title: Effects of probiotics supplement in patients with type 2 diabetes mellitus: A meta-analysis of randomized trials.
abstract: OBJECTIVE
  To objectively evaluate the effects of probiotics supplement on glycemic control and lipid metabolism in patients with type 2 diabetes mellitus (T2DM).
  
  
  METHODS
  The randomized controlled trials (RCTs) with regard to the probiotics or synbiotics for the treatment of T2DM were collected through retrieving 5 databases from their establishment to March 2016. After study selection, quality assessment and data extraction were performed by 2 authors independently; and STATA software was used for statistical analysis. The level of evidence was evaluated by applying the GRADE system.
  
  
  RESULTS
  Twelve RCTs involving 770 participants were enrolled. The results of the meta-analysis showed that probiotics could significantly reduce fasting blood glucose by -11.27mg/dL (95% CI -21.76 to -0.79; P<.001) and serum insulin concentration by -2.36μU/mL (95% CI -4.01 to -0.72; P=.005), but with no significant reduction on HbA1c(-0.19%; 95% CI -0.49 to 0.12; P=.23). Probiotics could significantly reduce HOMA-IR of T2DM patients (-1.05; 95% CI -1.52 to -0.59; P<.001). Nevertheless, the effect on QUICKI was negligible (0.00; 95% CI -0.00 to 0.01; P=.27). Results also confirmed the significant lowering effect of probiotics on total cholesterol (-8.49mg/dL; 95% CI -15.24 to -1.73; P=.014) and triglycerides (TG; -23.66mg/dL; 95% CI -40.26 to -7.05; P<.001), as well as the elevating effect on HDL-c (3.92mg/dL; 95% CI 2.14 to5.7; P<.01). However, there was no significant change on LDL-c (-0.84mg/dL; 95% CI -5.84 to 4.17; P=.75). Subgroup analysis was conducted for 2 outcomes, that is, serum insulin concentration and TG, whose heterogeneity was too high. The results showed multiple species of probiotics had stronger reduction effect on serum insulin concentration (-3.32μU/mL; 95% CI -5.89 to-0.75; P=.001) and TG (-25.94mg/dL; 95% CI -65.33 to 13.44; P<.001). In addition, it also suggested that only the duration of treatment for≥8 weeks could significantly reduce TG by -24.47mg/dL (95% CI -40.15 to -8.78; P=.001). The duration of treatment for<8 weeks didn't result in significant reduction on TG (-4.31mg/dL; 95% CI -37.69 to 29.06; P=.8). Finally, all the evidences were at moderate and low levels according to the GRADE system.
  
  
  CONCLUSIONS
  As a kind of the potential biotherapeutics in the management of T2DM, probiotics can improve glucose control and lipid metabolism.
authors.affiliation: Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Yi-Meng
authors.initials: YM
authors.lastname: Hu
authors.affiliation: Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhou
authors.affiliation: Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China. Electronic address: xycc567@126.com.
authors.forename: Yan-Cheng
authors.initials: YC
authors.lastname: Xu
mesh_terms: D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000628:therapy*; D006801:Humans; D050356:Lipid Metabolism; D019936:Probiotics / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D014280:Triglycerides; D002784:Cholesterol
keywords: Diabetes mellitus tipo 2; Meta-analysis; Metaanálisis; Probiotics; Probióticos; Type 2 diabetes mellitus