Background: A strong association between obesity and non-alcoholic fatty liver disease (NAFLD) has been reported. Objectives: This study was conducted to evaluate if new obesity indices, including a body shape index (ABSI) and body roundness index (BRI), have stronger associations with NAFLD than waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR). Methods: In this cross-sectional study, we utilized the data of 4,872 participants aged 18 - 74 years from a cohort study conducted among 6,143 subjects in northern Iran. Logistic regression analysis was performed on NAFLD as the outcome and obesity measures (based on Z-score values) as potential predictors. Receiver operating characteristic (ROC) analyses were conducted, in which NAFLD was considered as a reference variable and obesity measures as classification variables. The discriminatory ability of the obesity measures was reported based on area-under-the-curves, and the related cut-off points of BRI and WHtR were determined using the Youden index (YI). Results: Based on our results, BRI (OR = 5.484 for men and OR = 3.482 for women) and WHtR (OR = 5.309 for men and OR = 3.854 for women) showed a higher association with NAFLD than ABSI (OR = 1.363 for men and OR = 1.003 for women) and WHR (OR = 3.123 for men and OR = 1.628 for women). The optimal cut-off points for BRI were 4.00 (sensitivity = 82.7%, specificity = 70.8%) for men and 5.00 (sensitivity = 83.3%, specificity = 71.7%) for women. The optimal cut-off points for WHtR were 0.533 (sensitivity = 82.7%, specificity = 70.8%) for men and 0.580 (sensitivity = 83.3%, specificity = 71.7%) for women. Conclusions: While BRI and WHtR have equally strong associations with NAFLD, ABSI and WHR have weaker associations with NAFLD than BRI and WHtR. Keywords: Non-Alcoholic Fatty Liver Disease; Obesity; Waist-to-Height Ratio

Background Visceral adiposity index (VAI) has been suggested as an index of visceral adiposity. This study was conducted to determine the discriminatory ability of VAI in diagnosis of metabolic syndrome (MetS). Methods and materials We used the data of 5 312 subjects aged 18–74 years of a cohort study conducted among 6 140 individuals aged 10–90 years in Amol, northern Iran. The city population was divided into 16 strata based on gender and age groups in 10-year intervals. The subjects were randomly selected from each stratum. MetS was defined based on National Cholesterol Education Program Adult Treatment Panel III (NCEP/ATPIII), American Heart Association/National Heart, Lung and Blood Institute (AHA/NHLBI) update of Adult Treatment Panel III (ATPIII), International Diabetes Federation (IDF) and joint interim statement (JIS) definitions. The discriminatory ability of VAI and other obesity measures were evaluated using receiver operating characteristic (ROC) curves. Results While waist circumference (WC) showed the highest discriminatory ability for MetS in IDF definition in men (AUC=0.899 [CI=0.888–0.910]), VAI had the greatest discriminatory ability according to other definitions in men and women. The related AUCs of VAI were 0.866 (95%CI: 0.850–0.881), 0.829 (95%CI: 0.813–0.846), 0.859 (95%CI: 0.844–0.873) and 0.876 (95%CI: 0.863–0.889) based on NCEP/ATPIII, AHA/NHLBI update of ATPIII, IDF and JIS definition in men, and also 0.888 (95%CI: 0.875–0.902), 0.894 (95%CI: 0.881–0.907), 0.883 (95%CI: 0.869–0.897) and 0.879 (95%CI: 0.864–0.894) in women, respectively. Conclusion VAI showed an excellent discriminatory ability in diagnosis of MetS. Considering its relatively simple calculation, this index could be suggested as a reliable tool in medical practice.