Glaucoma Structural and Functional Progression in American and Korean Cohorts

Area of Science:

• Ophthalmology
• Glaucoma Research
• Population Health

Background:

• Glaucoma is a leading cause of irreversible blindness worldwide.
• Understanding ethnic variations in glaucoma progression is crucial for tailored treatment strategies.
• Previous studies have suggested differences in glaucoma prevalence and severity across ethnic groups.

Purpose of the Study:

• To compare the rates of structural and functional progression in glaucoma between American and Korean cohorts.
• To identify factors influencing glaucoma progression, including ethnicity, disease severity, and subtype.

Main Methods:

• A retrospective longitudinal study involving 313 eyes from 189 patients (glaucoma and glaucoma suspects).
• Semiannual examinations included visual field (VF) testing and spectral-domain optical coherence tomography (SD-OCT).
• Comparison of retinal nerve fiber layer (RNFL) thickness, cup-to-disc (C/D) ratios, and VF mean deviation (MD) rates, analyzing variables like ethnicity and disease subtype.

Main Results:

• The Korean cohort predominantly had normal-tension glaucoma, while the American cohort had high-tension glaucoma.
• Korean eyes exhibited faster mean RNFL thinning (-0.71 μm/year vs. -0.24 μm/year; P < 0.01) despite similar baseline VF parameters.
• No significant differences in C/D ratio or VF MD progression rates were found between cohorts, nor for any parameter in glaucoma suspect eyes.

Conclusions:

• Ethnicity significantly impacts glaucoma progression, particularly RNFL thinning.
• Baseline disease severity, disease subtype, and clinical diagnosis are critical factors to consider when comparing glaucoma progression studies.
• These findings underscore the need for ethnicity-specific considerations in glaucoma management and research.