A Randomized Trial of the Effect of Soft Contact Lenses on Myopia Progression in Children

Ohio State University College of Optometry, Columbus, Ohio, USA.
Investigative ophthalmology & visual science (Impact Factor: 3.4). 07/2008; 49(11):4702-6. DOI: 10.1167/iovs.08-2067
Source: PubMed


Soft contact lenses have been reported to increase the progression of myopia. The purpose of this study was to determine whether soft contact lenses affect the progression of myopia in children.
Children between the ages of 8 and 11 years with -1.00 to -6.00 D myopia and less than 1.00 D astigmatism were randomly assigned to wear soft contact lenses (n = 247) or spectacles (n = 237) for 3 years. Refractive error and corneal curvatures were measured annually by cycloplegic autorefraction, and axial length was measured annually by A-scan ultrasound. Multilevel modeling was used to compare the rate of change of refractive error, corneal curvature, and axial length between spectacle and contact lens wearers.
There was a statistically significant interaction between time and treatment for myopia progression (P = 0.002); the average rate of change was 0.06 D per year greater for contact lens wearers than spectacle wearers. After 3 years, the adjusted difference between contact lens wearers and spectacle wearers was not statistically significant (95% confidence interval [CI] = -0.46 to 0.02). There was no difference between the two treatment groups with respect to change in axial length (ANCOVA, P = 0.37) or change in the steepest corneal curvature (ANCOVA, P = 0.72).
These data provide reassurance to eye care practitioners concerned with the phenomenon of "myopic creep." Soft contact lens wear by children does not cause a clinically relevant increase in axial length, corneal curvature, or myopia relative to spectacle lens wear. (, NCT00522288.).

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