Song EM, Lee HS, Kim YJ, et al. - The clinical impact of perianal Crohn disease (CD) (pCD), a well-known poor prognostic factor of CD, has not been fully evaluated in Asian patients. The present study was conducted to explore the outcomes of CD in Korean patients according to the presence of pCD at CD diagnosis. Researchers assessed the disease course of CD according to the presence of pCD at CD diagnosis using 2010–2014 data from the national health insurance claims database. The outcomes were confirmed in a hospital-based cohort of 2,923 patients. The data demonstrate that the clinical impact of pCD on the overall outcomes of patients with CD may be less significant in Asian patients compared with Western patients, although the presence of pCD increased the risk of proctectomy and anorectal cancer in Asian patients.