title: Prevalence and associated factors of functional gastrointestinal disorders and bowel habits in Chinese adolescents: a school-based study.
abstract: OBJECTIVE
  In the present study, we explored the prevalence rates and association factors of functional gastrointestinal disorders and the most common modes and frequencies of bowel habit among a cohort of Chinese adolescents.
  
  
  METHODS
  A stratified, randomized study based on cross-sectional data was performed using cluster sampling, which recruited 3671 students in Shanghai, China. All of the students were requested to complete a questionnaire.
  
  
  RESULTS
  Overall, 88.05% ± 0.28% of students had a bowel movement frequency of between 1 of 2 times per day and once every 2 days. Female students were found to have a lower bowel frequency than boys (P < 0.01). The prevalence of irritable bowel syndrome (IBS), functional constipation, and functional diarrhea were 19.89%, 24.93%, and 5.42%, respectively. Certain factors adjusted for age and sex were significantly associated with IBS (P < 0.05), including gastrointestinal tract infection (odds ratio [OR] 2.26), abuse of analgesics (OR 1.25), air swallowing to terminate hiccups (OR 1.28), fatigue (OR 1.15), and depression (OR 1.36). Other factors that were adjusted for age and sex, such as fried food (OR 1.68), air swallowing to terminate hiccups (OR 1.21), anxiety (OR 1.12), and depression (OR 1.57), were significantly associated with the presence of functional constipation (P < 0.05).
  
  
  CONCLUSIONS
  : Our findings suggest that normal bowel frequency among Chinese urban adolescents may be defined as between 1 or 2 bowel movements per day and once every 2 days. IBS, functional constipation, and diarrhea are common disorders among this adolescent group.
authors.affiliation: Department of Gastroenterology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China. hq.zhou@yahoo.com.cn
authors.forename: Huiqing
authors.initials: H
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Yao
authors.forename: Guang-Yu
authors.initials: GY
authors.lastname: Cheng
authors.forename: Yan-Ping
authors.initials: YP
authors.lastname: Chen
authors.forename: Ding-Guo
authors.initials: DG
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D002648:Child; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D003248:Constipation / Q000453:epidemiology / Q000209:etiology / Q000523:psychology; D003430:Cross-Sectional Studies; D003672:Defecation; D003863:Depression / Q000503:physiopathology; D003967:Diarrhea / Q000453:epidemiology / Q000209:etiology / Q000523:psychology; D005247:Feeding Behavior; D005260:Female; D005767:Gastrointestinal Diseases / Q000453:epidemiology* / Q000209:etiology* / Q000523:psychology; D041981:Gastrointestinal Tract / Q000502:physiology / Q000503:physiopathology*; D006306:Health Surveys; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000453:epidemiology / Q000209:etiology / Q000523:psychology; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012727:Sex Characteristics; D014504:Urban Health