Idiopathic inflammatory demyelinating disease of the central nervous system in patients with inflammatory bowel disease: Retrospective analysis of 9095 patients

Background: Anti-TNFα biologics induce and maintain remission in inflammatory bowel disease (IBD). Also, they have been reported to induce or unmask idiopathic inflammatory demyelinating disease of the central nervous system (IIDD). Aim: To determine if anti-TNFα biologics increased the risk of IIDD in a large cohort of patients with IBD. Methods: We retrospectively identified adult patients referred to the Mayo Clinic, Rochester, MN for management of IBD from a five state capture area (Minnesota, Wisconsin, North Dakota, South Dakota and Iowa) between 1996 and 2010. IIDDs were identified in both Crohn's disease (CD) and ulcerative colitis (UC) patients with and without anti-TNFα exposure using the 2010 McDonald MRI criteria. The risk of IIDDs in patients with and without anti-TNFα exposure was estimated for IBD; CD and UC groups separately. Results: A total of 9095 patients with IBD were identified (4342 CD and 4753 UC). Four patients with CD with exposure to anti-TNFα agents (4/2054) and five patients with CD without anti-TNFα exposure (5/2288) developed a confirmed IIDD. One patient with UC with exposure to anti-TNFα agents (1/1371) and five patients with UC without anti-TNFα agents developed a confirmed IIDD (5/3382). The per cent of IIDDs in patients with and without anti-TNFα exposure was; IBD: 0.15% and 0.18% (RR = 0.83, 95% CI: 0.28-2.42; P = 0.729); CD: 0.19% and 0.22% (RR = 0.89, 95% CI: 0.24-3.31; P = 0.863); UC: 0.07% and 0.15% (RR = 0.49, 95% CI: 0.06-4.22; P = 0.510). Conclusion: Anti-TNFα biologics do not appear to impact the risk of developing clinical idiopathic inflammatory demyelinating disease in patients with inflammatory bowel disease.