Blocking Nocturnal Blue Light for Insomnia: A Randomized Controlled Trial

J Psychiatr Res. 2018 Jan;96:196-202. doi: 10.1016/j.jpsychires.2017.10.015. Epub 2017 Oct 21.

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 have health relevance given the broad use of light-emitting devices before bedtime and prevalence of insomnia. Amber lenses represent a safe, affordable, and easily implemented therapeutic intervention for insomnia symptoms.

Clinical trials registration: ClinicalTrials.gov Identifier: NCT02698800.

Keywords: Actigraphy; Behavioral intervention; Blue blocker; Insomnia; Randomized controlled trial; Sleep.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actigraphy
  • Adolescent
  • Adult
  • Aged
  • Cross-Over Studies
  • Female
  • Humans
  • Lenses
  • Male
  • Middle Aged
  • Phototherapy* / instrumentation
  • Severity of Illness Index
  • Sleep / radiation effects
  • Sleep Initiation and Maintenance Disorders / therapy*
  • Surveys and Questionnaires
  • Time Factors
  • Treatment Outcome
  • Young Adult

Associated data

  • ClinicalTrials.gov/NCT02698800