The effects of sleep and light at night on melatonin in adolescents

Abstract

OBJECTIVE: The circadian hormone melatonin has wide-reaching effects on human physiology. In adolescents, the impact of nighttime light exposure and other modifiable behavioral factors on melatonin levels is poorly understood. DESIGN: We cross-sectionally examined the influence of nighttime behaviors on melatonin levels in 100 adolescents (average age: 15.7; 55 female, 45 male), who completed a self-administered questionnaire and provided a first morning urine sample to assay for urinary 6-sulfatoxymelatonin (aMT6s) levels. We used mixed-effects regression models to test for differences in aMT6s levels by categories of covariates. RESULTS: Self-reported sleep duration, ambient light levels during sleep, and use of electronics after turning off lights did not significantly predict aMT6s levels. Compared to those who reported weekend bedtimes before 11pm, urinary aMT6s levels were significantly lower among participants reporting weekend bedtimes after midnight (52.5 vs. 38.0 ng/mg creatinine, Ptrend=0.007). Sleep interruption also appeared to be significantly associated with lower urinary aMT6s levels, but only if lights were turned on during sleep interruption (43.0 ng/mg creatinine for participants with sleep interruption but not turning lights on, vs. 24.6 ng/mg creatinine for participants reporting that they turned on the light when their sleep was interrupted Pdifference=0.032). CONCLUSIONS: Our study suggests that self-reported sleeprelated behaviors have little to no effect on adolescent circadian systems, though larger studies are needed to confirm our findings.

Serum Melatonin with Respect to Mental Health (Anxiety & Depression) Status of First Year M.B.B.S Students

“…The results of the present study shows that there is no significant difference in melatonin secretion in the students with late bedtime. Similar type of result was that, the night-time behaviours of adolescents, did not impact urinary melatonin levels [33].…”

“…Also increased prevalence of anxiety and depression is seen in females as compared to males. Literature studies have shown increased melatonin levels in females than in males [23,24,25]. Though other studies of melatonin in adolescents did not find significant sex differences [26,27] .…”

The effects of illuminance and correlated colour temperature on daytime melatonin levels in undergraduates with sub-syndromal SAD

“…All participants were required to follow a consistent sleep-wake schedule (bedtimes no later than 23:00 and wake times no later than 08:00) during the week before the study day to the end of the study, to maintain their daytime serum melatonin circadian rhythm. [42][43][44] The sleep-wake schedule execution and physical condition of each participant were tracked every day. Light treatment was performed in a closed space and regular examinations were conducted during the study to ensure that none of the participants had closed their eyes (except for blinking), so that their status could meet the requirements of the study.…”

Does ambient light at night reduce total melatonin production?

“…Dear Editor, It was with great interest that we read the recent study by Hersh et al 1 on the effects of sleep and light at night on melatonin in adolescents. Of particular interest was their focus on electronic use after "lights out".…”