title: Predictors for hospitalization and outpatient visits in patients with inflammatory bowel disease: results from the Swiss Inflammatory Bowel Disease Cohort Study.
abstract: OBJECTIVE
  Patients with inflammatory bowel disease (IBD) have a high resource consumption, with considerable costs for the healthcare system. In a system with sparse resources, treatment is influenced not only by clinical judgement but also by resource consumption. We aimed to determine the resource consumption of IBD patients and to identify its significant predictors.
  
  
  METHODS
  Data from the prospective Swiss Inflammatory Bowel Disease Cohort Study were analysed for the resource consumption endpoints hospitalization and outpatient consultations at enrolment [1187 patients; 41.1% ulcerative colitis (UC), 58.9% Crohn's disease (CD)] and at 1-year follow-up (794 patients). Predictors of interest were chosen through an expert panel and a review of the relevant literature. Logistic regressions were used for binary endpoints, and negative binomial regressions and zero-inflated Poisson regressions were used for count data.
  
  
  RESULTS
  For CD, fistula, use of biologics and disease activity were significant predictors for hospitalization days (all P-values <0.001); age, sex, steroid therapy and biologics were significant predictors for the number of outpatient visits (P=0.0368, 0.023, 0.0002, 0.0003, respectively). For UC, biologics, C-reactive protein, smoke quitters, age and sex were significantly predictive for hospitalization days (P=0.0167, 0.0003, 0.0003, 0.0076 and 0.0175 respectively); disease activity and immunosuppressive therapy predicted the number of outpatient visits (P=0.0009 and 0.0017, respectively). The results of multivariate regressions are shown in detail.
  
  
  CONCLUSIONS
  Several highly significant clinical predictors for resource consumption in IBD were identified that might be considered in medical decision-making. In terms of resource consumption and its predictors, CD and UC show a different behaviour.
authors.affiliation: Department of Gastroenterology and Hepatology, Kantonsspital St Gallen, St Gallen, Switzerland.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Sulz
authors.forename: Uwe
authors.initials: U
authors.lastname: Siebert
authors.forename: Marjan
authors.initials: M
authors.lastname: Arvandi
authors.forename: Raffaella M
authors.initials: RM
authors.lastname: Gothe
authors.forename: Johannes
authors.initials: J
authors.lastname: Wurm
authors.forename: Roland
authors.initials: R
authors.lastname: von Känel
authors.forename: Stephan R
authors.initials: SR
authors.lastname: Vavricka
authors.forename: Christa
authors.initials: C
authors.lastname: Meyenberger
authors.forename: Markus
authors.initials: M
authors.lastname: Sagmeister
mesh_terms: D000328:Adult; D000553:Ambulatory Care / Q000706:statistics & numerical data*; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D003424:Crohn Disease / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D005260:Female; D006295:Health Resources / Q000706:statistics & numerical data*; D006760:Hospitalization; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011446:Prospective Studies; D012017:Referral and Consultation / Q000706:statistics & numerical data; D012307:Risk Factors; D013557:Switzerland / Q000453:epidemiology; D013997:Time Factors