Fibroblast growth factor 21 may be a strong biomarker for renal outcomes: a meta-analysis.

Background: Fibroblast growth factor 21 (FGF21) is deemed to play an important role in kidney outcomes, while the association between FGF21 and various kidney diseases remains largely unclear and inconsistent. Therefore, we conducted this meta-analysis to find out the role of FGF21 in various renal diseases.

Methods: The outcome indicator of our study was assessed by the pooled standard mean difference (SMD) with 95% confidence intervals (CIs) which were calculated by random-effect model analysis. The risk of bias was assessed by Non-Randomized Studies of Interventions (ROBINS-I) tool. Funnel plot combined with Egger's and Begg's tests was performed to estimate the publication bias that existed in the study.

Results: A total of 28 eligible studies with 19348 participants were included in our research. The agreement between authors reached a kappa-value of 0.88. Overall, the serum FGF21 level was strongly higher in CKD patients (SMD = 0.97 (ng/L); 95% CI, 0.70-1.24 (ng/L)) and the renal outcomes in T2DM patients (SMD = 0.54 (ng/L); 95% CI, 0.39-0.70 (ng/L)) compared with the control group. Consistent with this, the incidence of CKD (OR = 2.56; 95% CI, 1.72-3.81) and the incidence of renal outcomes (OR = 1.63; 95% CI, 1.31-2.01) in T2DM patients was significantly higher in the patients with high FGF21 concentration, indicating that high serum FGF21 level may predict the incidence of CKD and the renal outcomes in T2DM patients.

Conclusion: Serum FGF21 may be one of the strong predictors for various kidney diseases including the progression of CKD and the hard renal outcomes in type 2 diabetes patients, but more large-scale clinical research are needed to confirm this finding.