Long term response to infliximab treatment and its effect on disease course in ulcerative colitis –
A population-based cohort study
S.F.G. Jeuring, P.H.A. Bours, A.W. Ambergen, T.R.A. van den Heuvel, M.J.L. Romberg-Camps, L.E.
Oostenbrug, S.O. Breukink, A.A.M. Masclee, D.M.A.E. Jonkers, M.J. Pierik
Infliximab is an effective treatment for steroid-refractory and steroid-dependent ulcerative colitis (UC).
Information about long term response is scarce and it is still unclear whether the natural disease course of
UC has improved since the introduction of anti-TNF agents. Since anti-TNF treatment is expensive and
has potentially severe side effects, it is important to evaluate its efficacy and to optimise treatment by
identifying markers for response. This study evaluates the effect of anti-TNF availability on the natural
disease course of UC in a population-based cohort and aims to identify clinical predictive markers for
response to infliximab.
Since 1991, all newly diagnosed IBD patients are included in our population-based cohort. Medical
records of all UC patients were reviewed with regard to hospitalisation, colectomy, medication, disease
location at diagnosis, and smoking status and disease location at first infliximab infusion. Two cohorts
were distinguished to analyse the effect of anti-TNF introduction, based on the date of diagnosis and
separated by the year of introduction (i.e. diagnosis in 1991-2004 vs. diagnosis in 2006-2010). Patients
were followed until December 31, 2005 and December 31, 2011, respectively. A Cox proportional hazards
regression model was used to analyse differences in hospitalisation and colectomy between the cohorts
and to assess markers for response to infliximab. Associations were presented as Hazard ratios (HR).
In this study, 1464 UC patients were included. Cohort 1991-2004 comprised 908 patients and cohort
2006-2010 comprised 454 patients. Of the 1464 patients, 109 patients (7.4%) were exposed to infliximab.
Primary response to infliximab was seen in 100 patients (91.7%). Sixty-two patients (56.9%) still used
infliximab 24 months after first infusion. No predictive markers for sustained response to infliximab were
found. The risk of colectomy 12 months after diagnosis, decreased threefold (HR 0.32; 95%CI 0.13-0.79)
since the introduction of anti-TNF treatment. Twenty-four months after diagnosis, the risk of colectomy
decreased 1.5-fold (HR 0.64; 95%CI 0.35-1.18) since anti-TNF introduction. No differences were found in
risk of hospitalisation.
CONCLUSION This study showed that since the introduction of anti-TNF agents, the risk of colectomy is
decreased threefold for at least 12 months after diagnosis, thereby providing new evidence for the efficacy
of anti-TNF in UC. Although costs associated with anti-TNF are high, prevention of colectomies in UC
patients is important since complications after surgery are frequent and patients’ quality of life is often
impaired.