Prevalence and Risk Factors for Functional Vitamin B12 Deficiency in Patients with Crohn's Disease

Ward MG1, Kariyawasam VC, Mogan SB, Patel KV, Pantelidou M, Sobczyńska-Malefora A, Porté F, Griffin N, Anderson SH, Sanderson JD, Harrington DJ, Irving PM. Inflamm Bowel Dis. 2015 Aug 19. [Epub ahead of print]
Author information

1*Department of Gastroenterology, Guy's and St Thomas' Hospital NHS Foundation Trust, London, United Kingdom; †The Nutristasis Unit, Viapath, St Thomas' Hospital, London, United Kingdom; ‡Department of Radiology, Guy's and St Thomas' Hospital NHS Foundation Trust, London, United Kingdom; and §Diabetes and Nutritional Sciences Division, School of Medicine, King's College London, London, United Kingdom.


BACKGROUND: Crohn's disease (CD) is a risk factor for vitamin B12 deficiency due to frequent involvement of the terminal ileum. Conventional screening for B12 deficiency with serum B12 is relatively insensitive and measures total B12 concentration, of which a minority is present in a biologically active form. Holotranscobalamin (holoTC) combined with methylmalonic acid (MMA) is believed to be more accurate in identifying impaired B12 status. We evaluated the prevalence and risk factors for B12 deficiency using holoTC supported by MMA among patients with CD.

METHODS: We performed a single-center service evaluation of 381 patients with CD who underwent B12 assessment (holoTC/MMA) and compared them with 141 patients with ulcerative colitis. Eighty-nine patients with CD underwent paired serum B12 and holoTC. Among patients with CD, risk factors including terminal ileal resection length, ileal inflammation on endoscopy, and disease characteristics on magnetic resonance imaging were recorded.

RESULTS: Prevalence of B12 deficiency among patients with CD was 33% compared with 16% in ulcerative colitis (P < 0.0001). In 89 patients who underwent paired tests, conventional testing identified B12 deficiency in 5% of patients with CD, which increased to 32% using holoTC/MMA. Independent risk factors for B12 deficiency were ileal resection length ≤20 cm (odds ratio: 3.0, 95% confidence interval, 1.5-6.0, P = 0.002) and >20 cm (odds ratio: 6.7, 95% confidence interval, 3.0-14.7, P < 0.0001) and ileal inflammation (odds ratio: 3.9, 95% confidence interval, 2.2-6.9, P < 0.0001). On magnetic resonance imaging, active terminal ileal inflammation (P = 0.02) and an increased disease burden (≥1 skip lesion, P = 0.01 and prestenotic dilatation >3 cm, P = 0.01) were associated with B12 deficiency.

CONCLUSIONS: Vitamin B12 deficiency is common in patients with CD. The holoTC supported by MMA identifies patients with B12 deficiency considered replete on conventional testing.

© Copyright 2013-2024 GI Health Foundation. All rights reserved.
This site is maintained as an educational resource for US healthcare providers only. Use of this website is governed by the GIHF terms of use and privacy statement.