Blue Blocking Filters and Sleep Scores in Myopic Children

Abstract

Objective: To determine whether wearing high blue-blocking spectacle filters for two hours before bedtime improves sleep in myopic children and young adolescents already treated with low-dose atropine.

Methods: A prospective, double-masked, parallel-group controlled trial was carried out at a tertiary eye hospital in Bengaluru, India, between 2023 and 2024. Children aged 8 to 13 years using atropine 0.01% eye drops were allocated alternately to an orange clip-on filter blocking 99% of light between 455 and 500 nanometres or to a visually matched yellow placebo filter, worn for two hours before habitual bedtime for 12 months. Sleep was assessed at baseline, 6 and 12 months with seven-day wrist actigraphy (sleep score, 0 to 100) and the parent-reported Children's Sleep Habits Questionnaire. Between-group differences were tested with analysis of covariance adjusted for baseline values.

Results: Fifty children (25 per group) completed follow-up. At 12 months the actigraphiy sleep score had risen by a mean of 5.1 points with the blue-blocking filter and by 0.2 points with the placebo filter; the baseline-adjusted means were 89.8 and 84.5 (p<0.001). Questionnaire scores, where lower values indicate fewer sleep problems, fell by 4.8 and 3.1 points respectively; adjusted means were 45.4 and 48.5 (p<0.001). Differences were already present at 6 months. No adverse events attributable to the filters were recorded.

Conclusion: Evening blue-blocking filters added to low-dose atropine produced a sustained improvement in objective and parent-reported sleep in myopic children, supporting their use as a simple adjunct to myopia care in this age group.