Alteration of retinal layers in healthy subjects over 60 years of age until nonagenarians

Purpose: To assess alterations of retinal layers in healthy subjects over 60 years old.

Methods: Retinal layers of 160 healthy subjects (aged 60-100 years) without any retinal pathology were imaged using spectral domain optical coherence tomography. Mean thickness of retinal nerve fiber layer, ganglion cell/inner plexiform layer (GCLIPL), inner nuclear layer, outer plexiform layer/outer nuclear layer, photoreceptor complex (PR) and retinal thickness (RT) were measured in a 3.45 mm grid. Correlations between age and layers were estimated and linear regression equations were calculated. Different age-groups (60-69, 70-79, 80-89 years and nonagenarians, each group with 40 participants) were compared.

Results: Significant age-thickness correlations were observed for GCLIPL (P<0.001, r=-0.394), PR (P<0.001, r=-0.370) and RT (P<0.001, r=-0.290). A comparison between age groups 60-69 years and nonagenarians showed no significant thickness alteration of retinal nerve fiber layer (21.80±2.18 μm vs 22.82±2.97 μm, P=0.163), inner nuclear layer (37.23±3.02 μm vs 36.01±3.24 μm, P=0.07) and outer plexiform layer/outer nuclear layer (104.95±6.56 μm vs 104.23±7.59 μm, P=0.567), while GCLIPL (83.35±7.35 μm vs 74.38±9.09 μm), PR (83.03±3.31 μm vs 79.34±2.09 μm) and RT (330.64±12.63 μm vs 316.83±18.35 μm) showed a significant decrease (P<0.001 for all).

Conclusion: Our study provides normative data of alterations of retinal layers for persons aged 60 years to nonagenarians and indicates a continuous decrease of RT, PR, and GCLIPL. This data may be useful for clinical trials investigating macular diseases in older patients.