title: Association of age at diagnosis and ulcerative colitis phenotype.
abstract: BACKGROUND
  Ulcerative colitis (UC) primarily affects young adults; however, 12% of patients are diagnosed at an advanced age. Previous studies report that older patients are less likely to have pancolitis and more likely to have distal disease location.
  
  
  OBJECTIVE
  Our objective was to compare UC phenotype by age of diagnosis in a tertiary referral cohort.
  
  
  METHODS
  Retrospective database analysis. Demographics, disease extent, and EIM were compared by the following age of diagnosis groups: <17 years, 17-40 years, and >40 years.
  
  
  RESULTS
  A total of 260 patients evaluated between July 1, 2004 and April 19, 2010 were included. Race, smoking history, extraintestinal manifestations of disease, and disease duration were significantly associated with age of diagnosis. As age of diagnosis increased, the proportion of non-white patients increased (p = 0.04), former smoking history increased (p < 0.001), extraintestinal manifestations of disease decreased (p < 0.017), and disease duration decreased (p < 0.0001). As age of diagnosis increased, there was a trend for a higher proportion of patients with proctitis and a decreased proportion of patients with pancolitis. Multivariable analysis adjusting for sex, race, smoking history, family history, and disease duration demonstrated that diagnosis at >40 years was associated with a decreased likelihood for pancolitis compared to younger cohorts (OR 0.43, 95% CI 0.24, 0.76).
  
  
  CONCLUSIONS
  Diagnosis of ulcerative colitis after age 40 years was associated with decreased disease extent compared to younger age groups, even after adjustment for sex, race, smoking history, family history, and disease duration. Our results suggest that older patients have distinct clinical phenotypes.
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Medicine, University of Maryland School of Medicine, 100 North Greene Street, Lower Level, Baltimore, MD 21201, USA.
authors.forename: Sandra M
authors.initials: SM
authors.lastname: Quezada
authors.forename: Raymond K
authors.initials: RK
authors.lastname: Cross
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D003093:Colitis, Ulcerative / Q000175:diagnosis* / Q000473:pathology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D010641:Phenotype; D012307:Risk Factors; D055815:Young Adult