Patterns of anti-TNF use and associated treatment outcomes in inflammatory bowel disease patients: results from an analysis of Dutch health insurance claims data

Introduction: Real-life patterns of anti-tumour necrosis factor (anti-TNF) use remain largely unknown. We aimed to investigate survival rates, clinical outcomes and costs of anti-TNF agents in a large population of patients with inflammatory bowel disease (IBD). Methods: Health insurance data from 22,082 IBD patients were provided by Achmea Healthcare. Time to anti-TNF discontinuation, treatment intensification, corticosteroid initiation and hospitalisation were analysed in patients starting on anti-TNF treatment from January 2008 until December 2014. Treatment regimens were analysed at different time points. Results: In this cohort, 855 and 1199 subjects started infliximab and adalimumab treatment, respectively. The median time to anti-TNF discontinuation was 600 days (IQR 156-1693). The proportion of subjects receiving intensified treatment increased over time (infliximab at 3 vs. 24 months: 22.2% vs. 33.6%, p = 0.01; adalimumab at 3 vs. 24 months: 10.5% vs. 19.3%, p <0.001). Cessation of anti-TNF treatment was less common in Crohn's disease patients (HR 0.79, p = 0.001) and in patients receiving intensified treatment (HR 0.62, p = 0.001). Immunomodulator use was associated with a longer time to corticosteroid initiation (HR 0.80, p = 0.048), but not with longer drug survival (HR 0.99, p = 0.617). Hospitalisation was more common in Crohn's patients (HR 1.49, p = 0.011). Corticosteroid initiation was lower in Crohn's patients (HR 0.57, p <0.001) and in patients using infliximab (HR 0.55, p <0.001). Conclusions: Discontinuation of anti-TNF therapy occurred earlier than previously reported and was associated with a diagnosis of ulcerative colitis and non-intensified anti-TNF treatment. Immunomodulator use at the start of anti-TNF treatment was associated with a longer time to corticosteroid initiation, but not with longer drug survival