Longitudinal hemifield-specific macular ganglion cell complex thinning and its association with arterial stiffness in eyes without baseline glaucomatous abnormalities

PURPOSE: To characterize longitudinal hemifield-specific changes in macular ganglion cell complex (GCC) thickness in eyes without baseline glaucomatous abnormalities and to evaluate whether arterial stiffness, assessed by brachial-ankle pulse wave velocity (baPWV), is associated with the rate of GCC thinning. METHODS: In this retrospective longitudinal cohort study, 511 eyes without baseline glaucomatous abnormalities from participants in a health-checkup program were analyzed over a median follow-up of 4.75 years. Repeated macular optical coherence tomography measurements were evaluated using linear mixed-effects models. In the primary analysis, follow-up data from eyes that subsequently developed glaucoma-related events were censored at the date of first detection. Fixed effects included time, hemifield, baPWV, and their interactions, with adjustment for age, sex, axial length, baseline GCC thickness, and intraocular pressure. RESULTS: A total of 4,654 hemifield-specific observations were included in the primary analysis. GCC thinning differed significantly between hemifields, with faster thinning in the superior than in the inferior hemifield (time-by-hemifield interaction, P = 0.004). Higher baPWV was associated with faster GCC thinning after covariate adjustment (time-by-baPWV interaction, P < 0.001). The three-way interaction among time, hemifield, and baPWV was not significant (P = 0.847), and the hemifield-specific pattern remained broadly consistent across the observed baPWV range. CONCLUSION: In eyes without baseline glaucomatous abnormalities, longitudinal macular GCC thinning showed relative inferior preservation under a censored analytical framework. Higher baPWV was associated with faster overall GCC thinning, while the hemifield-specific pattern remained broadly consistent across the observed baPWV range.