Status of serum vitamin B₁₂ and folate in patients with inflammatory bowel disease in China

ABSTRACT

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 B₁₂ and folate deficiencies in patients with IBD, and to identify the risk factors associated with abnormal serum vitamin B₁₂ 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 B₁₂ 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 B₁₂ and folate statuses of the UC and control groups. Patients with prior ileal or ileocolic resection showed a higher prevalence of abnormal vitamin B₁₂ 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 B₁₂ 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 B₁₂ abnormalities, and a disease duration within 5 years was a risk factor of low serum folate levels in CD patients.