Abstract
Purpose :
The BLINK Study was a 3-year randomized clinical trial that found +2.50 add center-distance multifocal contact lenses (MFCLs) slowed eye growth and myopia progression compared to single vision contact lenses (SVCLs) and +1.50 MFCLs. In BLINK2, all children wore +2.50 MFCLs for two years then SVCLs for one year. This analysis explores whether there was a rebound in eye growth and progression after discontinuing MFCLs.
Methods :
Myopic children (n = 248; 59% female) in the BLINK2 Study were included (mean ± SD age at start of BLINK2 = 14.9 ± 1.4 years; 11-17 years old). Axial length (AL) was measured every 6 months using optical biometry and spherical equivalent refraction (SER) was measured annually by cycloplegic autorefraction; right and left eye measurements were averaged. AL and SER were each modelled as a function of time controlling for original BLINK Study treatment group (SVCL, +1.50 MFCL, or +2.50 MFCL), baseline age, sex, race and site. Each model had two linear time predictors for the change in either AL or SER, one when wearing MFCLs (baseline to Year 2) and one when wearing SVCLs (Year 2-3).
Results :
At the start of BLINK2, mean ± SD AL and SER were 25.2 ± 0.9 mm and -3.40 ± 1.40 D, respectively. After all participants switched from MFCLs to SVCLs at Year 2, there was an increase in AL growth of 0.04 mm/year (95% CI: 0.01 to 0.06; p = 0.003) that did not depend on the original BLINK treatment assignment (p = 0.81). For SER, there was also an increase in myopia progression after switching from MFCLs to SVCLs at Year 2 of -0.16 D/year (95% CI: -0.11 to -0.21; p < 0.001) that also did not depend on the original BLINK treatment assignment (p = 0.57). There continued to be a difference in AL and SER throughout BLINK2 based on the BLINK Study treatment assignment with the original +2.50 MFCL group from BLINK having shorter eyes and lower myopia than the +1.50 MFCL and SVCL groups (both p < 0.001).
Conclusions :
While there was a statistically significant increase in eye growth and myopia progression after discontinuing MFCL wear, the increases were small and not clinically meaningful (on average, 0.04 mm/year and -0.16 D/year). These minimal increases did not depend on the length of previous MFCL wear and do not suggest a loss of treatment effect after discontinuation of MFCLs in this age group.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.