Abstract
Purpose :
To determine if the treatment effect of myopia control contact lenses (MCCL) is dependent on age, refractive error, gender and/or parental myopia in Chinese children aged 8 to 13 years.
Methods :
Two year progression of 508 Chinese children, 8 to 13 years with baseline refractive error ranging from -0.75 to -3.50D, cylinder≤ -0.75D , was estimated as the difference in spherical equivalent (SE) and axial length (AL) at 24 months from baseline. The significance of the difference between test lens (MCCL- 4 lens types combined) and control lens (SVCL) and its interaction with age, refractive error, gender and parental myopia was assessed using linear mixed model. Model based estimates were used to compute percent reduction in progression for different grades of the factors.
Results :
Progression of SE and AL with SVCL and MCCL was -0.66 ± 0.33D/0.33 ± 0.14 mm and -0.50 ± 0.38D/ 0.22 ± 0.16 mm at 1 year and -1.12±0.51D/0.58±0.27 mm and -0.87±0.58D/0.44±0.28 mm at 2 years and were significantly different between MCCL and SVCL (p ≤0.002). In addition to association with SVCL and MCCL, SE progression at year 1 and 2 was associated with baseline age (p <0.05) and with parental myopia for year 1. Similarly, AL progression at year 1 and 2 was associated with age (p =0.000) and with gender and parental myopia for year 1 and with baseline RE for year 2 (p <0.036). Although there was no significant interaction of lens type with any of these factors, with both SE and AL progression there was an improved effect with MCCL with increasing age. For example, at 1 year, efficacy increased from 17 to 34% for SE and from 28 to 40% for AL for 8 to 12 years.
Conclusions :
Progression of myopia was independently influenced by age and type of lens (either myopia control or single vision). There is no evidence of MCCL efficacy reducing with increasing age or increasing baseline RE.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.