A patient’s risk of myopia onset can be influenced by various things, including parental myopia, female gender, longer axial length, reduced outdoor time, increased near work time and accommodative insufficiency. Since cycloplegia isn’t readily available for most medical practitioners outside of eyecare offices, assessment of spherical equivalent (SE) refraction—commonly used in myopia studies—has limited applicability for other care providers. A recent cohort study observed the performance of SE obtained using non-cycloplegic methods as a predictor of myopia, which would be more accessible across the board for patient assessment.
Researchers included 1,022 children aged six to 10 years from two elementary schools in Wenzhou, China. The participants were evaluated at baseline and annual follow-up appointments for three years. The doctors performed non-cycloplegic refraction, ocular biometry and accommodation measurements. A total of 830 of the students were non-myopic at baseline. Two years into the study, roughly one in four schoolchildren developed myopia (27.6%). Non-cycloplegic SE and positive relative accommodation (PRA) were the top two predictors for myopia onset, which may help children’s care providers calculate patient risk.
The following factors were shown to be associated with myopia onset, many of which we have seen in previous studies: female gender, better study grades, less hyperopic SE, worse visual acuity, longer near work time and lower magnitude of PRA.
Baseline axial length was also observed to be a strong predictor, as it has been before; however, due to its large variability and tendency to be influenced by other factors, it’s best to use both axial length and non-cycloplegic SE as complementary predictors.
“This report provides an evaluation of the predictors of myopia onset for key stakeholders (parents, optometrists, clinicians and professionals at the primary eye-care level and clinical practice),” the authors explained in their paper on the study. “Individuals at higher risk of myopia onset could be considered for closer monitoring, or targeted interventions that prevent or delay myopia onset.”
Wong YL, Yuan Y, Su B, et al. Prediction of myopia onset with refractive error measured using non-cycloplegic subjective refraction: the weprom study. BMJ Open Ophthalmol. June 9, 2021. [Epub ahead of print].