P001 The use of probiotics in the induction of remission in ulcerative colitis: A systematic review
Authors: Lakhbir Kaur , Zipporah Iheozor-Ejiofor , Morris Gordon , Patricia Baines , Anthony Akobeng 
Published: July 2019

BACKGROUND:
Ulcerative colitis (UC) is a disease that causes inflammation of the colon and has an incidence of approximately 10–20 per 100,000 per year. At present, the therapies that exist to treat UC are unfortunately coupled with unfavourable side effects which has resulted in a demand for new alternatives. Probiotics are live microbial feed supplements that may benefit the host by improving intestinal microbial balance, enhancing the gut barrier function and improving local immune response.

METHODS:
Data extraction and risk of bias assessments of included studies were conducted independently by 2 authors. Data was analysed using review manger 5.3. Dichotomous and continuous outcomes were expressed at risk ratio (RR) and mean differences (MDs) with 95% confidence intervals (CIs). The certainty of the evidence was assessed using GRADE methodology.

RESULTS:
Twelve studies (755 randomised participants) met the inclusion criteria, 10 studies looked adults while the remaining 2 looked at paediatric patients. The studies compared probiotics vs placebo, probiotics vs 5-ASA and combination of probiotics plus 5-ASA vs 5-ASA alone. The studies ranged from 2 weeks to 52 weeks. The main results included that probiotics may improve the induction of remission when compared with placebo (RR, 1.73; 95% CI, 1.17–2.56; 560 participants; 8 studies; low quality of evidence) and they probably also improve disease severity when compared with placebo (RR, 1.54; CI, 1.11–2.13; 164 participants; 2 studies; moderate quality evidence). When probiotics are compared to 5-ASA it is uncertain whether they offer better chances of remission (RR, 0.92; 95% CI, 0.73–1.16; 116 participants; 1 study; very low-quality evidence). However, when probiotics are coupled with 5-ASA they may slightly improve the induction of remission compared to 5-ASA alone (RR, 1.22; CI, 1.01–1.47; 84 participants; 1 study; low quality evidence). For adverse events, probiotics did not lead to any serious adverse events in any of the 7 studies which reported on it, however the quality of the evidence was very low (RR, 0.09; CI, 0.01–1.66; 526 participants; 7 studies).

CONCLUSION(S):
There is low quality evidence which suggests that probiotics may be efficacious in inducing remission when compared with placebo. Whilst it is uncertain whether probiotics are more effective than 5-ASA, there is limited evidence that they may slightly improve the induction of remission when used in combination with 5-ASA. There is insufficient evidence to assess whether probiotics are effective in patients with severe and more extensive disease, or if specific preparations are superior to others. Further, targeted and appropriate powering of studies and the use of standardised patients' groups and outcome measures in line with the wider field are needed. In addition, the conception of trials must be considered, for example comparing probiotic to placebo is not representative of current clinical practise where patients who have active disease will be treated with some sort of therapy to aid remission.

Grants/Declarations: Some staff were funded by the NIHR Cochrane Programme.