Divya Aggarwal and Jimmy K Limdi
Background: Patients with ulcerative colitis (UC) may be exposed to ionizing radiation for evaluation of disease with inherent risks from protracted exposure. Meanwhile, evolving definitions of disease control with evolving treatment paradigms have led to earlier introduction of biological therapy. Our aim was to compare the effective radiation dose prior to and 1 and 3 years after initiating anti- TNF therapy or corticosteroid in patients with UC.
Methods: We performed a retrospective review of UC patients treated with Infliximab or corticosteroids at our institution from 2005-2012.
Results: We analysed 102 patients with ulcerative colitis (66 anti-TNF and 36 corticosteroid treated). Demographics and disease characteristics between the two groups were similar. The decrease in mean number of radiology studies between the year preceding and the year following initiation of therapy was significantly larger in the Infliximab group compared to the corticosteroid group (-2.5 vs. -0.6, CI=-3.3 to -0.4, p=0.009). Linear regression analysis suggested a statistically significant decrease in the number of imaging studies by 2 with the use of Infliximab compared to the corticosteroid group within a year of therapy. Differences between the two groups in the number imaging studies 3 years after therapy and in the cumulative effective radiation dose exposure 1 and 3 years after therapy did not reach statistical significance.
Conclusion: Anti-TNF therapy is associated with a significant reduction in diagnostic imaging exposure at 1 year after therapy.