|Probiotics in patients with severe acute pancreatitis: a meta-analysis
|Sun S,Yang K, He X, Tian J, Ma B, Jiang L
The review concluded that enteral feeding with probiotics could not reduce rates of infected necrosis and mortality in patients with severe acute pancreatitis and that further research was needed. The authors' conclusions appear reliable, although they did not highlight the possibility that probiotics may be harmful (as indicated by the largest, best-quality trial).
To investigate whether enteral feeding with probiotics reduced infected necrosis and death in severe acute pancreatitis.
MEDLINE, EMBASE, The Cochrane Library, China Biomedical Literature Database, China Journal Full Text Database and Chinese Scientific Journals Full Text Database were searched without language restrictions; search terms were reported. Reference lists of primary studies and review articles, and abstract booklets were searched. Eligible studies had to be published as full-length articles (or letters) in peer-reviewed journals.
Randomised controlled trials (RCTs) of prophylactic probiotic enteral feeding in patients with severe acute pancreatitis were eligible for inclusion. Studies had to report one of the following outcomes: infected pancreatic necrosis; other infectious complications (chest infection, urinary tract infection, systemic inflammatory response syndrome); mortality; mean duration of hospitalisation; and need of surgery.
All included studies compared enteral probiotic feeding with no probiotic feeding in patients with either alcoholic or biliary aetiologies. Two reviewers independently assessed studies for inclusion.
Assessment of study quality
Two reviewers independently evaluated study quality by assessment of reporting of randomisation method, allocation concealment, outcome assessor blinding and completeness of follow-up.
Data were extracted and odds ratios (OR) and mean differences, with 95% confidence intervals (CI), were calculated.
Two reviewers independently extracted data. Disagreements were resolved by consensus.
Methods of synthesis
Data were pooled using a fixed-effect model meta-analysis or a random-effects model if heterogeneity was found. Sensitivity analyses were planned to examine any influence of study quality criteria. The X2 and I2 tests were used to assess heterogeneity.
Results of the review
Four RCTs (n=428) were included in the review. Sample size ranged from 25 to 296 participants. Two studies were doubled-blinded and in two; in the other two this was unclear. One study used computer-generated randomisation; in the other three this was unclear.
There were no significant differences between groups in incidence of infected pancreatic necrosis (OR 0.56, 95% CI 0.13 to 2.35, I2=64%; three studies), mortality (OR 0.83, 95% CI 0.14 to 4.83, I2=73%; three studies), chest infection (three studies), urinary tract infection (two studies), systemic inflammatory response syndrome (two studies), mean duration of hospital stay (two studies) or the need for surgery (three studies).
The present study showed that enteral feeding with probiotics could not reduce rates of infected necrosis and mortality. Future studies were required to clarify the issues of the effect of probiotics in severe acute pancreatitis.
The review addressed a clear question supported by appropriate inclusion criteria. Several databases were searched without language restrictions The authors searched for unpublished studies, but the restriction to published studies only meant that some relevant trials may have been missed and the review may have been subject to publication bias. Suitable methods were employed to reduce risks of reviewer error and bias throughout the review processes. Study quality was assessed and used in interpreting the results of the review. But, no results were provided on allocation concealment and the follow up criterion was vaguely described and reported, which made it very difficult to interpret. Appropriate methods were used to pool data and assess heterogeneity; possible sources of heterogeneity were discussed. However, little information on probiotics used and patient populations was provided, which made interpretation of results more difficult; the authors stated that trials had different eligibility criteria, but no further details were provided. Only one of the four trials appeared to be appropriately powered, as the number of events in the other trial groups was very low. The authors' conclusions were suitably cautious in recommending further trials and appear likely to be reliable. However, it should be noted that the largest trial, which appeared to be of high quality, suggested that probiotic treatment may possibly have harmful effects.
Implications of the review for practice and research
The authors did not state any implications for practice.
Research: The authors highlighted the importance of using (and reporting) appropriate randomisation, blinding and sample sizes in future placebo-controlled studies, and that such studies should have common eligibility criteria (with severe pancreatic necrosis).
Sun S,Yang K, He X, Tian J, Ma B, Jiang L. Probiotics in patients with severe acute pancreatitis: a meta-analysis. Langenbeck's Archives of Surgery 2009; 394(1): 171-177
Subject indexing assigned by NLM
Comorbidity; Enteral Nutrition; Humans; Mathematical Computing; Odds Ratio; Pancreatitis, Acute Necrotizing /drug therapy /mortality; Probiotics /administration & Survival Rate; Treatment Outcome; dosage
Date bibliographic record published
Date abstract record published
This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.