Efficacy and safety of omega-3 fatty acids on liver-related outcomes in patients with nonalcoholic fatty liver disease A protocol for a systematic review and meta-analysis

Background: Non-alcoholic fatty liver disease (NAFLD), especially non-alcoholic steatohepatitis, which is considered as the hepatic manifestation of metabolic syndrome, has a great prevalence all over the world. New drugs are urgently needed for the treatment of NAFLD. This review will be to assess the efficacy and safety of omega-3 polyunsaturated fatty acids (n-3 PUFAs) on liver-related outcomes (liver histology and liver enzymes) in patients with NAFLD. Methods: We will search 5 databases for relative studies: Medline, the Cochrane Library, EMBASE, Web of Science, and ClinicalTrials.gov and identified all reports of randomized controlled trials published prior to July 2020. Two authors will independently scan the articles searched, extract the data from articles included, and assess the risk of bias by Cochrane tool of risk of bias. Disagreements will be resolved by discussion among authors. All analysis will be performed based on the Cochrane Handbook for Systematic Reviews of Interventions. Fixed-effects model or random-effects model will be used to calculate pooled estimates of weighted mean difference with 95% confidence intervals. Results: This systematic review aims to examine the effect of n-3 PUFAs on liver histology and liver enzymes in patients with NAFLD. Conclusions: These findings will provide guidance to clinicians and patients on the use of n-3 PUFAs for NAFLD. Ethics and dissemination: This study is a protocol for a systematic review of n-3 PUFAs as a treatment of NAFLD patients. This review will be published in a journal and disseminated in print by peer-review.