Effectiveness of Chinese herbal medicine in treating liver fibrosis: a systematic review and meta-analysis of randomized controlled trials

Abstract

Background: The studies on the effectiveness of Chinese herbal medicines (CHM) in treating liver fibrosis (LF) were not consistent. This study aims to systematically review the effectiveness of CHM on treating LF patients.

Methods: Databases including MEDLINE, AMED, EMBASE, The Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, TCMOnline, Chinese Biomedical Literature Database, and Chinese Medical Current Contents were searched up to March 2011. Randomized controlled trials (RCTs) involving LF patients receiving CHM, Western medicine, combined CHM and Western medicine compared with placebo, Western medicine or no intervention were included. LF markers including serum hyaluronic acid (HA), laminin (LN), procollagen type III (PC-III), type IV collagen (IV-C), matrix metalloproteinase (MMP), and tissue inhibitors of metalloproteinase (TIMP) were measured as primary outcomes. Liver biochemistry, including alanine aminotransferase (ALT) and aspartarte aminotransferase (AST), and improvement of related clinical symptoms were measured as secondary outcomes. Risk of bias of allocation sequence, allocation concealment, blinding, incomplete outcome data, selective outcome reporting, and other biases were assessed.

Results: Twenty-three RCTs with 2123 participants were analyzed in subgroups of types of comparison and study quality. Fifteen studies were graded as good quality. CHM alone and combined with Western medicine showed significant improvements in HA, LN, PC-III and IV-C compared with Western medicine alone. However, there were no significant differences observed between CHM and placebo treatments.

Conclusion: The current inconclusive results in determining the effectiveness of CHM treatment on LF, due to the poor methodological quality and high heterogeneity of the studies, suggests that large RCTs using standardized Chinese medicine syndrome diagnosis and CHM formulae with longer follow-up are required for further evaluation.

Figure 1

Flow diagram of study selection process.

Figure 2

Forest plot of studies comparing Chinese herbal medicine and western medicine, examining the effect on liver fibrosis markers (including HA, LN, PC-III and IV-C). (A) HA. (B) LN. (C) PC-III. (D) IV-C. Vertical line represents no effect point; CI, confidence interval; HA, hyaluronic acid; LN, laminin; PC-III, procollagen type III; IV-C, type IV collagen.

Figure 3

Forest plot of studies comparing Chinese herbal medicine and placebo medicine, examining the effect on liver fibrosis markers (including HA, LN, PC-III and IV-C). (A) HA. (B) LN. (C) PC-III. (D) IV-C.

Figure 4

Forest plot of studies comparing combined medicine and western medicine, examining the effect on liver fibrosis markers (including HA, LN, PC-III and IV-C). (A). HA. (B) LN. (C) PC-III. (D) IV-C.