P546 Endoscopic findings related to the long-term response to anti-TNF-α antibody treatment in patients with Crohn's disease

Abstract

Abstract Background Anti-TNF-α antibody treatment in Crohn's disease patients has been established, but loss of treatment response has become a problem in recent years. No studies have investigated the endoscopic findings related to loss of response particularly in the long-term treatment. In this study, we investigated the endoscopic findings associated with diminished efficacy of anti-TNF-α antibodies in Crohn's disease patients treated over a long period of time. Methods A total of 79 patients with Crohn's disease who were observed for at least 1 year after the anti-TNF-α antibody treatment was initiated at our hospital were included in this study. These patients were stratified into cases with and without loss of response to the anti-TNF-α antibody treatment, and the endoscopic findings were compared between the two groups. A case with loss of response was defined as one in which the dose was increased or the duration of treatment was shortened during the anti-TNF-α antibody treatment or the anti-TNF-α antibody preparation was changed to another due to lack of response to the initial preparation. The findings examined were aphtha, erosion, cobblestone-like mucosa, fistula, multiple ulcer, longitudinal ulcer, and anal lesion. Mann-Whitney's U test, χ2 test, and logistic regression analysis were used for statistical analysis, and differences with p < 0.05 were considered significant. Results The mean observation period for all patients was 85.5 months, and the longest period was 188 months. Of the 79 patients included, 29 met the criteria with loss of response, and 50 did not (loss of response rate 37%). Comparisons between the loss of response group and the no loss of response group by univariate analysis showed that anal lesions (66% vs 42%, p = 0.028), stenosis (75% vs 48%, p = 0.021), and multiple ulcers (82% vs 53%, p = 0.011) were significantly more frequent in the loss of response group. The multivariate analysis on these items identified anal lesions (OR: 3.06, 95% CI 1.04-9.04, p = 0.042) and multiple ulcers (OR: 5.33, 95% CI 1.59-17.9, p = 0.0068) as independent risk factors for loss of response. Conclusion In this study, Crohn's disease patients with endoscopic findings of anal lesions and multiple ulcers were prone to loss of response to the anti-TNF-alpha antibody treatment after long-term administration. This result is considered to be very useful for developing a treatment strategy for patients requiring long-term anti-TNF-α antibody treatment.