Association of circulating vaspin levels and patients with metabolic-associated fatty liver disease: a systematic review and meta-analysis

Background The incidence rate of metabolic-associated fatty liver disease (MAFLD) is increasing annually; however, there are still no effective methods for establishing an early diagnosis and conducting real-time tracing. Vaspin can affect the metabolic processes in the body, and it is closely associated with many metabolic diseases. Many previous studies have speculated on the association between vaspin and MAFLD, but the results of these studies have not been conclusive. This meta-analysis examined the differences in circulating vaspin levels between patients with MAFLD and healthy individuals. Methods Six databases and other sources were searched with free terms and Medical Subject Headings terms, and a total of 13 articles were included (900 cases and 669 controls). RevMan 5.3 and Stata 16 were used for analysis. The standardised mean difference (SMD) and 95% confidence interval (CI) were used to assess the overall outcomes. Cohen's kappa coefficient was applied to examine the differences between the two authors in the selection of studies and in the evaluation of the quality of evidence for the studies. Results The results demonstrated that there was no significant difference in the circulating vaspin levels between the MAFLD group and healthy group (SMD = 0.46, 95% CI: [- 0.12, 1.04]). The subgroup analysis suggested that area and body mass index (BMI) may be the sources of heterogeneity, and the results of univariate meta-regression analysis were consistent with those of the subgroup analysis (P = 0.005 and P < 0.001, respectively). Furthermore, BMI may better explain the source of heterogeneity (P = 0.032) in the multivariate meta-regression analysis. Conclusion In summary, no significant correlation was observed between the circulating vaspin levels and MAFLD. BMI may be an important factor affecting this correlation, which may provide a reference for further studies on mechanism and diagnosis of MAFLD. Keywords: Metabolic-associated fatty liver disease, Nonalcoholic fatty liver disease, Nonalcoholic steatohepatitis, Vaspin, Meta-analysis