A 2-week program combining personalized sleep scheduling with morning bright-light glasses and evening blue light–blocking glasses may be associated with earlier circadian timing and longer weeknight sleep duration in adolescents with late sleep patterns but could have limited effect on circadian alignment.
In the trial, researchers randomly assigned 86 adolescents aged 16 to 19 years to the Sleeping Late Teens Program or sleep-monitoring control. Among the participants, 80 completed baseline procedures, and 76 completed postintervention assessments. Eligible participants were enrolled in 11th or 12th grade in a traditional, synchronous, primarily in-person high school and reported habitual weekend sleep onset later than 1:00 AM.
The intervention included one collaborative problem-solving session of less than 1 hour, followed by 2 weeks of a personalized sleep schedule designed to move sleep and wake times earlier. The participants assigned to the intervention group were asked to wear morning bright-light glasses for 60 minutes on waking during days 1 and 2, then for 30 minutes on waking during days 3 to 14. They were also asked to wear amber-tinted blue light–blocking glasses for 2 hours prior to their scheduled bedtime.
The primary outcomes were weeknight circadian timing measured by salivary dim-light melatonin onset; weeknight sleep duration measured by actigraphy, and circadian alignment defined as the interval between dim-light melatonin onset and midsleep. Analyses were intention-to-treat and used linear mixed-effects models, with sex at birth included as a covariate. The researchers used Bonferroni correction for the primary outcomes.
Following the intervention period, dim-light melatonin onset shifted 36 minutes earlier in the intervention group and 9 minutes later in controls, for a 45-minute relative advance. Weeknight sleep duration increased by 47 minutes in the intervention group compared with the control group. Mean weekday sleep duration increased from 6.48 to 7.27 hours in the intervention group and remained similar in controls, at 6.52 hours at baseline and 6.54 hours at follow-up.
There were no significant differences in the third primary outcome between the two groups. Dim-light melatonin onset to midsleep alignment shortened by 18 minutes in the intervention group and lengthened by 8 minutes in controls, but the between-group difference wasn't found to reach statistical significance.
Exploratory outcomes suggested broader changes in sleep timing and regularity. The participants in the intervention group shifted sleep onset about 1 hour earlier on weekdays and weekends, shifted wake times about 20 minutes earlier on weekdays and 2 hours earlier on weekends, and had reduced daily and weekday-to-weekend sleep irregularity. Sleep continuity didn't change in either group. Morning alertness ratings increased in the intervention group and decreased in controls.
Circadian phase moved earlier in the intervention group while moving later in controls, and weekday sleep duration increased while weekend sleep duration decreased. The researchers suggested that the decline in weekend sleep may have reflected earlier weekend wake times and potentially reduced need for weekend catch-up sleep. Across the week, the intervention yielded an average 16-minute increase in sleep duration per night.
Adherence varied by component. The participants used morning bright-light glasses on 79% of mornings, followed earlier stable wake times on 76% of mornings, wore blue light–blocking glasses on 68% of nights, and followed earlier bedtimes on 63% of nights. The participants rated the program favorably, with mean ratings of 7.6 of 10 for liking the program overall and 7.1 of 10 for having an easy time following the intervention.
The researchers reported no adverse events. However, they noted several limitations, including the short 2-week duration that didn't assess longer-term outcomes, lack of follow-up testing to assess maintenance, reliance on dim-light melatonin onset without dim-light melatonin offset to assess circadian alignment, and no explicit intervention component addressing daytime naps. The sample predominantly involved White and non-Hispanic participants, which may have limited generalizability. Monetary incentives, daily text messages to promote adherence, and differences in time spent with study staff also may have contributed to group differences.
The researchers also noted practical limitations for clinical translation, including the cost of wearable light devices and the possibility that continued use may be needed for long-term effects. They indicated that lower-cost strategies, including natural daylight, screen filters, and school or home lighting changes, may warrant further study.
“In this randomized clinical trial, a 2-week sleep program including morning bright-light glasses and evening blue light–blocking glasses shifted circadian timing earlier and extended weeknight sleep duration,” wrote lead study author Delainey L. Wescott, PhD, of the Department of Psychiatry at the University of Pittsburgh School of Medicine, and colleagues.
The study was supported by the National Institute on Drug Abuse and the National Heart, Lung, and Blood Institute. Co-study author Meredith L. Wallace, PhD, reported receiving personal fees for the role as senior associate editor of Sleep Health and additional personal fees from Noctem Health and Health Rhythms outside the submitted work. Co-study author Daniel J. Buysse, MD, reported consulting fees from Sleep Number, Synchronicity Pharma, and Google Health outside the submitted work; reported involvement in the development of several sleep-related questionnaires, including the Pittsburgh Sleep Quality Index, its PTSD addendum, the Brief Pittsburgh Sleep Quality Index, the Daytime Insomnia Symptoms Scale, the Pittsburgh Sleep Diary, the Insomnia Symptom Questionnaire, and RU SATED, for which he receives a portion of licensing fees through the University of Pittsburgh; reported co-authorship of the Consensus Sleep Diary, with licensing fees distributed through an agreement between the University of Pittsburgh and Ryerson University. Senior study author Brant P. Hasler, PhD, reported receiving grant funding from the National Institute on Drug Abuse during the conduct of the study. The study authors reported no other conflicts of interest.
Source: JAMA Pediatrics