Inverse association between serum iron and liver stiffness

Background: Liver fibrogenesis is a process of hepatic cell repairment. Hepatic fibrosis is the pathological status of liver health under different stress, including infection or inflammation. Iron is an essential micronutrition with the specific function of human cells, while excess iron may induce oxidative stress in cells and tissues. Aim: The liver is the main organ of iron storage. The study aimed to evaluate the relationship of serum iron with the hepatic stiffness measurement (liver stiffness measurement [LSM]). Methods: A total of 5521 adult participants aged 20 and over with recorded LSM and serum iron concentration from the U. S. National Health and Nutrition Examination Survey datasets (2017–2018) were enrolled in this study. The association between serum iron concentration and LSM is analyzed by multivariate linear regression models. Results: An increased serum iron concentration was significantly correlated with decreasing LSM in the adjusted model (β coefficient: –0.0005; 95% confidence interval: –0.001, –0.00008; P = 0.020). Moreover, the subgroup analysis also disclosed a negative association in nongeriatric adults. The serum ferritin concentration was positively associated with LSM. The quartile-based analysis found a significant inverse correlation between quartile serum iron concentration and the lowest serum iron concentration. Conclusion: Serum iron concentration and LSM was inversely associated. The assessment of iron biomarkers might be a part of evaluating liver health and chronic liver diseases. Decrease serum iron or increase ferritin implies a possible pro-inflammatory process in the liver, and within the normal range, higher serum iron levels and lower serum ferritin are considered to be a balance status of body iron homeostasis and reduced the risks of liver fibrosis.