title: Incidence, prevalence, and time trends of pediatric inflammatory bowel disease in Northern California, 1996 to 2006.
abstract: OBJECTIVE
  To examine the incidence and prevalence of pediatric inflammatory bowel disease (IBD) during 1996-2006 in a community-based health-care delivery system.
  
  
  METHODS
  Members of Kaiser Permanente Northern California aged 0 to 17 years with IBD were identified by use of computerized medical information with confirmation obtained through review of the medical record.
  
  
  RESULTS
  The average annual incidence of IBD per 100000 was 2.7 (95% confidence interval [CI], 2.3-3.1) for Crohn's disease (CD) and 3.2 (CI, 2.8-3.6) for ulcerative colitis (UC). During the 11-year study period, the annual incidence per 100000 increased from 2.2 to 4.3 for CD (P = .09) and from 1.8 to 4.9 for UC (P < .001). The ratio of incident CD cases to incident UC cases was 0.9 in non-Hispanic whites, 1.6 in African Americans (P = .12), 0.3 in Hispanics (P < .001) and 0.4 in Asians (P = .04). The average length of enrollment during the 11-year study period exceeded 8 years. The point prevalence on December 31, 2006, per 100000 was 12.0 for CD (CI, 9.6-14.4) and 19.5 (CI, 16.5-22.6) for UC.
  
  
  CONCLUSIONS
  In this population the incidence of UC increased significantly by 2.7-fold and CD increased 2.0-fold without reaching statistical significance. Hispanic and Asian children had development of UC more often than CD, suggesting possible etiologic differences across racial and ethnic groups.
authors.affiliation: Division of Pediatric Gastroenterology, Kaiser Permanente Northern California, Santa Clara, CA 95051, USA. oren.abramson@kp.org
authors.forename: Oren
authors.initials: O
authors.lastname: Abramson
authors.forename: Michael
authors.initials: M
authors.lastname: Durant
authors.forename: William
authors.initials: W
authors.lastname: Mow
authors.forename: Allen
authors.initials: A
authors.lastname: Finley
authors.forename: Pratima
authors.initials: P
authors.lastname: Kodali
authors.forename: Anthony
authors.initials: A
authors.lastname: Wong
authors.forename: Venessa
authors.initials: V
authors.lastname: Tavares
authors.forename: Erin
authors.initials: E
authors.lastname: McCroskey
authors.forename: Liyan
authors.initials: L
authors.lastname: Liu
authors.forename: James D
authors.initials: JD
authors.lastname: Lewis
authors.forename: James E
authors.initials: JE
authors.lastname: Allison
authors.forename: Nicole
authors.initials: N
authors.lastname: Flowers
authors.forename: Susan
authors.initials: S
authors.lastname: Hutfless
authors.forename: Fernando S
authors.initials: FS
authors.lastname: Velayos
authors.forename: Geraldine S
authors.initials: GS
authors.lastname: Perry
authors.forename: Robert
authors.initials: R
authors.lastname: Cannon
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: Herrinton
mesh_terms: D000293:Adolescent; D002140:California; D002648:Child; D002675:Child, Preschool; D003093:Colitis, Ulcerative / Q000175:diagnosis* / Q000453:epidemiology*; D003153:Community Health Services / Q000706:statistics & numerical data; D003424:Crohn Disease / Q000175:diagnosis* / Q000453:epidemiology*; D005006:Ethnicity; D005762:Gastroenterology / Q000379:methods; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D015212:Inflammatory Bowel Diseases / Q000175:diagnosis / Q000453:epidemiology; D010372:Pediatrics / Q000379:methods; D015995:Prevalence