Appendectomy does not decrease the risk of future colectomy in UC: results from a large cohort and meta-analysis

Abstract

Objectives Early appendectomy is inversely associated with the development of ulcerative colitis (UC). However, the impact of appendectomy on the clinical course of UC is controversial, generally favoring a milder disease course. We aim to describe the effect appendectomy has on the disease course of UC with focus on the timing of appendectomy in relation to UC diagnosis. Design Using the National Institute of Diabetes and Digestive and Kidney Diseases IBD Genetics Consortium database of UC patients, the risk of colectomy was compared between patients who did and did not undergo appendectomy. In addition, we performed a meta-analysis of studies which examined the association between appendectomy and colectomy. Results 2980 UC patients were initially included. 111 (4.4%) UC patients had an appendectomy; of which 63 were performed prior to UC diagnosis, and 48 after diagnosis. In multivariable analysis, appendectomy performed at any time was an independent risk factor for colectomy (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.1 – 3.1), with appendectomy performed after UC diagnosis most strongly associated with colectomy (OR: 2.2; 95% CI 1.1 – 4.5). An updated meta-analysis showed appendectomy performed either prior to or after UC diagnosis had no effect on colectomy rates. Conclusions Appendectomy performed at any time in relation to UC diagnosis was not associated with a decrease in severity of disease. In fact, appendectomy after UC diagnosis may be associated with a higher risk of colectomy. These findings question the proposed use of appendectomy as treatment for UC.

Prospective cohort study of appendicectomy for treatment of therapy-refractory ulcerative colitis

“…It is concerning that some studies have suggested there may be an increased risk of high‐grade dysplasia and colorectal cancer in patients with ulcerative colitis who have undergone appendicectomy. However, a recent systematic review and meta‐analysis suggested that this may be due to colectomy being postponed owing to the positive effect of appendicectomy on disease activity.…”

Clinical Predictors and Natural History of Disease Extension in Patients with Ulcerative Proctitis

“…Third, appendix may serve as a reservoir for commensal bacteria and therefore its removal could lead to more dynamic changes in the colonic microbiota. Despite compelling evidence suggesting protective role of appendectomy on development of UC, it remains largely unclear whether appendectomy plays a role in the clinical course of patients with UC or proctitis 21,22 . In our study, we also demonstrated appendectomy was associated with increased risk of extension in patients with ulcerative proctitis.…”

Fetal and early life antibiotics exposure and very early onset inflammatory bowel disease: a population-based study

“…While genetic factors clearly play an important role in the aetiology of IBD,7–10 they cannot explain the recent rise in disease incidence or the proband concordance rate of 38%–62% in monozygotic twins with CD (even less in UC) 11 12. This has encouraged a search for environmental factors and led to the identification of factors such as smoking, oral contraceptives and appendectomy due to appendicitis (data on appendectomy have however been contradictory)13 as potential risk factors in adulthood IBD while less is known for childhood IBD 14–19…”