Increased risk of developing Crohn's disease or ulcerative colitis in 17 018 patients while under treatment with anti-TNFα agents, particularly etanercept, for autoimmune diseases other than inflammatory bowel disease.

Patients treated for autoimmune diseases with anti-TNFα had an increased risk of being diagnosed with CD or UC while under treatment with etanercept. The nature of this association is uncertain. This finding has relevance to clinical care and insights into common mechanisms of the pathophysiology of these diseases.