# Magnetic resonance evaluation of three-dimensional liver fat fraction by hepatitis C status and associations with inflammatory cytokines

## TL;DR

This study uses MRI to find that chronic hepatitis C is linked to higher liver fat and altered cytokine levels, but these cytokines don't directly affect fat accumulation.

## Contribution

The study introduces MRI-based three-dimensional liver fat fraction evaluation in chronic HCV patients and its cytokine associations.

## Key findings

- Chronic HCV is associated with a 2.28% higher median liver fat fraction compared to non-HCV participants.
- HCV is linked to elevated TNF-α and IL-18 levels but not directly to liver fat fraction.
- IGF-1 levels are lower in HCV patients, but no cytokine or IGF-1 was associated with liver fat fraction.

## Abstract

Chronic hepatitis C virus (HCV) infection may influence cytokine and insulin-like growth factor (IGF-1) levels, which could contribute to increased hepatic steatosis. We utilized MRI to compare three-dimensional volumetric liver fat fraction by chronic HCV status and evaluated associations between liver fat fraction and inflammatory cytokines and IGF-1.

Participants with untreated, non-genotype 3 chronic HCV and participants without HCV were enrolled between 2019−2022 and underwent MRI to quantify three-dimensional volumetric liver fat fraction. Interleukin (IL)-6, IL-18, tumor necrosis factor (TNF)-α, and IGF-1 were also measured. Multivariable linear regression was used to determine associations between liver fat fraction, chronic HCV, and cytokine and IGF-1 levels.

Among 54 participants with HCV and 54 without HCV, median volumetric liver fat fraction was 12.4% (IQR: 9.3, 18.0%) and 10.9% (IQR: 8.7, 13.3%), respectively. After adjustment for age, sex, and body mass index, mean liver fat fraction was 2.28% (95% CI: 0.55, 4.02%) higher in participants with HCV. HCV was associated with higher mean log TNF-α (0.11 [95% CI: 0.06, 0.16]) and IL-18 (0.14 [95% CI: 0.05, 0.24]), but lower mean log IGF-1 (−0.18 [95% CI: −0.26, −0.11]) when compared to those without HCV. IL-6, IL-18, TNF-α, and IGF-1 were not associated with liver fat fraction.

Chronic HCV is associated with higher volumetric liver fat fraction by MRI. TNF-α and IL-18 levels were higher with chronic HCV but were not associated with liver fat fraction. Further research is needed to identify alternative mechanisms that potentiate liver fat deposition in chronic HCV.