P614 Anti-TNFs more frequently stopped due to loss of response in British Asians with Crohn's disease: a single centre retrospective analysis

Abstract

Background The prevalence of IBD among British Asian populations matches that of British Caucasians within 2 generations of migration. However response to treatment within this population has not been reported. This study investigates whether indications for and response to anti TNF therapy vary with ethnicity. Methods The electronic records for patients under follow up between Sept 2015 and Sept 2016 at a large London IBD centre were studied, and patients ever prescribed anti-TNF were identified. Data collected included: disease onsetphenotype, indication for x to first anti-TNF, and duration indication for withdrawal (sustained remission, primary non response, loss of response>3 months or intolerance). Ethnicity was ascertained as per UK standard coding and categories grouped as Caucasian, Asian or Black. Results 484 patients were identified from electronic records. 131 patients were excluded; 22 with mixed ethnicity, the remainder with incomplete records. Following exclusions, 223 Caucasian, 105 Asian and 25 Black patients remained (Total n= 353). 245 received infliximab, 105 adalimumab,p; 2 unspecified. The mean age was 33.3 years (16-74) with 59.2% (n=209) male and 41.8% (n=144) female. 77.6% (n=274) had CD, 19.2% (n=68) had UC, the remainder had IBD-U. All UC and 63.91% (n=175) CD patients were treated for exclusively luminal disease; the remainder had luminal with either fistula or perianal disease. Indications did not vary with ethnicity (Chi sq. p=0.1697). There was no difference in age at diagnosis with ethnicity for CD or UC. The median (IQR) disease duration to first anti-TNF varied with ethnicity: Caucasians 7.8 (2.3-12.6) yrs; Asians 4.3 (2.0-7.3) yrs; Black 4.9 (2.1-9.7) yrs (Kruskal-Willis, p=0.0014, N=314). Asian patients with CD were prescribed anti-TNF a median 3.8 years earlier in disease course than Caucasians (Mann Whitney p=0.0002 N=229). 190 patients had stopped anti-TNF therapy at the time of review; 165 had a clearly documented stop and start date. Of these, the median (IQR) duration to stopping was 1.2 (0.5-2.3) yrs and did not vary with ethnicity (Kruskal-Wallis p=0.9589). The indication for stopping anti-TNF varied with ethnicity(Chi Sq p= 0.0010) FIGURE 1. Sub analysis of CD only showed that fewer Asians stopped due to sustained remission (Chi Sq with Yates correction p=0.0392). This trend was not seen within UC (p=0.1488) Conclusion(s): Asian patients with IBD receive an anti-TNF sooner, but are more likely to have loss of response and are less likely to experience sustained remission. (Figure Presented).