title: Crohn's disease in Stockholm County during 1990-2001: an epidemiological update.
abstract: OBJECTIVE
  To further assess of the incidence and localization of Crohn's disease (CD) in a well-defined population during the 1990s and to evaluate the prevalence of CD on the 1st of January 2002.
  
  
  METHODS
  In a retrospective population based study, all 16-90 years old citizens of Stockholm County diagnosed as having CD according to Lennard Jones' criteria between 1990 and 2001 were included. Case identification was made by using computerized inpatient and outpatient registers. Moreover private gastroenterologists were asked for possible cases. The extent of the disease and the frequency of anorectal fistulae were determined as were the ages at diagnosis. Further, the prevalence of CD on the 1(st) of January 2002 was assessed.
  
  
  RESULTS
  All the 1 389 patients, 689 men and 700 women, fulfilled the criteria for CD. The mean incidence rate for the whole period was 8.3 per 10(5) (95%CI 7.9 -8.8). There was no difference between the genders. The mean annual incidence of the whole study period for colorectal disease and ileocecal disease, was 4.4 (95%CI 4.0-4.7) and 2.4 (95%CI 2.1-2.6) per 10(5), respectively. Perianal disease occurred in 13.7% (95%CI 11.9-15.7 %) of the patients. The prevalence of CD was 213 per 100,000 inhabitants.
  
  
  CONCLUSIONS
  The incidence of CD has markedly increased during the last decade in Stockholm County and 0.2% of the population suffers from CD. The increase is attributed to a further increase of colorectal disease, while the incidence of ileocecal disease has remained stable.
authors.affiliation: Centre of Gastroenterology, Ersta Hospital, Box 4622, S-11691 Stockholm, Sweden. annika.lapidus@ersta.se
authors.forename: Annika
authors.initials: A
authors.lastname: Lapidus
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003424:Crohn Disease / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors