Repeated low-level red-light therapy shows potential for myopia prevention

The use of repeated low-level red-light (RLRL) intervention helps prevent myopia in children with premyopia, as reported in a study.

This 12-month, parallel-group, school-based randomized clinical trial was conducted in 10 primary schools in Shanghai, China. In total, 139 children with premyopia (cycloplegic spherical equivalence refraction [SER], −0.50 to 0.50 dioptre [D] in the more myopic eye and having at least one parent with SER ≤−3.00 D) were enrolled.

The children were randomly assigned to the intervention group (mean age 8.3 years, 51.1 percent boys) or the control group (mean age 8.3 years, 48.9 percent boys). Those in the intervention group underwent RLRL therapy twice a day, 5 days per week, with each session lasting 3 minutes. On the other hand, those in the control group did not receive RLRL therapy and were only instructed to continue usual activities.

At 12 months, the primary outcome of the incidence of myopia (defined as SER ≤−0.50 D) was documented in 49 of 120 children in the intervention group and 68 of 111 in the control group (40.8 percent vs 61.3 percent; relative reduction in incidence, 33.4 percent). Among children in the intervention group who did not have treatment interruption secondary to the COVID-19 pandemic, the incidence rate of myopia was 28.1 percent (nine of 32), a relative reduction of 54.1 percent in incidence.

Compared with the control group, the RLRL intervention led to a significant reduction in the myopic shifts in terms of axial length (mean, 0.30 vs 0.47 mm; difference, 0.17 mm, 95 percent confidence interval [CI], 0.11–0.23) and SER (mean, –0.35 vs –0.76 D; difference, –0.41 D, 95 percent CI, –0.56 to –0.26).

Results of optical coherence tomography scans among children in the intervention group showed no visual acuity or structural damage.