title: [Relapse rates of ulcerative colitis in remission and factors related to relapse].
abstract: OBJECTIVE
  Ulcerative colitis (UC) is a chronic inflammatory bowel disease with heterogeneous clinical features. Data on the disease course and prognosis of UC patients who have been regularly treated are lacking. We aimed to investigate relapse rates of UC in remission and factors related to relapse.
  
  
  METHODS
  We retrospectively analyzed clinical courses of 84 patients (43 males, median age 43 years, ranged 20-73 years) diagnosed as UC at Ajou University Hospital between January 1997 and December 2005 based on clinical, endoscopic and pathologic findings, and who were regularly followed for at least one year after the remission.
  
  
  RESULTS
  Study subjects consisted of 32 proctitis (38%), 21 left-sided colitis (25%), and 31 subtotal or total colitis (37%). Of 84 patients, relapse was observed in 52 patients (62%) during the follow-up period (ranged 1-9 years). The relapse rate was 24%, 41%, 51%, 65%, 71%, and 79% at 1 year, 2 years, 3 years, 4 years, 5 years and 6 years, respectively. Among sex, age, hemoglobin, ESR, and the extent of disease on admission, decrease of hemoglobin level was the only independent factor related to relapse (odds ratio=2.67, 95% CI (1.32-5.42), p<0.01).
  
  
  CONCLUSIONS
  In Korea, relapse of UC in remission is not rare. Decrease of hemoglobin level is an independent risk factor related to its relapse, while the extent of disease is not.
authors.affiliation: Department of Gastroenterology, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Byoung Joon
authors.initials: BJ
authors.lastname: Park
authors.forename: Kwang Jae
authors.initials: KJ
authors.lastname: Lee
authors.forename: Jae Chul
authors.initials: JC
authors.lastname: Hwang
authors.forename: Sung Jae
authors.initials: SJ
authors.lastname: Sin
authors.forename: Jae Yeon
authors.initials: JY
authors.lastname: Chung
authors.forename: Sung Won
authors.initials: SW
authors.lastname: Cho
mesh_terms: D000328:Adult; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D000963:Antimetabolites / Q000627:therapeutic use; D001379:Azathioprine / Q000627:therapeutic use; D002908:Chronic Disease; D003093:Colitis, Ulcerative / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D003627:Data Interpretation, Statistical; D005260:Female; D005500:Follow-Up Studies; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008297:Male; D019804:Mesalamine / Q000627:therapeutic use; D008875:Middle Aged; D016017:Odds Ratio; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000963:Antimetabolites; D006454:Hemoglobins; D019804:Mesalamine; D001379:Azathioprine