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Published on: June 13, 2025
Core body temperature changes in school-age children with circadian rhythm sleep-wake disorder
Shigemi Kimura1, Yutaka Takaoka2, Makiko Toyoura3
1Children's Rehabilitation, Sleep and Development Medical Center, Hyogo Prefectural Rehabilitation Central Hospital, 1070 Akebono-cho, Nishi-ku, Kobe, 651-2181, Japan; Division of Medical Informatics and Bioinformatics, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan.
Objective/Background:
Core body temperature (CBT) is considered a valuable marker for circadian rhythm. This study aimed to investigate the changes in CBT that are associated with the symptoms of circadian rhythm sleep-wake disorder (CRSWD) post-treatment in children.
Patients/Methods:
Twenty-eight school-age children [10 boys and 18 girls; mean age (±standard deviation), 13.68 ± 0.93 years] who were admitted to our hospital with CRSWD underwent treatment for 6-8 weeks according to the following protocol: lights-out for sleep at 21:00; phototherapy for waking at 6:00 or 7:00; light exercise everyday (eg, a 20- to 30-min walk). CBT was continuously measured for 24 h on the first day of admission and on the first day after treatment.
Results:
The mean time of sleep onset/offset (±standard deviation; in hours:minutes) 1 week before admission and 1 week after treatment were 23:53 ± 2:26/9:58 ± 2:15 and 21:17 ± 0:19/6:46 ± 0:32, respectively. The mean times of sleep onset and offset measured post-treatment were significantly earlier than those measured pre-treatment (p < 0.001). The mean CBT and mean minimum CBT during sleep were significantly lower on the first day post-treatment than on the first day of admission (p = 0.011 and p < 0.001, respectively).
Conclusions:
Symptom improvements in patients with CRSWD were associated with a decrease in CBT during sleep, suggesting that CBT may be a biomarker for improvements in CRSWD. These results help elucidate the cause of this sleep disorder.
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