Blocking nocturnal blue light for insomnia: A randomized controlled trial
Abstract
The use of light-emitting electronic devices before bedtime may contribute to or exacerbate sleep problems. Exposure to blue-wavelength light in particular from these devices may affect sleep by suppressing melatonin and causing neurophysiologic arousal. We aimed to determine if wearing amber-tinted blue light-blocking lenses before bedtime improves sleep in individuals with insomnia. Fourteen individuals (n=8 females; age ± SD 46.6 ± 11.5 y) with insomnia symptoms wore blue light-blocking amber lenses or clear placebo lenses in lightweight wraparound frames for 2 h immediately preceding bedtime for 7 consecutive nights in a randomized crossover trial (4-wk washout). Ambulatory sleep measures included the Pittsburgh Insomnia Rating Scale (PIRS) completed at the end of each intervention period, and daily post-sleep questionnaire and wrist-actigraphy. PIRS total scores, and Quality of Life, Distress, and Sleep Parameter subscales, were improved in amber vs. clear lenses condition (p-values <0.05). Reported wake-time was significantly delayed, and mean subjective total sleep time (TST), overall quality, and soundness of sleep were significantly higher (p-values <0.05) in amber vs. clear lenses condition over the 7-d intervention period. Actigraphic measures of TST only were significantly higher in amber vs. clear lenses condition (p=0.035). Wearing amber vs. clear lenses for 2-h preceding bedtime for 1 week improved sleep in individuals with insomnia symptoms. These findings…
How strong is the evidence?
Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 8 participants or records.
Read the paper
Related studies
- Temporal profiles of viral load in posterior oropharyngeal saliva samples and serum antibody responses during infection by SARS-CoV-2: an observational cohort study
- Treatment and prognostic factors for long-term outcome in patients with anti-N-Methyl-D-Aspartate (NMDA) receptor encephalitis: a cohort study
- Effectiveness of mRNA BNT162b2 COVID-19 vaccine up to 6 months in a large integrated health system in the USA: a retrospective cohort study
- Postsurgical prescriptions for opioid naive patients and association with overdose and misuse: retrospective cohort study
- Ethnic and socioeconomic differences in SARS-CoV-2 infection: prospective cohort study using UK Biobank
- Timing of high-efficacy therapy for multiple sclerosis: a retrospective observational cohort study
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.