title: Incidence, clinical characteristics, and natural history of pediatric IBD in Wisconsin: a population-based epidemiological study.
abstract: BACKGROUND
  Epidemiological studies of pediatric inflammatory bowel diseases (IBD) are needed to generate etiological hypotheses and inform public policy; yet, rigorous population-based studies of the incidence and natural history of Crohn's disease (CD) and ulcerative colitis (UC) in the United States are limited.
  
  
  METHODS
  We developed a field-tested prospective system for identifying all new cases of IBD among Wisconsin children over an 8-year period (2000-2007). Subsequently, at the end of the study period, we retrospectively reconfirmed each case and characterized the clinical course of this incident cohort.
  
  
  RESULTS
  The annual incidence of IBD among Wisconsin children was 9.5 per 100,000 (6.6 per 100,000 for CD and 2.4 per 100,000 for UC). Approximately 19% of incident cases occurred in the first decade of life. Over the 8-year study period, the incidence of both CD and UC remained relatively stable. Additionally, (1) childhood IBD affected all racial groups equally, (2) over a follow-up of 4 years, 17% of patients with CD and 13% of patients with patients with UC required surgery, and (3) 85% and 40% of children with CD were treated with immunosuppressives and biologics, respectively, compared with 62% and 30% of patients with UC.
  
  
  CONCLUSIONS
  As in other North American populations, these data confirm a high incidence of pediatric-onset IBD. Importantly, in this Midwestern U.S. population, the incidence of CD and UC seems to be relatively stable over the last decade. The proportions of children requiring surgery and undergoing treatment with immunosuppressive and biological medications underscore the burden of these conditions.
authors.affiliation: Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
authors.forename: Tonya
authors.initials: T
authors.lastname: Adamiak
authors.forename: Dorota
authors.initials: D
authors.lastname: Walkiewicz-Jedrzejczak
authors.forename: Daryl
authors.initials: D
authors.lastname: Fish
authors.forename: Christopher
authors.initials: C
authors.lastname: Brown
authors.forename: Jeanne
authors.initials: J
authors.lastname: Tung
authors.forename: Khalid
authors.initials: K
authors.lastname: Khan
authors.forename: William
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authors.lastname: Faubion
authors.forename: Roger
authors.initials: R
authors.lastname: Park
authors.forename: Janice
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authors.lastname: Heikenen
authors.forename: Michael
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authors.lastname: Yaffee
authors.forename: Maria T
authors.initials: MT
authors.lastname: Rivera-Bennett
authors.forename: Marcy
authors.initials: M
authors.lastname: Wiedkamp
authors.forename: Michael
authors.initials: M
authors.lastname: Stephens
authors.forename: Richard
authors.initials: R
authors.lastname: Noel
authors.forename: Melodee
authors.initials: M
authors.lastname: Nugent
authors.forename: Justin
authors.initials: J
authors.lastname: Nebel
authors.forename: Pippa
authors.initials: P
authors.lastname: Simpson
authors.forename: Michael D
authors.initials: MD
authors.lastname: Kappelman
authors.forename: Subra
authors.initials: S
authors.lastname: Kugathasan
mesh_terms: D000293:Adolescent; D002648:Child; D003093:Colitis, Ulcerative / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D003424:Crohn Disease / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D014922:Wisconsin / Q000453:epidemiology