Relationship of Choroidal Thickness With Age-Related Macular Degeneration in Asians: An Asian Eye Epidemiology...

To compare the choroidal thickness (CT) of participants with various stages of age-related macular degeneration vs. normal controls through a meta-analysis of studies conducted within the Asian Eye Epidemiology Consortium.

Eight population-based studies from China, Iran, Japan, and Singapore were included. Axial length and spherical equivalent measurements and imaging with color fundus photography and spectral-domain optical coherence tomography were performed. Random-effects meta-analysis was performed to examine the association between AMD and its stages (early AMD, intermediate AMD [iAMD], neovascular AMD [nAMD], and geographic atrophy [GA]) with CT, while adjusting for age, sex, current smoking status, and axial length/spherical equivalent.

Of 17,916 participants, 13,116 participants (mean age, 62.15 ± 9.66 years) were included into the study. The mean unadjusted CT was 245.01 ± 84.04 µm (mean CT, 255.4 µm [no AMD], 263.59 µm [early AMD], 270.64 µm [iAMD], 273.32 µm [nAMD], and 156.50 µm [GA]). The presence of AMD was associated with a thicker choroid (β = 11.51; 95% confidence interval [CI], 4.10-18.92). AMD severity was also positively associated with CT. Early AMD (β = 8.75; 95% CI, 0.03-17.47), iAMD (β = 19.68; 95% CI, 13.20-26.16), and nAMD (β = 34.15; 95% CI, 6.84-61.46) were each positively associated with a thicker CT after adjusting for age, sex, smoking, and spherical equivalent. GA was not significantly associated with CT.

In a large Asian cohort, AMD is associated with a thicker choroid in early AMD, iAMD, and nAMD, but not in GA. Studying the CT will help to better characterize Asian AMD phenotypes, which may show differences compared with AMD phenotypes in Western populations.