The mediating role of insulin resistance in the association between inflammatory score and MAFLD: NHANES 2017–2018

Background

The association between inflammatory score, insulin resistance (IR), and metabolic-associated fatty liver disease (MAFLD) is inconclusive.

Objective

The objective of this study was to examine the relationship between the inflammatory score and MAFLD and investigate the potential mediating effect of IR (evaluated by triglyceride-glucose index) in this association.

Methods

Calculating inflammatory score was performed based on white blood cells and high-sensitivity C-reactive protein. The association between the inflammatory score and MAFLD was evaluated based on the weighted multifactor logistic regression model. Restricted cubic splines (RCS) were used to visualize the dose–response relationship between the inflammatory score and MAFLD. We also conducted a mediation analysis to assess the extent to which IR mediates this association.

Results

Among the 1090 participants, 563 were ultimately diagnosed with MAFLD. Multivariate logistic regression results indicated a close positive association between inflammatory score and MAFLD (odds ratio = 1.235, 95% confidence interval 1.069–1.427, p = .007). The RCS results indicated a linear dose–response relationship between the inflammatory score and the risk of MAFLD after adjusting for potential confounding factors. Furthermore, the mediation analysis results showed that IR partially mediated the association between the inflammatory score and MAFLD (percent mediation = 33%).

Conclusion

Our research results indicate that the inflammatory score is positively associated with the risk of MAFLD, and IR plays a partial mediating effect in this association.