Evolving definitions of remission in Crohn's disease.

BACKGROUND: Using clinical symptoms alone to inform treatment decisions in Crohn's disease (CD) may increase the risk of disease progression and complications. Treatment beyond symptoms may offer improved outcomes.
METHODS: We explore alternative definitions of remission, beyond traditional clinical remission, incorporating more objective parameters of inflammation control, which may support prevention or delay the disease progression. These definitions could serve as a platform for future clinical research, evaluating whether treating beyond symptoms alters the natural history of CD.
RESULTS: Proposed definitions may include endoscopic remission (mucosal healing), normalization of serologic or fecal markers of inflammation, and even radiographic remission, in addition to clinical remission (symptom control). Endoscopic remission is the leading candidate for inclusion because it is the best studied. The definition should include considerations for both early and late disease given that in late disease, which may be associated with operation-related symptoms or irreversible bowel damage, symptomatic remission may not achievable. Desired outcomes in early disease are complete absence of symptoms, no disease progression, no complications or disability, and normal quality of life. In late disease, there are stabilization of noninflammatory symptoms, no progression of damage or disability, and improved quality of life.
CONCLUSIONS: Over time, we anticipate that a working definition of remission that includes both biological remission and clinical remission will evolve and be evaluated in clinical trials. Our proposed definition is a possible starting point for that evolution. Ultimately, the goal in evolving the definition of remission is to improve the outcomes in patients with CD.