BACKGROUND/AIMSWhether older patients with ulcerative colitis (UC) have a better clinical course than younger patients is unclear. We compared the clinical characteristics between older and younger age groups in South Korea to elucidate the impact of age on relapse in UC.METHODOLOGYPatients between 18 and 85 years old who were diagnosed with UC at Seoul National University Bundang Hospital between 1 May 2003 and 31 Oct 2007 were enrolled. It was reviewed their symptoms, endoscopic and pathologic findings, and drugs used in induction treatment.RESULTSOf the 73 patients with UC who achieved remission after induction treatment, 38 relapsed. The patients aged 18-44 and 45-85 years had similar clinical features, but the relapse rate was significantly higher in the younger group (69.2 vs. 32.4%; p = 0.002). In a multivariable analysis, age 45-85 years old was an independent protective factor against relapse (OR, 0.146; 95% CI, 0.035-0.508; p = 0.003) after adjusting for sex, frequency of diarrhea, hematochezia grade, disease extent, and systemic steroid used in induction treatment.CONCLUSIONAn age of 45 years or older is an independent predictor of less relapse in UC.