title: Status of serum vitamin B12and folate in patients with inflammatory bowel disease in China.
abstract: OBJECTIVE
  Inflammatory bowel disease (IBD) primarily involves the intestinal tract and can affect vitamin absorption. This study was designed to assess the prevalence of vitamin B12and folate deficiencies in patients with IBD, and to identify the risk factors associated with abnormal serum vitamin B12and folate levels.
  
  
  METHODS
  We evaluated the medical records of 195 patients with Crohn's disease (CD) and 62 patients with ulcerative colitis (UC), and selected 118 healthy subjects for the control group.
  
  
  RESULTS
  There were more CD patients with vitamin B12deficiency than UC patients (14.9% vs. 3.2%,P=0.014) and controls (14.9% vs. 4.2%,P=0.003). The prevalence of folate deficiency was higher in CD patients than in controls (13.3% vs. 3.4%,P=0.004). There were no significant differences in the serum vitamin B12and folate statuses of the UC and control groups. Patients with prior ileal or ileocolic resection showed a higher prevalence of abnormal vitamin B12levels than those without prior resection (n=6/16, n=23/179;P=0.018). A disease duration within 5 years was a risk factor of abnormal folate levels in CD patients.
  
  
  CONCLUSIONS
  This study showed that vitamin B12and folate deficiencies were more common in patients with CD than in UC patients and controls. Prior ileal or ileocolonic resection was a risk factor of serum vitamin B12abnormalities, and a disease duration within 5 years was a risk factor of low serum folate levels in CD patients.
authors.affiliation: Division of Gastroenterology and Hepatology, Shanghai Institute of Digestive Disease, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Shaozhong
authors.initials: S
authors.lastname: Huang
authors.affiliation: Division of Gastroenterology and Hepatology, Shanghai Institute of Digestive Disease, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Jiayi
authors.initials: J
authors.lastname: Ma
authors.affiliation: Division of Gastroenterology and Hepatology, Shanghai Institute of Digestive Disease, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Mingming
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Division of Gastroenterology and Hepatology, Shanghai Institute of Digestive Disease, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Ran
keywords: Colitis, ulcerative; Crohn disease; Folate, Inflammatory bowel disease; Vitamin B 12