The impact of education on myopia is mainly due to alteration in axial length – results from the Gutenberg Health Study

Abstract

Purpose : Refractive error arouses as composition of different biometric parameters. To investigate the distribution of spherical equivalent and axial length in the general population and to analyze the impact of education on spherical equivalent with a focus on ocular biometric parameters.

Methods : The Gutenberg Health Study is a population-based cohort study in Mainz, Germany. Participants underwent comprehensive ophthalmologic examinations including ocular biometry, objective refraction, non-contact tonometry, and fundus imaging as part of the 5-year follow-up examination in 2012-2017.
The distributions of spherical equivalent and axial length were modeled with Gaussian mixture models. Multivariable regression analysis was performed to analyze associations between biometric parameters and educational factors. To further explore the causal effect between spherical equivalent and axial length with education, Mendelian randomization analysis was performed. In addition, an effect mediation analysis was conducted to examine the link between spherical equivalent and education with a focus on ocular biometric parameters.

Results : 9,928 study participants were included. The mean age of the study population was 57 years (interquartile range: 49; 66 years) and 42.03% were female. The distribution of spherical equivalent and axial length follows a bi-Gaussian function, which can be explained by length of education (i.e. 0-10 years vs. 11-20 years of education). Mendelian randomization revealed that the association between length of education and myopia is -0.17 diopters/year by each additional year of education (p<0.001) and 0.08 mm axial length per each additional year of education (p<0.001). In multivariable regression analysis spherical equivalent, axial length and anterior chamber depth were associated with length of education. Mediation analysis revealed that the association between spherical equivalent and education is mainly driven (77%) by alteration in axial length.

Conclusions : The distribution of axial length as well as of spherical equivalent is better represented by two subgroups of the population (bi-Gaussian), this distribution can be partially explained by length of education. The impact of education on spherical equivalent is mainly due to alteration in axial length.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.