Status of serum vitamin B(12) and folate in patients with inflammatory bowel disease in China

BACKGROUND/AIMS: Inflammatory bowel disease (IBD) primarily involves the intestinal tract and can affect vitamin absorption. This study was designed to assess the prevalence of vitamin B(12) and folate deficiencies in patients with IBD, and to identify the risk factors associated with abnormal serum vitamin B(12) and 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 B(12) deficiency 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 B(12) and folate statuses of the UC and control groups. Patients with prior ileal or ileocolic resection showed a higher prevalence of abnormal vitamin B(12) levels 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 B(12) and 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 B(12) abnormalities, and a disease duration within 5 years was a risk factor of low serum folate levels in CD patients.