Determinants of visual functions in patients with early and intermediate age-related macular degeneration: the PEONY...

Although decline in visual functions have been reported in eyes with non-advanced age-related macular degeneration (AMD), it is not known if visual functions in these eyes are influenced by structural changes on optical coherence tomography (OCT). We investigated the association between known OCT changes with photopic and scotopic visual functions.

Participants aged 55 years or over with early or intermediate AMD in at least 1 eye, and controls with healthy maculae and were included. Associations between visual functions and retinal structural changes were investigated using linear regression and survival analysis.

We found that the presence of refractile drusen and nascent geographic atrophy (nGA) and were associated with poorer best-corrected visual acuity (BCVA), low luminance VA (LLVA), and increased low luminance deficit (LLD) (P < 0.05). In survival analysis, eyes with thicker subfoveal choroidal thickness (SFCT) had a higher hazard rate of rod intercept, suggesting a decreased rod-intercept time (RIT). Eyes with nGA, drusen, refractile drusen, subretinal drusenoid deposits (SDD) have a significantly lower hazard rate of rod intercept (i.e. increased RIT, P < 0.05). Among them, thinner SFCT, drusen, and SDD were identified as independent factors associated with an increased RIT in the final multivariable model (P < 0.05).

Given the associations between visual functions with outer retinal layers thickness and presence of established precursors of progression to advanced AMD, our findings serve as a strong foundation for future investigations into the relationships between retinal phenotypes and functional changes.