Xiaoyao Powder in the treatment of non-alcoholic fatty liver disease: A systematic review and meta-analysis

Abstract

Ethnopharmacological relevance: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver disease worldwide with alarming prevalence. Due to its complex pathogeneses and considerable individual heterogeneity in disease, there is no specific medication to NAFLD safely and effectively. Therefore, there is a great need to explore complementary and alternative therapies. Xiaoyao Powder (XYP), a classic Chinese formula, has been tremendously applied to gastrointestinal diseases, especially non-alcoholic fatty liver disease. However, the efficacy and safety of XYP have not been fully assessed.

Aim of the study: To assess the effectiveness and safety of XYP for NAFLD.

Materials and methods: The assigned registration number on the PROSPERO platform of this meta-analysis is CRD42020192154, and we strictly followed the protocol. We searched eight primary databases from their inception to June 2020. Two authors independently identified random controlled trials (RCTs) of XYP for NAFLD and evaluated the quality of the retrieved articles by Cochrane accessing risk bias tool. At least one of the following indices was thoroughly documented for outcome measurement: total effective rate, total cholesterol (TC), triglyceride (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutamyl transpeptidase (GGT), body mass index (BMI), and adiponectin. We calculated risk ratio (RR) and mean difference (MD) for dichotomous data and continuous variables with a 95% confidence interval (CI). R 4.0.5 software was employed for data synthesis.

Results: Consequently, we identified 12 studies with 1012 participants. XYP, whether individually or combined with essential treatment, ameliorated NAFLD regardless of the course of the disease or curative duration. This benefit was mainly driven by regulating levels of serum markers, involving TC, TG, ALT, AST, GGT, and adiponectin. Three studies where statins were concerned about drug safety reported several adverse events with clinical symptoms, varying from flatulence, constipation, and diarrhea to rash, whereas others did not.

Conclusion: Our findings provided evidence that XYP is a therapeutic option to treat NAFLD effectively and safely. Notwithstanding, a precise and comprehensive conclusion calls for RCTs on a larger scale with more rigorous designs considering the inferior methodological quality and limited retrieved articles.

Keywords: Meta-analysis; Non-alcoholic fatty liver disease; Systematic review; Traditional Chinese medicine; Xiaoyao Powder.