title: Disorders of arousal and sleep-related bruxism among Japanese adolescents: a nationwide representative survey.
abstract: OBJECTIVE
  The main objective of our study was to clarify the prevalence of disorders of arousal (confusional arousals, sleepwalking, sleep terrors) and sleep-related bruxism (teeth grinding) and their associated factors among Japanese adolescents.
  
  
  METHODS
  Our study was designed as a cross-sectional sampling survey. The targets were students attending junior and senior high schools throughout Japan. The questionnaire asked for personal data and information on lifestyle, depressive state, and sleep status including the frequency of experiencing disorders of arousal and sleep-related bruxism.
  
  
  RESULTS
  A total of 99,416 adolescents responded. The overall response rate was 63.7%, and 98,411 questionnaires were subjected to analysis. The prevalence of disorders of arousal was 7.1% (95% confidence interval [CI], 6.9-7.3%) among boys and 7.7% (95% CI, 7.5-7.9%) among girls. The prevalence of sleep-related bruxism was 2.3% (95% CI, 2.2-2.4%) among boys and 3.0% (95% CI, 2.8-3.2%) among girls. The factors associated with disorders of arousal were the grade in school, smoking habit, alcohol consumption, naptime (min), breakfast habit, participation in club activities, sleep duration, difficulty initiating sleep, nocturnal awakening, early morning awakening, subjective sleep assessment, snoring, decrease in positive feelings, and depression (all p<.001). The factors associated with sleep-related bruxism were gender, smoking habit, nocturnal awakening, snoring, early morning awakening, decrease in positive feelings, and depressive feelings (all p<.001).
  
  
  CONCLUSIONS
  If disorders of arousal or sleep-related bruxism are observed in an adolescent, his or her smoking habit, alcohol consumption, sleep status, and depressive state should be considered.
authors: Division of Public Health, Department of Social Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors: Osamu
authors: O
authors: Itani
authors: Yoshitaka
authors: Y
authors: Kaneita
authors: Maki
authors: M
authors: Ikeda
authors: Shuji
authors: S
authors: Kondo
authors: Ryuichiro
authors: R
authors: Yamamoto
authors: Yoneatsu
authors: Y
authors: Osaki
authors: Hideyuki
authors: H
authors: Kanda
authors: Kenji
authors: K
authors: Suzuki
authors: Susumu
authors: S
authors: Higuchi
authors: Takashi
authors: T
authors: Ohida
mesh_terms: D000293:Adolescent; D000428:Alcohol Drinking / Q000453:epidemiology; D044466:Asian People / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000453:epidemiology; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D020447:Parasomnias / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D020921:Sleep Arousal Disorders / Q000453:epidemiology*; D020186:Sleep Bruxism / Q000453:epidemiology*; D012907:Smoking / Q000453:epidemiology; D012913:Snoring / Q000453:epidemiology