Is it possible to change phenotype progression in Crohn's disease in the era of immunomodulators? Predictive factors...

Crohn's disease (CD) induces cumulative structural damage, initially characterized by a non-stenosing non-penetrating behavior (B1) with progression over time to a fibro-stenosing (B2) and/or penetrating phenotype (B3). Our aim was to assess the long-term evolution of disease behavior of CD and determine what factors predict phenotype progression.

This was a study based on prospectively collected data from a CD database in an inflammatory bowel disease outpatient clinic. B1 corresponds to a non-stenosing non-penetrating disease, B2 to a stenosing behavior, and B3 to a penetrating one.

Seven hundred and thirty-six patients with CD (368 female) were followed up for 12.3 years (± 8.4), with 87.0% of them exhibiting B1 phenotype at diagnosis. Of these patients, 28.5% progressed to B2 phenotype and 23.5% to B3. Fifty percent of the patients started azathioprine treatment before phenotype change and 13.9% started anti-tumor necrosis factor-α (anti-TNFα) treatment before phenotype change. Monotherapy with azathioprine before phenotype change as well as combination therapy with azathioprine/anti-TNFα before phenotype change delayed disease progression (B1-B2 or B3) in comparison with patients who did not receive treatment (P<0.001). The hazard ratio (HR) for disease progression was lower for both monotherapy with azathioprine (HR: 0.15, P<0.001) or combination therapy with anti-TNFα (HR: 0.33, P<0.001). Upper gastrointestinal tract involvement, male gender, and steroid use were associated with an early progression of phenotype from B1 to B2 or B3 (P<0.001). The HR for disease progression was higher in patients who used steroids without criteria of dependence or resistance (HR: 2.67, P<0.001) and was even higher in patients with criteria of dependence or resistance (HR: 6.44, P<0.001). Longer delays between CD diagnosis and beginning of therapy with azathioprine and/or anti-TNFα were associated with disease progression. The longer the duration of treatment, the less likely the disease progression.

Monotherapy with azathioprine before behavior change as well as combination therapy with azathioprine and anti-TNFα before behavior change delays phenotype progression of CD, whereas upper gastrointestinal tract involvement, male gender, and steroid use with or without criteria of steroid dependence are associated with a higher risk for disease progression.