REPORTING FROM THE CROHN’S & COLITIS CONGRESS
Las Vegas (FRONTLINE MEDICAL NEWS) – Higher body mass index among inflammatory bowel disease patients is independently associated with an increased risk of treatment failure and IBD-related surgery or hospitalization, a single-center, retrospective cohort study demonstrated.
“The problem of IBD and obesity is on the rise,” Soumya Kurnool said at the annual congress of the Crohn’s & Colitis Foundation, a partnership of the Crohn’s & Colitis Foundation and the American Gastroenterological Association. “Today, 15%-40% of IBD patients are obese. This is significant because there is a decreased prevalence of remission and an increased risk of relapse in obese IBD patients. These patients also have a higher annual burden of hospitalization.”
Obesity also is associated with increased drug clearance for all biologic agents and higher odds of failing anti-TNF therapy in other immune-mediated inflammatory diseases, said Ms. Kurnool, a second-year student at the University of California, San Diego. “However, the research on the impact of obesity on treatment response to biologic agents in IBD is sparse and conflicting.”
She and her associates set out to evaluate the effect of obesity on response to biologic therapy in patients with ulcerative colitis (UC). They conducted a single-center, retrospective cohort study of biologic-treated adults with UC who started therapy during 2011-2016. The researchers excluded patients who had undergone a prior colectomy, as well as those who were underweight at the time of starting a biologic agent and those who had fewer than 6 months of follow-up data.
The primary outcome was time to treatment failure, defined as a composite of IBD-related surgery, hospitalization, and/or treatment modification. Secondary outcomes were time to IBD-related surgery and/or hospitalization and whether the patient achieved endoscopic remission within 1 year of starting biologic therapy. They conducted multivariate Cox proportional hazard analyses after adjusting for key confounders.
Ms. Kurnool reported results from 160 patients with a median age of 36 years. Half were male, and the mean follow-up was 24 months. The median BMI of the cohort was 24.3 kg/m2; 26% were overweight and 18% were obese. More than half of patients (55%) were on infliximab with weight-based dosing and 45% were on other fixed-dosing regimens, including 19% on vedolizumab. In terms of outcomes, 68% of patients experienced treatment failure. All who failed treatment underwent treatment modifications; 15% had IBD-related surgery, and 19% had IBD-related hospitalization.
After adjusting for age, sex, disease duration, prior hospitalization, prior anti-TNF therapy, steroid use, and albumin level, Ms. Kurnool and her associates found that every 1-kg/m2 increase in BMI was associated with a 4% higher risk of treatment failure (adjusted hazard ratio, 1.04), an 8% higher risk of surgery or hospitalization (adjusted HR, 1.08), and a 6% lower risk of achieving endoscopic remission (adjusted HR, 0.94).
“This increase in the risk of treatment failure and IBD-related surgery or hospitalization was consistent across strata of patients treated with infliximab and fixed-dosing regimens,” she said. “Based on these findings, physicians should consider proactive monitoring in obese patients treated with biologic agents.”
Ms. Kurnool reported having received a National Institutes of Health Short Term Training Grant from the University of California, San Diego.
SOURCE: Kurnool S et al. Crohn’s & Colitis Congress, Clinical Abstract 24.