Incidence and progression of myopia in young adults

Abstract

Purpose : Myopia primarily develops during childhood however a sizeable number of individuals continue to experience myopia progression into adulthood with some individuals only becoming myopic as adults. This study aims to describe the natural history of myopia progression in adults using anonymised electronic medical records (EMR) from Irish optometric practices.

Methods : Refractive error change was determined among patients with multiple eye exam visits during the period 1st January 2003 to 31st December 2022. Myopia was defined as a spherical equivalent refraction (SER) of ≤ -0.50 D in the right eye with high myopia defined as ≤ -6.00 D. Myopic patients aged 18 to 39 years inclusive attending more than one eye exam with an interval of at least 11 months between visits were included in the analysis. Myopia progression rates were annualised by dividing the difference in SER between visits by the time in years elapsed between those visits. Myopia progression was assessed using linear mixed models (LLM) with age, sex and baseline SER as fixed effect covariates and random intercept terms for subject. The proportion of patients with unstable myopia (progression < -0.25 D/year or < -0.50 D/year) was determined.

Results : EMR data were extracted from 40 optometry practices across Ireland, and included data from 1,176,167 practice visits by 434,738 unique patients. Of these unique patients, 13,185 (female n = 8,567, 65%) met the inclusion criteria. Analysis with LLM revealed younger age (0.006 D/year, p < 0.001) and more myopic SER at baseline (0.011 D/year, p < 0.001) to be predictive of faster myopic progression. The number of patients with non-stable myopia (progression < -0.25 D/year) was highest in younger patients (23.4%) and in high myopes (19.9%)[Figure 1]. A significant number of adult high myopes (8.0%) exhibited fast myopic progression, greater than 0.5D/year.

Conclusions : A majority of patients in this age group have stable myopia although younger patients and more myopic patients are more likely to progress and may benefit from myopia management.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Figure 1: Proportion of patients with non-stable myopia (progression < -0.25 D/year or < -0.50 D/year) given various baseline refractive states