title: Meta-analysis: diagnostic medical radiation exposure in inflammatory bowel disease.
abstract: BACKGROUND
  Diagnostic imaging plays a pivotal role in the diagnosis and management of inflammatory bowel disease (IBD); however, increasing use has led to concerns about the malignant potential of ionising radiation. Several studies have demonstrated that diagnostic imaging can result in exposure to potentially harmful levels of ionising radiation in IBD patients.
  
  
  OBJECTIVE
  To determine the pooled prevalence of increased exposure and pooled odds ratio of risk factors associated with exposure to potentially harmful levels of diagnostic medical radiation.
  
  
  METHODS
  We searched Medline, EMBASE, CINHAL and reference lists of identified articles, without language restrictions in October 2011.
  
  
  RESULTS
  Six studies with 1704 participants provided data on the proportion of patients receiving potentially harmful levels of radiation defined as ≥50 milli-sieverts (mSv)-equivalent to 5 CT abdomen scans. The pooled prevalence was 8.8% (95% CI 4.4-16.8) for IBD patients and 11.1% (95% CI 5.7-20.5%) and 2% (95% CI 0.8-4.9%) for Crohn's disease and ulcerative colitis patients respectively. Five studies involving 2627 participants provided data for risk factors. IBD-related surgery and corticosteroid use were significant with pooled adjusted odds ratio of 5.4 (95% CI 2.6-11.2) and 2.4 (95% CI 1.7-3.4) respectively.
  
  
  CONCLUSIONS
  About 1 in 10 patients may be exposed to potentially harmful levels of diagnostic medical radiation. Corticosteroid use and IBD related surgery increased this risk. Strategies to reduce radiation exposure while assessing disease activity need to be considered.
authors.affiliation: Department of Gastroenterology, St George's Hospital NHS Trust, London, UK. schatu@hotmail.com
authors.forename: S
authors.initials: S
authors.lastname: Chatu
authors.forename: V
authors.initials: V
authors.lastname: Subramanian
authors.forename: R C G
authors.initials: RC
authors.lastname: Pollok
mesh_terms: D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000000981:diagnostic imaging*; D011832:Radiation Injuries / Q000209:etiology*; D011859:Radiography; D011877:Radionuclide Imaging / Q000009:adverse effects*; D011879:Radiotherapy Dosage; D012307:Risk Factors