Quality of life is closely related to anemia in patients with inflammatory bowel disease (IBD). Several studies have reported on anemia in patients with IBD in Western countries. This study investigated the prevalence and clinical characteristics of anemia in Korean patients with IBD.

We reviewed the medical records of 92 patients with ulcerative colitis (UC) and 76 patients with Crohn's disease (CD) who were followed regularly at a single tertiary medical center in Korea between January 2003 and December 2012. Hemoglobin (Hb) thresholds used to define anemia were <13.0 g/dL in men and <12.0 g/dL in women according to the World Health Organization criteria. We chose the lowest Hb level in each year as a representative value because Hb levels changed at each examination and anemia was associated with disease deterioration. The relationship between clinical variables and lowest Hb level was assessed.

The prevalence of anemia was 36.3% in patients with UC and 41.6% in patients with CD. Anemia in patients with CD was associated with hospital admission, 5-aminosalicylate (5-ASA) and infliximab treatment in men. Anemia in patients with UC was associated with hospital admission, oral steroid use, thiopurine and infliximab treatment in men.

The prevalence of anemia in Korean patients with IBD was comparable to that of patients in Western countries. Anemia was associated with male patients with CD who were admitted to the hospital and received medications including 5-ASA and infliximab, and men with UC who were admitted to the hospital and received medications including oral steroids, thiopurine and infliximab.