Yuichi Esaki1, Tsuyoshi Kitajima2, Kenji Obayashi3, Keigo Saeki3, Kiyoshi Fujita4, Nakao Iwata2. 1. Department of Psychiatry, Okehazama Hospital, Aichi, Japan; Department of Psychiatry, Fujita Health University School of Medicine, Aichi, Japan. Electronic address: esakiz@fujita-hu.ac.jp. 2. Department of Psychiatry, Fujita Health University School of Medicine, Aichi, Japan. 3. Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan. 4. Department of Psychiatry, Okehazama Hospital, Aichi, Japan; The Neuroscience Research Center, Aichi, Japan.
Abstract
BACKGROUND: Sleep disturbance in bipolar disorder (BD) is common and is associated with a risk for mood episode recurrence. Thus, it is important to identify factors that are related to sleep disturbance in BD. This cross-sectional study investigated the association between exposure to light at night (LAN) and sleep parameters in patients with BD. METHODS: The sleep parameters of 175 outpatients with BD were recorded using actigraphy at their homes for seven consecutive nights and were evaluated using the Insomnia Severity Index (ISI). The average LAN intensity in the bedroom during bedtime and rising time was measured using a portable photometer, and the participants were divided into two groups: "Light" (≥5 lx) and "Dark" (<5 lx). The association between LAN and sleep parameters was tested with multivariable analysis by adjusting for potential confounder such as age, gender, current smoker, mood state, day length, daytime light exposure, and sedative medications. RESULTS: After adjusting for potential confounder, the actigraphy sleep parameters showed significantly lower sleep efficiency (mean, 80.1%vs. 83.4%; p = 0.01), longer log-transformed sleep onset latency (2.9 vs. 2.6 min; p = 0.01), and greater wake after sleep onset (51.4 vs. 41.6 min; p = 0.02) in the Light group than in the Dark group. Whereas, there were no significant differences in the ISI scores between the groups. LIMITATIONS: This was a cross-sectional study; therefore, the results do not necessarily imply that LAN causes sleep disturbance. CONCLUSIONS: Reducing LAN exposure may contribute to improved sleep quality in patients with BD.
BACKGROUND: Sleep disturbance in bipolar disorder (BD) is common and is associated with a risk for mood episode recurrence. Thus, it is important to identify factors that are related to sleep disturbance in BD. This cross-sectional study investigated the association between exposure to light at night (LAN) and sleep parameters in patients with BD. METHODS: The sleep parameters of 175 outpatients with BD were recorded using actigraphy at their homes for seven consecutive nights and were evaluated using the Insomnia Severity Index (ISI). The average LAN intensity in the bedroom during bedtime and rising time was measured using a portable photometer, and the participants were divided into two groups: "Light" (≥5 lx) and "Dark" (<5 lx). The association between LAN and sleep parameters was tested with multivariable analysis by adjusting for potential confounder such as age, gender, current smoker, mood state, day length, daytime light exposure, and sedative medications. RESULTS: After adjusting for potential confounder, the actigraphy sleep parameters showed significantly lower sleep efficiency (mean, 80.1%vs. 83.4%; p = 0.01), longer log-transformed sleep onset latency (2.9 vs. 2.6 min; p = 0.01), and greater wake after sleep onset (51.4 vs. 41.6 min; p = 0.02) in the Light group than in the Dark group. Whereas, there were no significant differences in the ISI scores between the groups. LIMITATIONS: This was a cross-sectional study; therefore, the results do not necessarily imply that LAN causes sleep disturbance. CONCLUSIONS: Reducing LAN exposure may contribute to improved sleep quality in patients with BD.
Authors: Priyanka Panchal; Gabriela de Queiroz Campos; Danielle A Goldman; Randy P Auerbach; Kathleen R Merikangas; Holly A Swartz; Anjali Sankar; Hilary P Blumberg Journal: Front Psychiatry Date: 2022-05-23 Impact factor: 5.435
Authors: Randi Liset; Janne Grønli; Roger E Henriksen; Tone E G Henriksen; Roy M Nilsen; Ståle Pallesen Journal: PLoS One Date: 2022-01-28 Impact factor: 3.240