Efficacy of probiotics in the treatment of minimal hepatic encephalopathy: a systematic review and meta-analysis

Aim of the study:
Patients with minimal hepatic encephalopathy (MHE) have no recognizable clinical symptoms of hepatic encephalopathy (HE), but the mild cognitive and psychomotor deficits have been shown to negatively affect their daily functioning and quality of life. Treatment with probiotics has shown benefit in some clinical trials. This review aimed to systematically analyze the efficacy of probiotics in the treatment of MHE.

Material and methods:
A systematic search of the electronic databases PubMed, Science Direct, and Cochrane Library was conducted for randomized controlled trials (RCTs) in adult patients with MHE who had been given probiotics intervention. The primary outcomes were reversal of MHE and improvement of neuropsychometric tests, while the secondary outcome was the reduction of serum ammonia.

Results:
Nine RCTs involving 776 MHE patients were included, consisting of 311 patients receiving probiotics and 465 patients receiving comparator (placebo or no treatment, lactulose, L-ornithine L-aspartate [LOLA], or rifaximin). The meta-analysis showed that probiotics significantly reversed MHE (OR = 3.95, p < 0.0001, 95% CI: 2.05 to 7.60) compared with placebo or no treatment. Probiotics also significantly reduced serum ammonia compared with placebo (pooled mean difference –25.94, p = 0.04, 95% CI: –50.21 to –1.66). However when compared to lactulose and LOLA, probiotics did not show a significant difference in reversal of MHE or reduction of serum ammonia levels.

Conclusions:
Probiotics were more effective in reversal of MHE and reduced serum ammonia levels in patients with MHE compared to placebo or no treatment, but not more effective than lactulose or LOLA.