title: Ulcerative colitis: patient characteristics may predict 10-yr disease recurrence in a European-wide population-based cohort.
abstract: OBJECTIVE
  Cumulative 10-yr relapse rates in ulcerative colitis (UC) of 70% to almost 100% have been reported in regional studies. The aim of this study was to determine the relapse rate in UC in a European population-based cohort 10 yr after diagnosis and to identify factors that may influence the risk of relapse.
  
  
  METHODS
  From 1991 to 1993, 771 patients with UC from seven European countries and Israel were prospectively included in a population-based inception cohort and followed for 10 yr. A relapse was defined as an increase in UC-related symptoms leading to changes in medical treatment or surgery. The cumulative relapse rate, time to first relapse, and number of relapses in the follow-up period were recorded and possible causative factors were investigated.
  
  
  RESULTS
  The cumulative relapse rate of patients with at least one relapse was 0.67 (95% CI 0.63-0.71). The time to first relapse showed a greater hazard ratio (HR) (1.2, CI 1.0-1.5) for women and for patients with a high level of education (1.4, CI 1.1-1.8). The number of relapses decreased with age, and current smokers had a lower relapse rate (0.8, CI 0.6-0.9) than nonsmokers. The relapse rate in women was 1.2 (CI 1.1-1.3) times higher than in men. An inverse relation was found between the time to the first relapse and the total number of relapses.
  
  
  CONCLUSIONS
  In 67% of patients, there was at least one relapse. Smoking status, level of education, and possibly female gender were found to influence the risk of relapse.
authors.affiliation: Sörlandet Hospital Arendal, Department of Medicine, Section for Gastroenterology, Arendal, Norway.
authors.forename: Ole
authors.initials: O
authors.lastname: Höie
authors.forename: Frank
authors.initials: F
authors.lastname: Wolters
authors.forename: Lene
authors.initials: L
authors.lastname: Riis
authors.forename: Geir
authors.initials: G
authors.lastname: Aamodt
authors.forename: Camilla
authors.initials: C
authors.lastname: Solberg
authors.forename: Tomm
authors.initials: T
authors.lastname: Bernklev
authors.forename: Selwyn
authors.initials: S
authors.lastname: Odes
authors.forename: Iannis A
authors.initials: IA
authors.lastname: Mouzas
authors.forename: Marina
authors.initials: M
authors.lastname: Beltrami
authors.forename: Ebbe
authors.initials: E
authors.lastname: Langholz
authors.forename: Reinhold
authors.initials: R
authors.lastname: Stockbrügger
authors.forename: Morten
authors.initials: M
authors.lastname: Vatn
authors.forename: Bjorn
authors.initials: B
authors.lastname: Moum
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003093:Colitis, Ulcerative / Q000453:epidemiology / Q000503:physiopathology*; D004522:Educational Status; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D012737:Sex Factors; D012907:Smoking