Association of choroidal thickness with intermediate age-related macular degeneration in a Japanese population

Abstract Purpose To determine the relationship of choroidal thickness with the early stages of age-related macular degeneration (AMD) and their disease features in a Japanese population. Design Cross-sectional survey Participants A total of 1293 Japanese persons aged 65–86 years residing in the Saku area who underwent eye screening as part of the Japan Public Health Center-based Prospective Study. Methods Comprehensive ophthalmic assessment included fundus photography, measurement of intraocular pressure, and determination of refractive status. Optical coherence tomography with enhanced depth imaging mode was performed and subfoveal choroidal thickness was assessed. Multinomial logistic regression models were used to assess the relationships of choroidal thickness with the early stages of AMD, namely early AMD and intermediate AMD, and their disease features, after adjustment for potential confounders. Main Outcome Measures Relationship of choroidal thickness with early AMD, intermediate AMD, and their disease features. Results Of the 1293 potential participants, 901 (mean age 73.2 years) had choroidal thickness data, fundus photographs of sufficient quality, and no concomitant retinal disease (including 5 late AMD cases). Mean choroidal thickness was 246.1 μm, and 15.1% had early AMD and 9.0% had intermediate AMD. After adjustment for age, sex, and refractive status, choroidal thickness was positively associated with the presence of intermediate AMD (for each 1-SD micrometer increase, OR: 1.43, 95% CI: 1.13–1.81), whereas no significant association was found with the presence of early AMD. Among intermediate AMD features, choroidal thickness was positively associated with the presence of AMD pigmentary abnormalities (associated with at least medium drusen; for each 1-SD micrometer increase, OR: 2.21, 95% CI: 1.42–3.42), whereas no significant association was found with the presence of large drusen alone. In addition, among large drusen subtypes, choroidal thickness was positively associated with the presence of pachydrusen (for each 1-SD micrometer increase, OR: 1.53, 95% CI: 1.10–2.13). Furthermore, exploratory analysis revealed that choroidal thickness was positively associated with the presence of non-AMD pigmentary abnormalities (for each 1-SD micrometer increase, OR: 1.92, 95% CI: 1.31–2.182). Conclusions Choroidal thickness appears to be associated with the pathology of intermediate AMD and its features in Asians.