Risk factors associated with non-alcoholic fatty liver disease in Chinese patients and the role of tumor necrosis factor-alpha.

Background/aims: Tumor necrosis factor-alpha (TNFalpha) has been reported to be associated with insulin resistance and induce inflammatory cytokines formation. Previous studies in human and animals showed inhibition of TNF-alpha improved severity of non-alcoholic fatty liver disease (NAFLD). The aims of this study were to measure plasma levels of TNFalpha in NAFLD and healthy subjects and investigate potential risk factors.

Methodology: A total of 144 patients (90 NAFLD, 50 controls) were enrolled. Clinical and laboratory data of each patient were collected. Plasma levels of TNF-alpha were measured with a commercially available solid phase sandwich enzyme-linked immunosorbent assay (R&D systems, USA). The lower detection limit of this assay was 0.12 pg/mL.

Results: Multivariate analyses showed elevated triglyceride (odds ratio: 7.30, p<0.001) and BMI >25 kg/m2 (odds ratio: 3.57, p<0.005) were the two factors associated with NAFLD. Mean plasma level of TNF-alpha was significantly higher in NAFLD patients with abnormal ALT than controls (2.63+/-0.44 pg/mL vs. 1.56+/-0.10 pg/mL, p=0.016). Modest correlations were noted between plasma levels of TNF-alpha with ALT (r=0.25, p<0.005) and triglyceride (r=0.40, p<0.001).

Conclusions: TNF-alpha may participate in the pathogenesis of NAFLD. Inhibition of TNF-alpha activity by drugs or antibodies may be a potential approach to treat NAFLD patients.