Age‐related changes in mesopic macular light sensitivity in healthy eyes

Abstract

AbstractPurpose: Advanced age and certain ocular pathologies are known to influence mesopic light sensitivity (MLS), but it is still unclear to what extent age can predict MLS in healthy subjects and whether there are age groups whose MLS is homogeneous. The aim was to analyse the effect of age on MLS in healthy subjects without ocular pathology.Methods: This is an observational and cross‐sectional study in 154 healthy subjects aged between 20 and 80 years (mean 43.6 ± 17.9 years) and good visual acuity. The MLS was measured with macular integrity assessment (MAIA) microperimetry at the central 10° diameter circle. MLSs at the central subfield (1° radius) and four regions (temporal, nasal, superior, inferior) of the parafoveal ring (3°–5° radius of eccentricity) were registered. The influence of age on the total mean MLS was analysed using a polynomial regression. One‐way Anova was used to compare mean MLS in each decade of age. As a result, participants were divided into three age groups (young 20–39 years, middle‐aged 40–59, and older 60–79) based on their homogenous MLS. Comparisons of MLS across age groups were performed.Results: The increase in age correlated with a decrease in the total mean MLS (r = −0.67; p = < 0.001). Mean total MLS decreased by 2.56 dB between the oldest and youngest age groups (p < 0.01). Means for MLS in the macular central subfield and in each region of the parafoveal ring (superior, temporal, nasal, inferior and overall) were significantly different in the three age groups (all (p < 0.001), with the highest sensitivities for the youngest group and the lowest for the elderly. There were not significant differences in mean MLS (total, central subfield and parafoveal regions) for men and women in each of the three age groups.Conclusions: Age predicts mean macular MLS measured by microperimetry. MLS was homogeneous in the young, middle‐aged and older age groups, being higher in young subjects and decreasing significantly every two decades of age.