Increased serum/plasma fibroblast growth factor 21 in type 2 diabetes mellitus: a systematic review and meta-analysis.

OBJECTIVES: Fibroblast growth factor-21 (FGF-21) plays an important role in glucose and lipid metabolism. This study aims to systemically review the evidence regarding the relationship between the FGF-21 levels and type 2 diabetes mellitus (T2DM), as well as the related influential factors.
METHODS: Research related to plasma/serum FGF-21 levels in patients with T2DM and healthy controls were searched in PubMed, EMBASE and The Cochrane Library databases (up to 31 March 2017). Pooled standard mean difference (SMD) with 95% CI was calculated by fixed-effect or random-effect model analysis. Heterogeneity test was performed by the Q-statistic and quantified using I 2, and publication bias was evaluated using a funnel plot and Egger's linear regression test.
RESULTS: In total, 317 articles were obtained after searching databases, and 11 studies with 866 patients with T2DM and 629 controls were finally included. Meta-analysis revealed that, compared with the control group, the T2DM group had a significantly higher plasma/serum FGF-21 level (p < 0.001), with the SMD of 1.34% and 95% CI (0.70 to 1.98). Meta-regression analysis and subgroup analyses suggested that body mass index (BMI), triglycerides (TG) and total cholesterol (TC) were likely related to the observed FGF-21 differences between two groups.
CONCLUSIONS: Overall, our study suggests that patients with T2DM have significantly higher plasma/serum FGF-21 levels, and the FGF-21 levels were influenced by BMI, TC and TG. © Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.