Mediating effect of fasting insulin on the association between body mass index and nonalcoholic fatty liver disease

Objective: To explore the mediating effect of fasting insulin (FINS) on the association between body mass index and nonalcoholic fatty liver disease (NAFLD).Methods: A total of 389 NAFLD patients and 1, 530 healthy subjects were enrolled in this study.Multivariate logistic regression analysis was applied to evaluate the associations of body mass index and FINS with NAFLD.Multivariate linear regression analysis was applied to estimate the association between body mass index and FINS.The Bootstrap method was used to analyze the mediating effect of FINS on the association between body mass index and NAFLD.Results: After adjusting for relevant confounding factors, the associations of body mass index and FINS with the risk of NAFLD were statistically significant (OR=1.434, 95% CI:1.352-1.521, P＜0.001; OR_FINS=1.048, 95%CI:1.026-1.071, P＜0.001, respectively).The association between increased body mass index and increased FINS level was statistically significant(B=0.723, 95%CI:0.618-0.828, P＜0.001).FINS had a mediating effect(effect value 0.034, 95% CI: 0.015-0.059) on the association between body mass index and NAFLD, and the mediating effect accounted for 8.61%.Conclusion: FINS plays a partial mediating role on the association between body mass index and NAFLD.