Meta-analysis of the effect and safety of berberine in the treatment of type 2 diabetes mellitus, hyperlipemia and hypertension

Ethnopharmacological relevance: Berberine, extracted from Coptis Root and Phellodendron Chinese, has been frequently used for the adjuvant treatment of type 2 diabetes mellitus, hyperlipidemia, and hypertension in China. Safety and efficacy studies in terms of evidence-based medical practice have become more prevalent in application to Chinese Herbal Medicine. It is necessary to assess the efficacy and safety of berberine in the treatment of type 2 diabetes mellitus, hyperlipidemia and hypertension by conducting a systematic review and meta-analysis of available clinical data.

Materials and methods: We searched the English databases PubMed, ScienceDirect, Cochrane library, EMbase, etc., and Chinese databases including China biomedical literature database (CBM), Chinese Technology Journal Full-text Database, Chinese journal full text database (CNKI), and Wanfang digital periodical full text database. Relevant studies were selected based on the inclusion and exclusion criteria. Meta-analysis was performed with RevMan5.0 software after data extraction and the quality of studies assessment.

Results: Twenty-seven randomized controlled clinical trials were included with 2569 patients. There are seven subgroups in our meta-analysis: berberine versus placebo or berberine with intensive lifestyle intervention versus intensive lifestyle intervention alone; berberine combined with oral hypoglycemic versus hypoglycemic alone; berberine versus oral hypoglycemic; berberine combined with oral lipid lowering drugs versus lipid lowering drugs alone; berberine versus oral lipid lowering drugs; berberine combined with oral hypotensor versus hypotensive medications; berberine versus oral hypotensive medications. In the treatment of type 2 diabetes mellitus, we found that berberine with lifestyle intervention tended to lower the level of FPG, PPG and HbA1c than lifestyle intervention alone or placebo; the same as berberine combined with oral hypoglycaemics to the same hypoglycaemics; but there was no statistical significance between berberine and oral hypoglycaemics. As for the treatment of hyperlipidemia, berberine with lifestyle intervention was better than lifestyle intervention, berberine with oral lipid lowering drugs was better than lipid lowering drugs alone in reducing the level of TC and LDL-C, and raising the level of HDL-C. In the comparative study between berberine and oral lipid lowering drugs, there was no statistical significance in reducing the level of TC and LDL-C, but berberine shows better effect in lowering the level of TG and raising the level of HDL-C. In the treatment of hypertension, berberine with lifestyle intervention tended to lower the level of blood pressure more than the lifestyle intervention alone or placebo did; The same occurred when berberine combined with oral hypotensor was compared to the same hypotensor. Notably, no serious adverse reaction was reported in the 27 experiments.

Conclusion: This study indicates that berberine has comparable therapeutic effect on type 2 DM, hyperlipidemia and hypertension with no serious side effect. Considering the relatively low cost compared with other first-line medicine and treatment, berberine might be a good alternative for low socioeconomic status patients to treat type 2 DM, hyperlipidemia, hypertension over long time period. Due to overall limited quality of the included studies, the therapeutic benefit of berberine can be substantiated to a limited degree. Better methodological quality, large controlled trials using standardized preparation are expected to further quantify the therapeutic effect of berberine.