RESUMO
INTRODUCTION: Obesity is an emerging phenomenon among patients with inflammatory bowel disease (IBD). This study aims to evaluate whether the response to tumour necrosis factor-α (TNF-α) inhibitors (infliximab and adalimumab) could be influenced by BMI in IBD. METHODS: We identified a cohort of 181 IBD patients attending a single-tertiary centre, naive to biologic therapy and stratified them according to their BMI. The primary outcome is the first occurrence of loss of response (LOR). RESULTS: The median BMI was 26 kg/m2 (15-63 kg/m2). Approximately 68% of patients had LOR on both adalimumab (ADA) (n = 52) and infliximab (IFX) (n = 71). However, 83% on ADA with BMI ≥30 kg/m2 had LOR compared to 61% on IFX with BMI ≥30 kg/m2. For patients on ADA, Cox regression analysis revealed that after accounting for age, sex, disease type, duration of disease, fistulising disease, smoking status, haemoglobin, C-reactive protein, albumin and platelet levels, there were statistically significant associations between BMI (≥30 kg/m2 vs. <30 kg/m2) and LOR [P = 0.010; hazard ratio (HR) 3.2; confidence interval (CI), 1.3-7.6]. However, for patients on IFX, after accounting for the same factors, the only significant factor was the association of lower rate of LOR with higher albumin levels (P = 0.024; HR 0.95; CI, 0.91-0.99). There was an increased accelerated time to LOR for patients on ADA with BMI ≥30 kg/m2 compared to BMI <30 kg/m2 (P = 0.026). However, there was no difference in time to LOR for patients on IFX (P = 0.177). CONCLUSION: BMI is important in predicting the LOR among IBD patients on TNF-α inhibitors, especially among patients receiving ADA.
