Association of blood manganese levels with non-alcoholic fatty liver disease in NHANES 2017–2020: A retrospective cross-sectional study

Objective

This study investigates the link between blood manganese (Mn) levels and non-alcoholic fatty liver disease (NAFLD) in a U.S. adult population.

Background

The role of manganese in NAFLD remains poorly understood. However, the NHANES database offers valuable data on blood manganese levels and metabolic status for 6278 subjects in the United States, facilitating the study of this relationship.

Methods

To investigate the relationship between blood manganese (Mn) levels and NAFLD, we conducted a t-test to compare Mn levels between participants with and without NAFLD. Participants were categorized into quartiles based on their blood Mn levels. We then employed multiple logistic regression analysis and sensitivity analyses to further examine the Mn-NAFLD relationship.

Results

The NAFLD group had a significantly higher blood manganese level (10.0 ± 3.7 μg/L, P < 0.05) than the control group. Stratifying 6278 subjects by blood manganese quartiles showed increased NAFLD odds in higher quartiles (Q2-Q4) vs. Q1 (ORs: 1.49, 1.37, 1.49). The Mn-NAFLD relationship followed an inverted L-shaped curve, peaking at 8.52 μg/L.

Conclusions

Elevated levels of manganese in the blood have been shown to be associated with an increase in the risk of NAFLD, and blood manganese values can be utilized as a marker for assessing NAFLD.