title: Heart rate variability in the irritable bowel syndrome: a review of the literature.
abstract: BACKGROUND
  Patients with irritable bowel syndrome (IBS) often present with disturbances of bowel habits (diarrhea, constipation) and abdominal pain/discomfort that are modulated by the autonomic nerve system (ANS). In this narrative review, we analyzed studies that measured ANS functioning in IBS by means of heart rate variability (HRV).
  
  
  METHODS
  The PUBMED was searched with the keywords 'irritable bowel syndrome' AND ('heart rate variability' OR 'autonomic function'). We included only papers that used 'traditional' HRV indices and diagnosed IBS based on Manning or Rome criteria. Studies were sub-grouped according to methodological features of HRV analysis (24-h monitoring, short-term laboratory records, records during sleep).
  
  
  RESULTS
  Most studies reported no difference in HRV when the IBS population was compared to healthy controls. Dividing the IBS sample into subgroups--according to their predominant bowel symptoms, the severity of clinical course, the presence of depressive symptoms, or a history of abuse in the past--revealed changes in autonomic functioning.
  
  
  CONCLUSIONS
  Patients with IBS appear to experience symptoms that may be the result of changes in ANS functioning. HRV measures in clinical routine may allow assessing these changes, but further studies performed in a standardized fashion should improve the validity of HRV measures for clinical research first.
authors.affiliation: Department of Psychosomatic Medicine and Psychotherapy, University Hospital, Tübingen, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Mazurak
authors.forename: N
authors.initials: N
authors.lastname: Seredyuk
authors.forename: H
authors.initials: H
authors.lastname: Sauer
authors.forename: M
authors.initials: M
authors.lastname: Teufel
authors.forename: P
authors.initials: P
authors.lastname: Enck
mesh_terms: D001341:Autonomic Nervous System / Q000502:physiology* / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000473:pathology / Q000503:physiopathology*; D012890:Sleep / Q000502:physiology