ED and AD suspect eyes, respectively (P = .03). Rate of change of RNFLT was -0.64 μm/year and -0.75 μm/year in ED and AD suspect eyes, respectively (P = .75). No race-related differences in change rate were found in healthy or glaucoma eyes.

CONCLUSION

Race is an important consideration when assessing structural change, particularly minimum rim width, in glaucoma suspect eyes. Differences in rate of structural change may help explain racial disparities in glaucoma susceptibility.