P381. Predictors and frequency of anti-TNF dose escalation in patients with inflammatory bowel disease
N. Viazis, T. Koukouratos, J. Anastasiou, E. Saprikis, G. Kechagias, K. Katopodi, M. Mela, D. Karamanolis, Evangelismos Hospital, Gastroenterology Department, Athens, Greece
The efficacy of anti tumor necrosis factor therapy (anti-TNF) in patients with inflammatory bowel disease (IBD) has been demonstrated in several randomized clinical trials. However, some patients do not respond to standard dose and therapy needs to be intensified. We aimed to determine predictors and frequency of anti-TNF dose escalation in patients treated with infliximab or adalimumab for ulcerative colitis (UC) or Crohn's disease (CD), in a tertiary hospital setting.
Prospective analysis of our IBD patients started on anti-TNF therapy for maintenance of remission. All patients were naïve to anti-TNF and received concomitant azathioprine therapy for a period of 6 months, unless they developed adverse events, in which case azathioprine was discontinued earlier. Outcome of anti-TNF therapy was evaluated every 2 months throughout the follow up period. Standard dose of maintenance infliximab therapy was considered that of 5 mg/kg of body weight administered every 2 months and standard dose of adalimumab therapy was considered that of 40 mg administered every 2 weeks. In patients initially responding to anti-TNF and subsequently losing clinical response (symptoms reappearance, CRP re-elevation) at any time period after the first 14 weeks of therapy, dose escalation was scheduled. Chi square test was performed. Statistical significance was inferred at the 0.05 level.
As of September 2010, a total of 161 IBD patients were started on infliximab (n = 96) or adalimumab (n = 65) therapy in our Department (CD = 133, UC = 28). Among them, 29 (18.0%) patients did not respond to anti-TNF therapy and were excluded from further analysis; therefore, the study population consisted of 132 patients (CD = 113, UC = 19; infliximab = 77, adalimumab = 55). The median time of follow up was 26 months (range 2–36 months). During this follow up period 31 patients (23.5%) needed a dose escalation for maintenance of remission (CD = 30, UC = 1). Precisely, 13 (9.8%) received double infliximab dose (10 mg/kg of body weight) every two months, 5 (3.8%) received double the dose every one and a half or one month and 13 (9.8%) received the standard adalimumab dose every week. According to the statistical analysis, predictors for anti-TNF dose escalation were tobacco use in patients with CD, extra-intestinal manifestations of disease in patients with UC and azathioprine discontinuation earlier than 6 months in all patients.
A substantial number of IBD patients (23.5%) will need dose-escalation for maintenance of disease remission. Tobacco use in CD, presence of extra-intestinal manifestations in UC and azathioprine discontinuation earlier than 6 months in all patients can predict the need for anti-TNF dose escalation.