When compared directly with insulin, the use of DPP-4 inhibitors was associated with an over twofold increase in the risk of IBD (HR, 2.28, 95% CI, 1.07-4.85).
The use of DPP-4 inhibitors was also associated with a greater than twofold increase in the risk of ulcerative colitis but no significant effect was seen for Crohn’s disease. However, the authors noted that this result was based on relatively few events and should be interpreted with caution.
The research did not find any difference in risk across different DPP-4 inhibitor drugs.
The DPP-4 enzyme is known to be expressed on the surface of cell types involved in immune response, and patients with IBD have been found to have lower serum DPP-4 enzyme concentrations than healthy controls.