AIBD 2010: Studies Identify Predictors of IBD Severity, Complications

Several predictors may help clinicians determine which patients with inflammatory bowel disease (IBD) are at risk for more severe disease and potential complications. Diagnosis and treatment of IBD earlier in the course of disease leads to improved outcomes, and potentially reduces the risk of more severe IBD by changing the natural course of the disease, according to research presented at the 2010 Advances in Inflammatory Bowel Diseases, the Crohn's & Colitis Foundation's Clinical & Research Conference, being held December 9-12 in Hollywood, FL.

During a session focusing on topics in IBD, Edward V. Loftus, MD, of the Mayo Clinic, Rochester, MN, outlined the natural history of ulcerative colitis (UC) and Crohn’s disease (CD) and implications for choice of treatment. He focused on predicators of disease behavior in CD and UC; circumstances surrounding the course of disease, including changes in the natural history of disease due to treatment; and the use of diagnostic testing to optimize treatment.

In looking at the natural history of UC, recent studies have shown that the cumulative risk of hospitalization and colectomy increased with more recent diagnosis, more extensive disease, initial need for corticosteroids, and initial need for hospitalization. Similar trends have been found when looking at the natural history of CD. In one study completed in France, investigators defined a composite endpoint to evaluate predictors of disabling CD. The investigators evaluated a cohort of 1,128 CD patients and found that disabling CD course within five years was associated with initial requirement for steroids, age at diagnosis below 40 years, and perianal disease at diagnosis. Another study that looked at patients diagnosed with CD between 1983 and 1996 in Olmsted County, MN, resulted in similar findings, with disease location the key risk factor associated with complications and perianal disease somewhat tied to complication. Age, gender, family history, extra gastrointestinal manifestation, smoking status, and medication use were not significantly associated with complication.

Predictors of more severe IBD disease in patients with CD include young age of onset, ileal or ileocolonic extent, fistulizing disease at diagnosis, and early need for steroids. For those with UC, predictors of more severe disease include extensive colitis, male gender, early need for steroids, and early hospitalization.

Recent studies have demonstrated that drug treatment may alter the natural course of CD and UC, with earlier treatment more likely to change the natural course of disease. Studies have demonstrated that mucosal healing with drug treatment was associated with less inflammation and decreased future steroid treatment in patients with CD. In the ACCENT I trial, mucosal healing was associated with decreased hospitalizations and surgeries. In addition, mucosal healing with conventional therapy reduced the rate of colectomy in patients with UC.

In the CHARM study, the risk of CD-related hospitalizations was lower among those receiving adalimumab, with shorter duration of CD associated with improved response rates and higher levels of remission to therapy with adalimumab. In the Top Down Versus Step Up study, investigators found that early introduction of treatment was associated with higher rates of steroid-free remission. Intervention with treatment early in the disease course appeared to help to change the natural course of CD or UC and may help to prevent the onset of more severe disease.

According to Loftus, being aware of the clinical predictors of more severe IBD may help physicians determine which patients with CD and UC are at risk for more severe disease and potential complications. Therefore, diagnosis and treatment of IBD earlier in the course of disease may help improve outcomes, change the natural course of disease, and prevent the onset of more severe disease.