title: A cross-sectional study of the association between overnight call and irritable bowel syndrome in medical students.
abstract: BACKGROUND
  Shift work has been associated with irritable bowel syndrome (IBS), which includes gastrointestinal symptoms such as abdominal pain, constipation and diarrhea. Overnight call shifts also lead to a disruption of the endogenous circadian rhythm.
  
  
  OBJECTIVE
  Medical students who perform intermittent overnight call shifts will demonstrate a higher prevalence of IBS symptoms when compared with medical students who perform no overnight call shifts.
  
  
  METHODS
  First- and second-year (preclinical) medical students have no overnight call requirements, whereas third- and fourth-year medical (clerkship) students do have overnight call requirements. All medical students at the Schulich School of Medicine and Dentistry (London, Ontario) were invited to complete an anonymous, web-based survey or an identical paper copy that included demographic data, the Rome III questionnaire and the IBS-Quality of Life measure (IBS-QOL). The prevalence of IBS symptoms and quality of life secondary to those symptoms were determined.
  
  
  RESULTS
  Data were available for 247 medical students (110 preclinical students, 118 clerkship students and 19 excluded surveys). There was no significant difference in the presence of IBS between preclinical and clerkship students (21 of 110 [19.1%] versus 26 of 118 [22.0%]; P=0.58). The were no significant differences in mean (± SD) IBS-QOL score of those with IBS between preclinical (43.5±8.3) and clerkship students (45.7±13.8) (P=0.53).
  
  
  CONCLUSIONS
  Participation in overnight call was not associated with the development of IBS or a lower quality of life secondary to IBS in medical students.
authors.affiliation: Department of Medicine, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario N6A 5W9, Canada.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Wells
authors.forename: Lee
authors.initials: L
authors.lastname: Roth
authors.forename: Morgan
authors.initials: M
authors.lastname: McWilliam
authors.forename: Kim
authors.initials: K
authors.lastname: Thompson
authors.forename: Nilesh
authors.initials: N
authors.lastname: Chande
mesh_terms: D000328:Adult; D002982:Clinical Clerkship; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000453:epidemiology*; D008297:Male; D009864:Ontario / Q000453:epidemiology; D015995:Prevalence; D011788:Quality of Life; D012307:Risk Factors; D013337:Students, Medical / Q000706:statistics & numerical data; D014940:Work Schedule Tolerance; D055815:Young Adult