Probiotics, prebiotics, and synbiotics for the improvement of metabolic profiles in patients with chronic kidney disease: A systematic review and meta-analysis of randomized controlled trials

Abstract

This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to quantify the effects of probiotic, prebiotic, and synbiotic supplementation on biomarkers of inflammation and oxidative stress, as well as lipid profiles among patients with chronic kidney disease (CKD). Electronic databases, including PubMed, the Cochrane Database, and the Web of Science were searched from January 1, 2000, to May 15, 2019. All RCTs that investigated the effect of prebiotics, probiotics, and synbiotics on a circulating (serum and plasma) inflammatory marker (C-reactive protein [CRP]), oxidative stress indicators (malondialdehyde [MDA], glutathione [GSH], and total anti-oxidant capacity [TAC]); and lipid profiles (total cholesterol [TC], triglycerides [TG], low-density lipoprotein cholesterol [LDL-c], and high-density lipoprotein cholesterol [HDL-c]) among patients with CKD were included. Data were pooled and expressed as a standardized mean difference (SMD) with a 95% confidence interval (CI). The protocol for this meta-analysis is registered with PROSPERO; No. CRD42019139090. Thirteen trials that included 671 patients were identified for analysis. The methodological quality varied across studies. Meta-analysis indicated that microbial therapies significantly reduced CRP (SMD, −0.75; 95% CI, −1.03 to −0.47; p = 0.000), MDA (SMD, −1.06; 95% CI, −1.59 to −0.52; p = 0.000), TC (SMD, −0.33; 95% CI, −0.52 to −0.13; p = 0.000), and LDL-c (SMD, −0.44; 95% CI, −0.86 to −0.02; p = 0.000) levels; they also increased the GSH (SMD, 0.44; 95% CI, 0.25 to 0.65; p = 0.000), TAC (SMD, 0.61; 95% CI, 0.07 to 1.15; p = 0.000), and HDL-c (SMD, 0.45; 95% CI, 0.03 to 0.87; p = 0.000) levels in CKD patients, as compared to the placebo groups; however, there was no statistically significant TG concentration among patients with CKD. Subgroup analyses showed that other key factors, such as the duration of intervention, participants’ baseline body mass index (BMI), type of intervention, and age, had an effect of microbial therapies on outcomes. This meta-analysis supports the potential use of probiotic, prebiotic, and synbiotic supplements in the improvement of established biomarkers of inflammation and oxidative stress, as well as lipid profiles among patients with CKD, which are well-known cardiovascular risk factors. Further research into these interventions should consider the limitations of our study to explore the effect of long-term administration of these supplements in the CKD population.

Keywords:

• Chronic kidney disease
• probiotic
• prebiotic
• synbiotic
• inflammation
• oxidative stress
• lipid profile
• meta-analysis
• randomized controlled trials

Conflicts of interest

No potential conflict of interest was declared by the authors.

Author contributions

H.J.Z. and Y.X.W. designed the study. H.J.Z. and L.S.W. searched databases, performed the selection of studies. H.J.Z., L.S.W. and J.G., analyzed the data and wrote the manuscript. W.J.L. and Y.X.W. critically evaluated the review and commented on it. Q.H.W., Y.H.W., W.J.H., F.Z., and W.T.Z. contributed in revised version. The final version was confirmed by all authors for submission.

Additional information

Funding

This study was supported by National Natural Science Foundation of China (Grant Nos. 81774298) and Fundamental Research Funds for the Central Universities (Grant Nos. 2019-JYB-JS-043), but this study did not receive any public funding from commercial.