title: The relationship between irritable bowel syndrome, functional dyspepsia, chronic fatigue and overactive bladder syndrome: a controlled study 6 years after acute gastrointestinal infection.
abstract: BACKGROUND
  To investigate in a cohort with previous gastrointestinal infection and a control group the prevalence of overactive bladder syndrome (OAB), and how it was associated with three other functional disorders; irritable bowel syndrome (IBS), functional dyspepsia (FD) and chronic fatigue (CF).
  
  
  METHODS
  Controlled historic cohort study including 724 individuals with laboratory confirmed giardiasis six years earlier, and 847 controls matched by gender and age. Prevalence and odds ratios (OR) with 95 % confidence intervals (CI) were calculated.
  
  
  RESULTS
  The prevalence of OAB was 18.7 % (134/716) in the exposed group and 13.6 % (113/833) in the control group (p = 0.007). The association between OAB and IBS was strong in the control group (OR: 2.42; 95 % CI: 1.45 to 4.04), but insignificant in the Giardia exposed (OR: 1.29; 95 % CI: 0.88 to 1.88). The association between OAB and FD was weak in both groups. CF was strongly associated with OAB (OR: 2.73; 95 % CI: 1.85 to 4.02 in the exposed and OR: 2.79; 95 % CI: 1.69 to 4.62 in the controls), and this association remained when comorbid conditions were excluded.
  
  
  CONCLUSIONS
  Sporadic IBS was associated with increased risk of OAB, whereas post-infectious IBS was not. An apparent association between OAB and previous Giardia infection can be ascribed to comorbid functional disorders.
authors.affiliation: Research Unit for General Practice, Uni Research Health, Bergen, Norway. persson.robert@gmail.com.
authors.forename: Robert
authors.initials: R
authors.lastname: Persson
authors.affiliation: Research Unit for General Practice, Uni Research Health, Bergen, Norway. awensaas@online.no.
authors.forename: Knut-Arne
authors.initials: KA
authors.lastname: Wensaas
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway. kurt.hanevik@med.uib.no.
authors.forename: Kurt
authors.initials: K
authors.lastname: Hanevik
authors.affiliation: Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway. geir.egil.eide@helse-bergen.no.|Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway. geir.egil.eide@helse-bergen.no.
authors.forename: Geir Egil
authors.initials: GE
authors.lastname: Eide
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway. nina.langeland@mofa.uib.no.|Department of Medicine, Haukeland University Hospital, Bergen, Norway. nina.langeland@mofa.uib.no.
authors.forename: Nina
authors.initials: N
authors.lastname: Langeland
authors.affiliation: Research Unit for General Practice, Uni Research Health, Bergen, Norway. guri.rortveit@isf.uib.no.|Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway. guri.rortveit@isf.uib.no.
authors.forename: Guri
authors.initials: G
authors.lastname: Rortveit
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D004196:Disease Outbreaks; D004415:Dyspepsia / Q000150:complications*; D015673:Fatigue Syndrome, Chronic / Q000150:complications*; D005260:Female; D005500:Follow-Up Studies; D005873:Giardiasis / Q000150:complications* / Q000453:epidemiology; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D053201:Urinary Bladder, Overactive / Q000453:epidemiology / Q000209:etiology*; D055815:Young Adult