Association Between HLA Polymorphisms and Non-Alcoholic Fatty Liver Disease in Patients with Rheumatoid Arthritis: An...

This observational study investigated associations between human leukocyte antigen (HLA) polymorphisms and imaging-defined hepatic steatosis (non-alcoholic fatty liver disease-NAFLD) and liver fibrosis in patients with rheumatoid arthritis (RA).

Steatosis was assessed by transient elastography (FibroScan) and defined as controlled attenuation parameter (CAP) ≥ 275 dB/m; fibrosis was defined as liver stiffness measurement ≥ 8 kPa. We tested 11 frequent HLA alleles (HLA-A*02, HLA-B*07, HLA-B*08, HLA-B*27, HLA-B*35, HLA-B*44, HLA-B*51, HLA-DRB1*11, HLA-DRB1*14, HLA-DRB1*15, and HLA-DRB1*16). Associations were evaluated using multivariable logistic regression (individual and omnibus models) adjusted for age, body mass index (BMI), triglycerides, and glucose.

A total of 176 patients with rheumatoid arthritis were enrolled. NAFLD/steatosis was present in 35.2% of patients (n = 62), and fibrosis in 10.8% (n = 19). No HLA allele was significantly associated with steatosis or fibrosis after correction for multiple testing. BMI and triglycerides were independently associated with steatosis (BMI OR 1.22, 95% CI 1.12-1.34; triglycerides OR 1.48, 95% CI 1.04-2.18). For fibrosis, HLA-DRB1*15 showed the strongest trend-level association (OR ~2.6-2.9) but did not remain significant after correcting for multiple testing.

In this RA cohort, metabolic factors (particularly BMI and triglycerides) were the dominant predictors of CAP-defined steatosis. No robust association between the tested HLA markers and steatosis or fibrosis was identified. Trend-level signals-most notably HLA-DRB1*15 for fibrosis-should be considered hypothesis-generating and warrant replication in larger, adequately powered cohorts.