title: Somatic comorbidities of irritable bowel syndrome: a systematic analysis.
abstract: OBJECTIVE
  A large number of irritable bowel syndrome (IBS) patients are additionally afflicted with other somatic intestinal and/or extraintestinal comorbidities. The occurrence of one or more comorbidities is correlated with enhanced medical help seeking, worse prognosis, and higher rates of anxiety and depression-all resulting in a reduced quality of life. The aims of this study were, firstly, to review the literature on comorbidities of IBS and to assess gastrointestinal and extraintestinal comorbidities, and, secondly, to evaluate explanatory hypotheses and possible common pathophysiological mechanisms.
  
  
  METHODS
  We systematically reviewed the scientific literature in the past 25 years, as cited in MEDLINE.
  
  
  RESULTS
  IBS patients present with a twofold increase in somatic comorbidities compared to controls, possibly caused by common pathophysiological mechanisms. Nevertheless, to date, there has been no convincing evidence for a consolidated underlying pathophysiology or somatization. Gastrointestinal disorders, such as functional dyspepsia, gastroesophageal reflux disease, functional constipation, and anal incontinence, occur in almost half of the patients. In a broad variety of extraintestinal comorbidities, fibromyalgia, chronic fatigue syndrome, and chronic pelvic pain are best documented and appear in up to 65%.
  
  
  CONCLUSIONS
  The knowledge and structured assessment of comorbid somatic symptoms might allow to identify subgroups of IBS patients with special characteristics and lead to adaptation of the therapeutic concept.
authors.affiliation: Division of Hepatology, Gastroenterology, and Endocrinology, Department of Medicine, Charité-University Medical Center, Campus Virchow, Berlin, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Riedl
authors.forename: Marco
authors.initials: M
authors.lastname: Schmidtmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Stengel
authors.forename: Miriam
authors.initials: M
authors.lastname: Goebel
authors.forename: Anna-Sophia
authors.initials: AS
authors.lastname: Wisser
authors.forename: Burghard F
authors.initials: BF
authors.lastname: Klapp
authors.forename: Hubert
authors.initials: H
authors.lastname: Mönnikes
mesh_terms: D015897:Comorbidity; D003937:Diagnosis, Differential; D015673:Fatigue Syndrome, Chronic / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D052776:Female Urogenital Diseases / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000175:diagnosis* / Q000453:epidemiology*; D008297:Male; D052801:Male Urogenital Diseases / Q000175:diagnosis / Q000453:epidemiology; D008881:Migraine Disorders / Q000175:diagnosis / Q000453:epidemiology; D009140:Musculoskeletal Diseases / Q000175:diagnosis / Q000453:epidemiology; D010146:Pain / Q000175:diagnosis / Q000453:epidemiology; D013001:Somatoform Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology