Cost-of-illness of inflammatory bowel disease patients treated with anti-tumour necrosis factor: A French large single-centre experience.

Background: No study has evaluated the direct annual costs of inflammatory bowel disease patients treated with anti-tumour necrosis factor therapy.
Objectives: The purpose of this study was to identify annual direct costs and main cost drivers of anti-tumour necrosis factor-treated inflammatory bowel disease patients.
Methods: All inflammatory bowel disease patients treated with infliximab or adalimumab at Nancy University Hospital were consecutively screened for inclusion from November 2016-February 2017. Data about hospitalisation, surgery, medication, outpatient visits, investigations and transport over the previous 12 months were retrospectively collected.
Results: A total of 108 patients (n = 83 Crohn's disease; n = 25 ulcerative colitis) were included. The mean annual cost per patient was €15,775 (standard deviation €7221), with no difference between Crohn's disease and ulcerative colitis (p = 0.2). The main cost driver was medication, which accounted for 84% of the total direct cost. Hospitalisation and surgery represented 11% and 2% of the direct costs. History of switch to another anti-tumour necrosis factor treatment was identified as the only independent predictor of greater direct costs in the multivariate analysis (p = 0.0018). Conclusions: In a French tertiary referral centre, direct costs of anti-tumour necrosis factor therapy-treated patients were mainly driven by medication, while hospitalisation and surgery represented only a minor part of the costs. There was no difference between Crohn's disease and ulcerative colitis patients.