Baseline accommodation and related risk factors associated with myopia progression and their interaction with treatment in COMET children

Abstract

Abstract: : Purpose: To examine baseline measurements of accommodative lag, phoria, reading distance, amount of near work, and level of myopia as risk factors for myopia progression, and their interaction with treatment, over 3 yrs in the Correction of Myopia Evaluation Trial (COMET). Methods: COMET enrolled 469 ethnically diverse children (6 – 11 yrs) with myopia between –1.25 and –4.50 D. They were randomly assigned to either progressive addition lenses (PALs) with a +2.00 addition (n = 235) or single vision lenses (SVLs; n = 234) and were followed for 3 yrs. The primary outcome measure was progression of myopia by cycloplegic autorefraction. Other measurements included accommodation with a Canon R–1, phoria, reading distance, and hrs of near work. Independent and interaction analyses were based on the mean of the 2 eyes. Results were adjusted for important covariates with multiple linear regression. Results: Children with larger accommodative lags (> 0.43D for a 33 cm target) wearing SVLs had the most progression at 3 yrs. PALs were effective in slowing progression, with statistically significant 3–yr treatment effects for children with larger lags in combination with near esophoria (PAL – SVL progression = –1.08D – (–1.72D) = 0.64D), shorter reading distances (0.44D), more hrs of near work (0.42D), or lower baseline myopia (0.48D). Statistically significant treatment effects also were observed in these groups at 1 yr and became larger from 1–3 yrs. Conclusions: The results provide some support for the COMET rationale, i.e., a role for defocus in myopia progression. In clinical practice children with poor accommodation and near esophoria often are prescribed PALs or bifocals to improve visual performance. Results of this study suggest that such children, if myopic, may have an additional benefit of slowed progression of myopia.

Keywords: myopia • clinical (human) or epidemiologic studies: risk factor assessment • refractive error development