A165 DOES APPENDECTOMY PREVENT THE SUBSEQUENT DEVELOPMENT OF ULCERATIVE COLITIS?: A SYSTEMATIC REVIEW AND META-ANALYSIS

Abstract

Abstract Background Ulcerative colitis (UC) is a disease with a heavy burden of morbidity, for which we do not fully understand its etiology. Researchers have anecdotally observed a preventative effect of appendectomy on the risk of developing UC, with multiple studies exploring this relationship. Aims We aimed to complete a systematic review and meta-analysis, the largest of its kind, to determine with more certainty the effect of appendectomy on the subsequent development of UC. Methods A literature search and a review of reference lists of previously published articles was done to identify studies exploring the association between appendectomy and the subsequent development of UC. Our primary endpoint was the diagnosis of UC. Other variables of interest were geographical region, publication date, and age at time of appendectomy. Odds ratios with 95% confidence intervals (CI) are reported. Results Fifty-one studies (49 case-controls studies and 2 cohort studies) were included with a total of 1,270,332 participants. The pooled OR showed that appendectomy decreases the odds of developing UC (Figure 1; OR 0.37, 95% CI, 0.29–0.46, I2 = 89%). A similar pattern was seen for individuals who received an appendectomy before the age of 20 (Figure 2; OR 0.35, 95% CI, 0.21–0.61, I2 0%). The protective effect was seen again when including only high quality methodological studies with Newcastle-Ottawa scale ≥ 7 (Figure 3; OR 0.47, 95% CI, 0.34–0.65, I2 56%). Conclusions Appendectomy may be protective against subsequent development of UC. Future research should focus on the physiological explanation behind this association, and the practicality of using appendectomy as a primary prevention measure in patients at high-risk of developing ulcerative colitis. Funding Agencies None