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. 2018 May;15(5):520-530.
doi: 10.30773/pi.2018.03.17. Epub 2018 Mar 19.

Impact of Exposure to Dim Light at Night on Sleep in Female and Comparison with Male Subjects

Chul-Hyun Cho  1   2 , Ho-Kyoung Yoon  1   2 , Seung-Gul Kang  3 , Leen Kim  1   2 , Eun-Il Lee  4 , Heon-Jeong Lee  1   2   5
Affiliations

Impact of Exposure to Dim Light at Night on Sleep in Female and Comparison with Male Subjects

Chul-Hyun Cho et al. Psychiatry Investig. 2018 May.

Abstract

Objective: Light pollution has become a social and health issue. We performed an experimental study to investigate impact of dim light at night (dLAN) on sleep in female subjects, with measurement of salivary melatonin.

Methods: The 25 female subjects (Group A: 12; Group B: 13 subjects) underwent a nocturnal polysomnography (NPSG) session with no light (Night 1) followed by an NPSG session randomly assigned to two conditions (Group A: 5; Group B: 10 lux) during a whole night of sleep (Night 2). Salivary melatonin was measured before and after sleep on each night. For further investigation, the female and male subjects of our previous study were collected (48 subjects), and differences according to gender were compared.

Results: dLAN during sleep was significantly associated with decreased total sleep time (TST; F=4.818, p=0.039), sleep efficiency (SE; F=5.072, p=0.034), and Stage R latency (F=4.664, p=0.041) for female subjects, and decreased TST (F=14.971, p<0.001) and SE (F=7.687, p=0.008), and increased wake time after sleep onset (F=6.322, p=0.015) and Stage R (F=5.031, p=0.03), with a night-group interaction (F=4.579, p=0.038) for total sample. However, no significant melatonin changes. There was no significant gender difference of the impact of dLAN on sleep, showing the negative changes in the amount and quality of sleep and the increase in REM sleep in the both gender group under 10 lux condition.

Conclusion: We found a negative impact of exposure to dLAN on sleep in female as well as in merged subjects. REM sleep showed a pronounced increase under 10 lux than under 5 lux in merged subjects, suggesting the possibility of subtle influences of dLAN on REM sleep.

Keywords: Dim light at night; Melatonin; Polysomnography; REM; Sleep.

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Figures

Figure 1.
Figure 1.
Comparison of sleep parameters between Night 1 and 2 in female subjects. Significant findings (TST, SE, Stage N2, and Stage R latency) among the results of repeated measures ANOVA on sleep variables across nights and groups. Exposure to dim Artificial Light at Night during sleep was significantly associated with TST (F=4.818, p=0.039), SE (F=5.072, p=0.034), and Stage R latency (F=4.664, p=0.041). Stage N2 showed a significant night-group interaction (F=7.879, p=0.041). *p<0.05. TST: total sleep time, SE: sleep efficiency, Group A: 5 lux, Group B: 10 lux.
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References

    1. LeGates TA, Fernandez DC, Hattar S. Light as a central modulator of circadian rhythms, sleep and affect. Neuroscience. 2014;15:443–454. - PMC - PubMed
    1. Rajaratnam SM, Arendt J. Health in a 24-h society. Lancet. 2001;358:999–1005. - PubMed
    1. Czeisler CA, Johnson MP, Duffy JF, Brown EN, Ronda JM, Kronauer RE. Exposure to Bright Light and Darkness to Treat Physiologic Maladaptation to Night Work. New Engl J Med. 1990;322:1253–1259. - PubMed
    1. Parker G, Walter S. Seasonal variation in depressive disorders and suicidal deaths in New South Wales. Br J Psychiatry. 1982;140:626–632. - PubMed
    1. Vyssoki B, Kapusta ND, Praschak-Rieder N, Dorffner G, Willeit M. Direct effect of sunshine on suicide. JAMA Psychiatry. 2014;71:1231–1237. - PubMed

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