Layer-Specific Associations of Axial Length With Retinal and Choroidal Thickness: A Nationally Representative Population-Based Study.
- 1Department of Ophthalmology, Hangil Eye Hospital, Incheon, Republic of Korea.
- 2Department of Ophthalmology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Abstract
Purpose
To characterize layer-specific, potentially non-linear associations between axial length (AL) and macular ganglion cell-inner plexiform layer (GCIPL), peripapillary retinal nerve fiber layer (RNFL), outer-retinal, and subfoveal choroidal thickness (SFCT) in a nationally representative sample of Korean adults.Methods
Cross-sectional analysis of the Korea National Health and Nutrition Examination Survey 2017-2021. Right eyes of adults ≥19 years with AL and optical coherence tomography measurements were included; eyes with major retinal or optic-nerve disease or implausible measurements were excluded. Survey-weighted spline regression tested non-linearity by a design-based nested comparison adjusted for age and sex. Ocular magnification, refractive error, and intraocular pressure were addressed in sensitivity analyses.Results
Among 9867 participants (mean age 42.6 years; AL 24.4 mm), AL was associated with all four layers (all P < 0.001). GCIPL was nonlinear (P < 0.001), steepening at longer AL, and remained so after adjustment for magnification and refractive error. The RNFL association was not robust to magnification correction: a keratometry-based correction moved the slope from -2.2 to +0.2 µm/mm (P = 0.48), and an axial-length-only factor reversed it, indicating over-correction. Outer retina was essentially preserved (≈-0.4 µm/mm), whereas SFCT showed the largest, approximately linear association (≈-31.8 µm/mm). Excluding ocular hypertension did not change the findings.Conclusions
The apparent RNFL thinning with longer AL was largely attributable to scan-circle magnification rather than tissue thinning. The other layers differed in form: a non-linear GCIPL association and a large, approximately linear choroidal reduction, with outer-retinal preservation. Interpretation should account for AL, magnification, and functional form across layers.
Related
- Patterns of cardiovascular-kidney-metabolic (CKM) syndrome stages and prevalence of lifestyle risk factors in a nationally representative iranian population study
- A US-Based Epidemiological Analysis Reveals Large Discordance Between Exclusive Dietary Recall-Based Vegetarian Status Assessment and Self-Identification in a Nationally Representative Population-Based Survey.
- Association between smoking status and choroidal thickness in the Korean population: Korea National Health and Nutrition Examination Survey 2017–2021
- Associations of non-traditional lipid-inflammatory parameters with all-cause mortality in middle-aged and older adults: Insights from two nationally representative cohorts
- Estimated cardiorespiratory fitness and incident cardiometabolic multimorbidity: findings from three nationally representative cohorts
BibTeX
@article{kim2026layerspecific,
title = {{Layer-Specific Associations of Axial Length With Retinal and Choroidal Thickness: A Nationally Representative Population-Based Study.}},
author = {Min-Ji Kim and Dah Hyun Ryu and Mingui Kong},
journal = {Investigative ophthalmology \& visual science},
year = {2026},
month = oct,
doi = {10.1167/iovs.67.12.26},
url = {https://europepmc.org/article/MED/42872946},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Layer-Specific Associations of Axial Length With Retinal and Choroidal Thickness: A Nationally Representative Population-Based Study.
AU - Min-Ji Kim
AU - Dah Hyun Ryu
AU - Mingui Kong
PY - 2026
DA - 2026/10/01
JO - Investigative ophthalmology & visual science
DO - 10.1167/iovs.67.12.26
UR - https://europepmc.org/article/MED/42872946
AB - Purpose To characterize layer-specific, potentially non-linear associations between axial length (AL) and macular ganglion cell-inner plexiform layer (GCIPL), peripapillary retinal nerve fiber layer (RNFL), outer-retinal, and subfoveal choroidal thickness (SFCT) in a nationally representative sample of Korean adults.Methods Cross-sectional analysis of the Korea National Health and Nutrition Examination Survey 2017-2021. Right eyes of adults ≥19 years with AL and optical coherence tomography measurements were included; eyes with major retinal or optic-nerve disease or implausible measurements were excluded. Survey-weighted spline regression tested non-linearity by a design-based nested comparison adjusted for age and sex. Ocular magnification, refractive error, and intraocular pressure were addressed in sensitivity analyses.Results Among 9867 participants (mean age 42.6 years; AL 24.4 mm), AL was associated with all four layers (all P < 0.001). GCIPL was nonlinear (P < 0.001), steepening at longer AL, and remained so after adjustment for magnification and refractive error. The RNFL association was not robust to magnification correction: a keratometry-based correction moved the slope from -2.2 to +0.2 µm/mm (P = 0.48), and an axial-length-only factor reversed it, indicating over-correction. Outer retina was essentially preserved (≈-0.4 µm/mm), whereas SFCT showed the largest, approximately linear association (≈-31.8 µm/mm). Excluding ocular hypertension did not change the findings.Conclusions The apparent RNFL thinning with longer AL was largely attributable to scan-circle magnification rather than tissue thinning. The other layers differed in form: a non-linear GCIPL association and a large, approximately linear choroidal reduction, with outer-retinal preservation. Interpretation should account for AL, magnification, and functional form across layers.
SN - 0146-0404
SN - 1552-5783
ER -