INTESTINAL FAILURE IN CROHN'S DISEASE: A SYSTEMATIC REVIEW AND META-ANALYSIS OF SURGICAL RISK FACTORS

IntroductionIntestinal failure (IF) is a rare but serious complication of Crohn’s disease (CD). However, to date, surgical risk factors remain poorly characterised and data from individual studies can be difficult to interpret or limited. We reviewed the existing literature, to identify surgical factors for IF in CD patients.MethodsAccording to PRISMA guidelines, a systematic review of PubMed for IF and CD was conducted through a series of advanced searches. To identify risk factors, articles related to IF and CD were analyzed according to demographics and CD characteristics, surgical characteristics, and nutritional and medical management. Study quality was assessed using the Item Bank for Assessment of Risk of Bias and Precision for Observational Studies of Interventions or Exposures. Where applicable, a meta-analysis with a random-effects model was performed in R. Results are presented as mean ± standard deviation.Results7 original articles were included with a total of 438 CD patients diagnosed with IF; 6 (85.7%) were retrospective studies and 1 was a prospective study (14.3%). The majority of studies were considered to be of low risk of bias (57.1%), and the remainder had a medium risk of bias (42.9%). From 3 or more studies, the mean age at CD diagnosis from meta-analysis was 28.2 yrs (95% CI: 24.0-32.5, P<0.01, I2=92%), the proportion of males was 42.7%, and the mean proportion of smokers was 35.0%. The mean duration of CD diagnosis before IF and initial surgery were 38.2 yrs ± 10.7 and 6.8 yrs ± 1.1 respectively. From meta-analysis, the mean number of small intestinal resections per patient were 4.7 (95% CI: 3.8-5.6, P<0.01, I2=84%) and the mean estimated length of small bowel remaining was 126.5 cm (95% CI: 102.0-151.0, P<0.01, I2=94%) (Figure 1). The mean estimated original small intestine length was 247.7 cm and the mean proportion of ileocecal valve resections were 87.0% (95% CI: 80.0%-92.0%, P=0.37, I2=0%) (Figure 1). A colon remnant was present in 30.0% (95% CI: 16.0%-45.0%, P<0.01, I2=83%) and the majority of patients had a jejunostomy or ileostomy (70.0%, 95% CI: 48.0%-88.0%, P<0.01, I2=91%). Total length of small bowel resected was 170.0 cm ± 63.8, small bowel resection length per procedure was 77.5 cm ± 52.8, and there was no significant difference in small bowel resection length between elective (79.3 cm ± 65.9) and emergency procedures (118.5 cm ± 81.7).ConclusionsSurgical risk factors in combination with medical and demographic factors can predispose patients to IF. However, certain surgical factors including ileocecal valve resection, presence of an ileostomy or jejunostomy, and small bowel length ≤200 cm could be predictive of the development of IF.