Impact of Obesity on Short- and Intermediate-Term Outcomes in Inflammatory Bowel Diseases: Pooled Analysis of Placebo Arms of Infliximab Clinical Trials.

BACKGROUND AND AIMS: To assess whether obesity may affect natural history of inflammatory bowel diseases (IBD), we conducted an individual participant data (IPD) pooled analysis of placebo arms, using data from clinical trials of infliximab in IBD and using the Yale Open Data Access (YODA) Project.

METHODS

We obtained IPD from 4 placebo-controlled trials of infliximab in adults with IBD (ACCENT-I and ACCENT-II; ACT-1 and ACT-2). Patients were categorized into quartiles based on body mass index (BMI) or weight at time of trial entry. Primary outcome was clinical remission (Crohn's disease activity index [CDAI]<150, Mayo Clinic Score <3); secondary outcomes were clinical response and mucosal healing. Using multivariable logistic regression analysis, we compared association between quartiles of BMI (or weight) and achieving remission, after adjusting for sex, smoking, disease activity, and concomitant prednisone or immunomodulators.

RESULTS

We included 575 placebo-treated patients (mean age 38 years, 51.6% males, 16% obese). Obesity was not associated with odds of achieving clinical remission (Q4 vs Q1: adjusted OR, 1.36; 95% CI, 0.65-2.89; P-value for trend = 0.57), clinical response (Q4 vs Q1: adjusted OR, 1.31; 95% CI, 0.61-2.81; P = 0.45), or mucosal healing remission (Q4 vs Q1: adjusted OR, 0.55; 95% CI, 0.12-2.34; P = 0.31). These results were consistent across strata based on disease type (CD and ulcerative colitis) and trial design (induction and maintenance therapy).

CONCLUSIONS

Based on IPD pooled analysis of placebo arms, obesity does not significantly impact short- and intermediate-term clinical outcomes in patients with IBD. The impact of obesity on long-term patient-important outcomes like surgery and hospitalization merits evaluation.