P002 The use of probiotics in the maintenance of remission in ulcerative colitis: A systematic review
Authors: Zipporah Iheozor-Ejiofor , Lakhbir Kaur , Morris Gordon , Patricia Baines , Anthony Akobeng 
Published: July 2019

BACKGROUND:
Ulcerative colitis (UC) is a chronic relapsing disease characterised by diffuse mucosal inflammation limited to the colon. Current maintenance treatments have multiple adverse events and an effective treatment with minimal adverse events is desired. Several studies have demonstrated the importance of intestinal flora in the pathogenesis of ulcerative colitis. It has been suggested that modifying the bacteria flora with probiotics may attenuate the inflammatory process and prevent relapses in UC.

METHODS:
Data extraction and risk of bias assessment of included studies were independently performed by 2 authors, data was analysed using Review Manager 5.3, dichotomous and continuous outcomes were expressed as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). The certainty of evidence was assessed using GRADE methodology.

RESULTS:
Eleven studies (1,204 randomised participants) met the inclusion criteria. The studies compared probiotics to placebo, probiotics to 5-ASA and a combination of probiotics and 5-ASA to 5-ASA. The risk of bias was high in all except 3 studies due to selective reporting, incomplete outcome data and lack of blinding, this results in low to very low rating of the quality of the evidence. There is no clear difference in relapse when probiotics are compared with placebo (RR, 0.86; 95% CI, 0.71–1.04; 341 participants, 5 studies; low quality of evidence). There is no clear difference in maintenance of remission when probiotics are compared with 5-ASA (RR, 1.05; 95% CI, 0.89–1.24; 122 participants; 2 studies; low quality of evidence). There is no clear difference in maintenance of remission when probiotics coupled with—ASA are compared to 5-ASA alone (RR, 1.49; 95% CI, 0.86–2.57; 92 participants; 2 studies; very low quality evidence).

CONCLUSION(S):
Given the limited data and high risk of bias in the included studies, there is insufficient evidence to make conclusion about the efficacy of probiotics for maintenance of remission in UC. This is based on low to very low quality of evidence. This review highlights the need for further well-designed randomised controlled trials (RCT) to investigate the above objective. Future research should focus on comparing probiotics with 5-ASA as this will reflect clinical practise, patients are unlikely to not be on any treatment to maintain remission. Additionally, length of follow up of most studies in this review is much less than other published reviews, studies looking at 12 months or less are simply too limited in their usefulness to clinical practise. Overall this is the second review for the above objective and it is surprising to see that similar issues exist that did in the first review such as small participants numbers. The issues highlighted in this review should be taken into account for any authors that wish to produce well-designed RTCS looking at the usefulness of probiotics for patients with UC. Some staff received funding from NIHR Cochrane programme.