Myopia Progression in Children Wearing Spectacles vs. Switching to Contact Lenses

PURPOSE: To investigate myopia progression in Correction of Myopia Evaluation Trial (COMET) participants who switched to soft contact lenses (CLs) vs. remained in spectacles after the clinical trial ended. METHODS: Four hundred sixty-nine ethnically diverse, 6- to 11-year-old myopic children were randomly assigned to wear single vision lenses (SVLs) or progressive addition spectacle lenses (PALs) for 5 years as part of COMET. Afterwards they could choose another lens type, including CLs. Data in this article are from 286 participants who wore their original spectacle lenses for 6 years (n = 199) or wore CLs most or all the time between the 5- and 6-year visits (n = 87). Refractive error and axial length (AL) were measured after cycloplegia with 1% Tropicamide. The primary outcome was myopia progression between the 5- and 6-year visits. Two-year myopia progression was evaluated in a subset of 183 participants who wore the same lens type for an additional year. Myopia progression and AL were compared between the two lens groups using multiple linear regression. RESULTS: Participants in the two groups were similar with respect to age, ethnicity, myopia at 5-years, accommodation and phoria, but more girls switched to CLs than remained in spectacles (p < 0.0001). Mean (+/-SD) myopia progression was higher (p = 0.003) after 1 year in the CL group[-0.28+/- 0.33 diopter (D)] than the spectacle group (-0.14+/- 0.36 D), and remained higher after 2 years in the 2-year subset (-0.52+/- 0.46 D vs.-0.25+/- 0.39 D, p < 0.0001). Results were similar after adjustment for related factors. No significant differences in AL were found between groups after adjustment. Corneal curvature remained unchanged in both groups. CONCLUSIONS: COMET children switching from glasses to CLs experienced a small, statistically significant but clinically inconsequential increase in myopia progression.