Association between body roundness index and non-alcoholic fatty liver disease detected by Fibroscan in America.

Background: The prevalence of non-alcoholic fatty liver disease (NAFLD) and obesity is worldwide on the rise. Body roundness index (BRI), as a newly developed anthropometric indicator, has been recently reported to identify obesity. However, it is still unclear whether BRI is associated with the prevalence of NAFLD.

Methods: Data were from the National Health and Nutrition Examination Survey (NHANES) 2017-2018. NAFLD was diagnosed based on hepatic steatosis defined by CAP values ≥274 dB/m. Multivariable logistic regression analysis was performed to detect the association between BRI and the odds of NAFLD. Subgroup analysis stratified by age, gender, BMI, and race was further conducted. To explore the potential ability of BRI in predicting NAFLD, the area under the curve (AUC) of BRI was calculated by receiver operating characteristic (ROC) analysis.

Results: Among the 4467 study participants, 1718 (38.5%) were diagnosed with NAFLD. Compared to the non-NAFLD group, participants with NAFLD had a higher level of BRI. The positive associations between BRI and NAFLD were detected in all three models (mode 1: OR = 1.71, 95% CI: 1.65-1.78, p < 0.0001; mode 2: OR = 1.78, 95% CI: 1.71-1.86, p < 0.0001; mode3: OR = 1.23, 95% CI: 1.11-1.35, p < 0.0001). The positive association steadily existed in different subgroups after stratified by age, gender, and BMI. Moreover, the non-linear association between BRI and NAFLD was detected, presenting inverted U-shaped curves. Furthermore, BRI had a high predictive value (AUC = 0.807) in identifying NAFLD.

Conclusions: BRI was positively associated with the prevalence of NAFLD among individuals in America, regardless of age, gender, and BMI. Besides, BRI presented a high ability for identifying NAFLD.