Can switching between different types of myopia control spectacles enhance effectiveness? Findings from a real-world study

AIMS: To investigate the effect of switching to a different type of myopia control spectacles on myopia progression. METHODS: This retrospective matched-cohort study involved 1012 children or adolescents who were prescribed myopia control spectacles. Participants were divided into two groups: the change-of-type group (n=253), who switched to a different spectacle type, and the type-maintenance group (n=759), who retained the same type, using 1:3 propensity score matching. The primary outcome was the annual rate of spherical equivalent refraction progression (D/year) compared between and within groups before and after the switch. RESULTS: The initial prescription of myopia control spectacles occurred at a mean age of 9.46±2.11 years. Subsequent prescription (renewing the same type or switching to a new type) was provided at a mean age of 10.63±2.16 years. Before switching spectacles, the change-of-type group exhibited a significantly faster myopia progression rate than the type-maintenance group (-0.66±0.40 D/year vs -0.37±0.49 D/year; p<0.001). After switching, the progression rate slowed in the change-of-type group (mean reduction 0.18 D/year, p<0.001), narrowing the intergroup difference from 0.30 D/year to 0.08 D/year (-0.48±0.61 vs -0.40±0.50 D/year; p<0.001). However, the improved effect in the change-of-type group was not sustained, with myopia progression accelerating again with prolonged use (early vs late phase, -0.33 vs -0.53 D/year, p=0.024). CONCLUSIONS: Switching to a different type of myopia control spectacle may help slow myopia progression for children exhibiting suboptimal response to their initial spectacles. However, this beneficial effect tends to wane over time with prolonged wear.