title: Irritable bowel syndrome is significantly associated with somatisation in 840 patients, which may drive bloating.
abstract: BACKGROUND
  Psychological factors may influence persistence and perceived severity of symptoms in irritable bowel syndrome (IBS). Literature suggests that somatisation is associated with IBS. However, the relationship between IBS subtype, symptoms of IBS and somatisation is unclear.
  
  
  OBJECTIVE
  To examine this issue in a large cohort of secondary care patients.
  
  
  METHODS
  Demographic and gastrointestinal (GI) symptom data were collected from 4224 adult patients via the Rome III questionnaire. Somatisation data were collected using the patient health questionnaire-12. Mean somatisation score and number of somatic symptoms were compared between IBS patients and controls with minimal GI symptoms, and between IBS subtypes using analysis of variance. Effect of level of somatisation on symptom frequency was compared according to IBS subtype using a χ(2) test.
  
  
  RESULTS
  840 patients met Rome III criteria for IBS, controls were 2137 patients with GI symptoms without IBS. Mean somatisation scores and number of somatic symptoms were higher in IBS vs. controls (P < 0.001), and in mixed stool pattern IBS (IBS-M), vs. IBS with constipation (IBS-C) or diarrhoea (IBS-D) (P < 0.001). High levels of somatisation were more prevalent in IBS-M (31.7%) vs. IBS-C (22.5%) or IBS-D (20.8%) (P = 0.003). For all IBS subtypes, high levels of somatisation were associated with a greater frequency of bloating or abdominal distension prior to logistic regression.
  
  
  CONCLUSIONS
  IBS is strongly associated with higher levels of somatisation, particularly IBS-M. Bloating may be associated with higher levels of somatisation, perhaps explaining why it can be difficult to treat.
authors.affiliation: Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK; Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK.
authors.forename: P
authors.initials: P
authors.lastname: Patel
authors.forename: P
authors.initials: P
authors.lastname: Bercik
authors.forename: D G
authors.initials: DG
authors.lastname: Morgan
authors.forename: C
authors.initials: C
authors.lastname: Bolino
authors.forename: M I
authors.initials: MI
authors.lastname: Pintos-Sanchez
authors.forename: P
authors.initials: P
authors.lastname: Moayyedi
authors.forename: A C
authors.initials: AC
authors.lastname: Ford
mesh_terms: D000328:Adult; D003248:Constipation / Q000150:complications / Q000523:psychology; D003967:Diarrhea / Q000150:complications / Q000175:diagnosis / Q000523:psychology; D005260:Female; D005414:Flatulence / Q000150:complications / Q000523:psychology*; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications* / Q000453:epidemiology / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D012959:Socioeconomic Factors; D013001:Somatoform Disorders / Q000453:epidemiology / Q000523:psychology*; D011795:Surveys and Questionnaires