Table 2: Characteristics of RCTs using herbal medicine in the treatment of metabolic syndrome.

Author, year, countrySample size (I/C)AgeSex (M/F)Inclusion criteria of MetSChinese pattern identificationInterventionControlPeriodOutcomesMain conclusion

Agrawal et al., 2008, India [13]94/89I: 51.85 ± 11.8 C: 52.81 ± 10.3103/80NCEP-ATP guideline (2002)NDDia-No,
1 tab, bid
Placebo,
1 tab, bid
3 mWC, FPG, HbA1c, TC, TG, HDL-C, VLDL, LDL-C, SBP, DBP, urea, creatinine, bilirubin, GOT, GPTDia-No is safe and effective drug in the management of MetS.

Chen et al., 2014, China [14]22/21I: 48.73 ± 9.4
C: 48.90 ± 8.9
28/15China Dyslipidemia Prevention guideline (2007)NDYiqi Huaju FormulaPlacebo, bid12 wBMI, body weight, WC, HC, WHR, FPG, HbA1c, FPI, 2 hPG, HOMA-IR, TC, TG, HDL-C, LDL-C, 24 hBP, dBP, nBP, 24 hBPv, dBPv, nBPv, 24 hBPp, dBPp, nBPpYiqi Huaju Formula combining with diet-control and exercise has effect on reducing blood pressure.

Zhang et al., 2014, China [15]56/5261.5 (37~80)59/49IDF
guideline (2005)
Phlegm-Dampness TypeDaotan decoctionNo treatment4 wBMI, WC, TG, HDL-C, FPG, SBP, DBPDaotan decoction can ameliorate the blood lipid and blood pressure of MetS of phlegm-dampness constitution.

Xu et al., 2014, China [16]83/69I: 51.75 ± 10.1
C: 52.30 ± 14.3
70/82IDF
guideline (2005)
NDGegen shanzha decoctionNo treatment6 mBMI, body weight, WC, AC, HC, WHR, SFA, VFA, FPG, FINS, HOMA-IR, TC, TG, HDL-C, LDL-C, SBP, DBP, SF-36Gegen Shanzha decoction combining with TCM physique recuperation is effective for MetS.

Li, 2014, China [17]32/30NRNRChinese Diabetes Society criteria (2004)Blood-Stasis TypeXuefu zhuyu decoction, bidNo treatment4 wBlood stasis symptomsXuefu Zhuyu decoction has clinical efficacy for MetS of Blood-Stasis Type.

Wang et al., 2005, China [18]30/30I: 49.6 ± 7.9
C: 50.6 ± 7.6
27/33American Diabetes Association guideline (1997)Heart-Liver Stagnated Heat TypeQinggan Jiangtang,
3 tabs, bid
Glucophage
(metformin),
3 tabs, bid
2 mFPG, 2 hPG, HbA1c, TC, TG, HDL-C, LDL-C, SBP, DBP, FINS, PINS, F-CP, P-CP, HOMA-IR, HOMA-β, FFA,Qinggan Jiangtang tablet has effects on reducing blood glucose, blood lipids, blood pressure, and insulin resistance.

Liu et al., 2008, China [19]30/3030–60NRIDF
guideline (2005)
Exuberance of Phlegm-Dampness TypeModified Banxia Baizhu Tianma decoction,
120 mL, bid
Metformin,
0.25 mg, tid
6 wWC, BMI, FPG, 2 hPG, FINS, ISI, TC, TG, HDL-C, LDL-C, ApoA1, ApoB, SBP, DBP, effective rate, Chinese symptomsModified Banxia Baizhu Tianma Decoction has effects on treating MetS of Exuberance of Phlegm-Dampness Type.

Zhang et al., 2010, China [20]50/50I: 52.61 ± 5.4
C: 51.10 ± 12.2
80/20Chinese Diabetes Society criteria (2004)Flaming-Up of Fire of the Liver TypePinggan Jiangya pill, 6 g, tidNifedipine,
10 mg, tid
1 mBMI, body weight, WC, SBP, DBPPinggan Jiangya pill has effects on decreasing blood pressure and weight of MetS of Flaming-Up of Fire of the Liver Type.

Guan et al., 2012, China [21]36/3247.2 ± 15.439/29AACE clinical criteria (2003)NDHuanglian Wendan decoctionMetformin,
0.25 mg, bid
8 wBMI, FPG, TC, TG, HDL-C, LDL-C, SBP, DBPHuanglian Wendan decoction is the same as metformin in reducing weight and blood sugar but better in decreasing blood lipids and blood pressure.

Dong, 2012, China [22]58/48I: 24~78
C: 21~73
44/62NCEP ATP guideline (2002)NDXueguan Ruanhua decoction (1 m) Xueguan Ruanhua pill (2 m)① DM: metformin or rosiglitazone
② HL: simvastatin or fenofibric acid
③ HTN: captopril or nifedipine
3 mFPG, TG, HDL-C, SBP, DBP, effective rateXueguan Ruanhua decoction has effects on the treatment of MetS.

Cui and Wie, 2014, China [23]60/60I: 51.3 ± 6.0
C: 52.3 ± 5.4
69/51Chinese Diabetes Society criteria (2004)NDShengjiangtongmai powder,
300 mL, bid
① Metformin, 0.25 mg, bid
② Simvastatin, 10 mg, qd
③ Enalapril,
10 mg, qd
2 mBMI, SBP, DBP, TC, TG, FPG, effective rateShengjiangtongmai powder can effectively improve blood glucose, blood lipid, blood pressure, and obesity.

Danyang Zhao and Danun Zhao, 2015, China [24]40/40I: 48.7 ± 12.5
C: 47.6 ± 12.6
NRIDF guideline (2005)Spleen Deficiency and Stagnation of Dampness TypeShenling Jianpihuashi decoction, bid① DM: metformin, 500 mg, tid
② HTN: losartan, 50 mg, qd
12 wWC, BMI, FPG, 2 hPG, HbA1c, TC, TG, HDL-C, LDL-C, SBP, DBP, HOMA-IR, effective rateShenling Jianpihuashi decoction can effectively improve MetS of Spleen Deficiency and Stagnation of Dampness type.

I: intervention group; C: control group; M: male; F: female; NR: not reported; MetS: metabolic syndrome; DM: diabetes mellitus; HTN: hypertension; HL: hyperlipidemia; WC: waist circumference; FPG: fasting plasma glucose; TC: total cholesterol; HDL-C: high density lipoprotein cholesterol; VLDL: very low density lipoprotein; LDL-C: low density lipoprotein cholesterol; SBP: systolic blood pressure; DBP: diastolic blood pressure; GOT: glutamic oxaloacetic transaminase; GPT: glutamic-pyruvic transaminase; BMI: body mass index; HC: hip circumference; WHR: waist hip ratio; FPI: fasting plasma insulin; 2hPG: 2-hour postprandial glucose; TG: triglycerides; AC: arm circumference; SFA: subcutaneous fat area; VFA: visceral fat area; FINS: fasting serum insulin; PINS: postprandial serum insulin; F-CP: fasting serum C-peptide; P-CP: postprandial serum C-peptide; FFA: free fatty acids; ISI: insulin sensitivity index.