Age, Sex, and Ethnic Variations in Inner and Outer Retinal and Choroidal Thickness on Spectral-Domain Optical Coherence Tomography.

Abstract

To evaluate age, sex, and ethnic variations in inner and outer retinal and choroidal thickness and foveal pit, using spectral-domain optical coherence tomography (SD OCT). Single-center observational cross-sectional study. Ninety randomly selected, healthy individuals of white, black, and South Asian origin underwent SD OCT raster and enhanced depth imaging scan. Manual measurements of inner and outer retinal thickness and choroidal thickness up to 3mm nasal and temporal to the fovea were performed. The age, sex, and ethnic differences in these parameters were analyzed. The mean inner retinal thickness was lower by approximately 12μm in black subjects across the central retina compared to white subjects (P < .05). The central foveal thickness below the foveal pit was lower in eyes of blacks compared to South Asians (12μm, P= .035) and white subjects (18μm, P < .0001). The fovea was also significantly wider in eyes of black and South Asian subjects compared to white individuals. The inner retinal thickness decreased by 0.5μm per year of age of subjects and was thinner by 6.1μm (P < .02) in female compared to male subjects. The subfoveal choroidal thickness did not vary between ethnic groups but the temporal choroid was significantly thinner in black subjects (P < .05). The choroid showed an age-related decline in thickness of 2μm per year of age of the subjects. Interethnic differences include wider fovea, lower central foveal thickness, and thinner inner retina in eyes of black subjects compared to their white and South Asian counterparts.