Sleep Duration, Snoring Prevalence, Obesity, and Behavioral Problems in a Large Cohort of Primary School Students in Japan

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Peer Reviewed


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Scholarship Domain(s)

Scholarship of Discovery


Study Objectives: Poor or short sleep and the presence of snoring indicative of sleep-disordered breathing (SDB) have been associated with behavioral problems in school-aged children. We examined the relationship between SDB, sleep duration, obesity risk, and behavioral characteristics in Japanese elementary school students using a large-scale survey.

Methods: We conducted a cross-sectional study of children enrolled in all 46 public primary schools in Matsuyama city, Japan. The children’s parents or guardians completed a questionnaire that covered sleep habits, presence of SDB risk, and behavioral characteristics.

Results: In total, 24 296 responses were received (90% response rate). After excluding incomplete responses, we analyzed complete datasets for 17 769 children. Mean sleep duration decreased with age, as did the prevalence of pediatric SDB. We found an increased risk for the presence of SDB and short sleep among overweight/obese children. With SDB or short sleep, we observed significantly increased odds of restless behaviors, fidgety behaviors, and poor concentration in school.

Conclusions: Shorter sleep duration was associated with increased risk of obesity, and in turn, obesity increased SDB risk. Both short sleep duration and SDB risk were significantly associated with behavioral problems in school.


This is the first large-scale study to assess sleep habits, with a focus on sleep and SDB, among elementary school-aged children in Japan. We concurrently evaluated potential relationships among sleep duration, high SDB risk, presence of overweight or obesity, and behavioral patterns in school. Both short sleep and SDB adversely affected the risk for obesity and behavioral problems. Awareness campaigns to educate parents in Japan on the importance of sleep and SDB are needed.

All authors:

Naoko Sakamoto, PhD

David Gozal, MD, MBA

Dale L. Smith, PhD

Limin Yang, MD, PhD

Noriko Morimoto, MD, PhD

Hiroo Wada, MD, PhD

Kotatsu Maruyama, PhD

Ai Ikeda, PhD

Yohei Suzuki, MD

Meiho Nakayama, MD, PhD

Itsuko Horiguchi, PhD Takeshi Tanigawa, MD, PhD

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.