Positive relative accommodation is an independent risk factor for myopia onset: a prospective cohort study among chinese primary schoolchildren, the WEPrOM study.

Purpose: To identify independent risk factors for myopia onset in schoolchildren, with a focus on binocular visual function.

Methods: We conducted a school-based prospective cohort study in Wenzhou, China. Schoolchildren in grades 2 and 3 were recruited in 2014 and followed until graduation at grade 6. Myopia was defined as a spherical equivalent refraction (SER) of ≤ -0.50 diopters. The risk factors assessed included monocular uncorrected visual acuity (UCVA), axial length (AL), corneal refractive power (CR), demographic characteristics, daily activities, parental myopia, parental education level, and routine clinical binocular visual function parameters such as phoria, accommodation, and convergence-related metrics.

Results: Multivariable logistic regression analysis revealed that children with the following baseline characteristics had a significantly increased risk (OR;95% CI) of developing myopia before graduation: female sex (3.03;1.99-4.62;P<.001), having two myopic parents (2.36;1.29-4.31;P=.005), worse UCVA (19.99;2.24-178.44;P=.007), more negative SER values (0.15;0.07-0.31;P<.001), longer AL (7.28;4.30-12.31;P<.001), larger CR (2.20;1.75-2.76;P<.001), and lower magnitude of positive relative accommodation (PRA) (1.11;1.02-1.22;P=.02). Additional exploratory subgroup analyses indicated that the association between PRA and myopia incident remained consistent across various demographic characteristics (P-interaction>0.05). Receiver operating characteristic curves (AUC; 95% CI) demonstrated that PRA (0.59;0.55-0.63) exhibited predictive capability comparable to key ocular biometric parameters such as AL (0.57;0.53-0.62) and CR (0.58;0.53-0.62).

Conclusions: The current study identifies PRA as a stable, independent risk factor for myopia onset, with predictive capability comparable to key ocular biometric parameters. This finding can be utilized in future studies to enhance the accuracy of myopia prediction and assist in making informed decisions regarding myopia interventions.