title: Infection-related hospitalizations are associated with increased mortality in patients with inflammatory bowel diseases.
abstract: BACKGROUND
  Serious infections are an important side effect of immunosuppressive therapy used to treat Crohn's disease (CD) and ulcerative colitis (UC). There have been no nationally representative studies examining the spectrum of infection related hospitalizations in patients with IBD.
  
  
  METHODS
  Our study consisted of all adult CD and UC related hospitalizations from the Nationwide Inpatient Sample 2007, a national hospitalization database in the United States. We then identified all infection-related hospitalizations through codes for either the specific infections or disease processes (sepsis, pneumonia, etc.). Predictors of infections as well as the excess morbidity associated with infections were determined using multivariate regression models.
  
  
  RESULTS
  There were an estimated 67,221 hospitalizations related to infections in IBD patients, comprising 27.5% of all IBD hospitalizations. On multivariate analysis, infections were independently associated with age, co-morbidity, malnutrition, TPN, and bowel surgery. Infection-related hospitalizations had a four-fold greater mortality (OR 4.4, 95% CI 3.7-5.2). However, this varied by type of infection with the strongest effect seen for sepsis (OR 15.3, 95% CI 12.4-18.6), pneumonia (OR 3.6, 95% CI 2.9-4.5) and C. difficile (OR 3.2, 95% CI 2.6-4.0), and weaker effects for urinary infections (OR 1.4, 95%CI 1.1-1.7). Infections were also associated with an estimated 2.3 days excess hospital stay (95% CI 2.2-2.5) and $12,482 in hospitalization charges.
  
  
  CONCLUSIONS
  Infections account for significant morbidity and mortality in patients with IBD and disproportionately impact older IBD patients with greater co-morbidity. Pneumonia, sepsis and C difficile infection are associated with the greatest excess mortality risk.
authors.affiliation: Gastrointestinal Unit, Massachusetts General Hospital, Boston, MA, USA. aananthakrishnan@partners.org
authors.forename: Ashwin N
authors.initials: AN
authors.lastname: Ananthakrishnan
authors.forename: Emily L
authors.initials: EL
authors.lastname: McGinley
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D016360:Clostridioides difficile; D003015:Clostridium Infections / Q000150:complications / Q000401:mortality*; D003093:Colitis, Ulcerative / Q000150:complications / Q000401:mortality* / Q000628:therapy; D016001:Confidence Intervals; D003424:Crohn Disease / Q000150:complications / Q000401:mortality* / Q000628:therapy; D005260:Female; D017052:Hospital Mortality; D006760:Hospitalization / Q000191:economics; D006801:Humans; D007902:Length of Stay; D008297:Male; D044342:Malnutrition / Q000150:complications; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010289:Parenteral Nutrition, Total; D011014:Pneumonia / Q000150:complications / Q000401:mortality*; D012307:Risk Factors; D018805:Sepsis / Q000150:complications / Q000401:mortality*; D055815:Young Adult