Association between outdoor activity and peripapillary choroidal thickness in school-aged children: a 1-year observational study

Abstract

Abstract This study investigated the relationship between changes in choroidal thickness (CT) and environmental factors, given that CT alterations may predict myopia progression in school-aged children. Tokyo-based elementary schoolchildren were assessed from July 2023 to July 2024. Students who transferred, received atropine treatment, or required a lid speculum were excluded. Measurements included the spherical equivalent, axial length, and CT in foveal-centered regions—central (C0), inner (C1), and outer (C2)—and ocular total higher order aberrations (THOAs) (φ = 4 mm). Multiple regression analyses examined the associations between C0CT, C1CT, and C2CT and sex, body mass index, outdoor time, time spent on near work, reading distance, parental myopia, and ocular THOAs. Greater baseline CT was associated with greater thinning in all regions ( p  < 0.001). Longer outdoor time was associated with increased CT in the nasal quadrant of C1 and the superior quadrant of C2 ( p  < 0.05). Elevated THOAs were associated with greater CT thinning in all regions of C1 except the temporal region and the temporal quadrants of C2 ( p  < 0.05). The findings from this 1-year observational study suggested that outdoor activity contributes to regional changes in the CT, particularly in the peripapillary area between the optic disc and macula.