Body Roundness Index and Waist-to-Height Ratio are Strongly Associated With Non-Alcoholic Fatty Liver Disease: A Population-Based Study.
BACKGROUND
A strong association between obesity and non-alcoholic fatty liver disease (NAFLD) has been reported.


OBJECTIVE
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.
Department of Social Medicine, Zanjan University of Medical Sciences, Zanjan, IR Iran.
Nima
N
Motamed
Gastrointestinal and Liver Disease Research Center (GILDRC), Tehran Firoozgar Hospital, Iran University of Medical Sciences, Tehran, IR Iran.
Behnam
B
Rabiee
Gastrointestinal and Liver Disease Research Center (GILDRC), Tehran Firoozgar Hospital, Iran University of Medical Sciences, Tehran, IR Iran.
Gholam Reza
GR
Hemasi
Gastrointestinal and Liver Disease Research Center (GILDRC), Tehran Firoozgar Hospital, Iran University of Medical Sciences, Tehran, IR Iran.
Hossein
H
Ajdarkosh
Gastrointestinal and Liver Disease Research Center (GILDRC), Tehran Firoozgar Hospital, Iran University of Medical Sciences, Tehran, IR Iran.
Mahmood Reza
MR
Khonsari
Gastrointestinal and Liver Disease Research Center (GILDRC), Tehran Firoozgar Hospital, Iran University of Medical Sciences, Tehran, IR Iran.
Mansooreh
M
Maadi
Department of Virology, Iran University of Medical Sciences, Tehran, IR Iran.
Hossein
H
Keyvani
Gastrointestinal and Liver Disease Research Center (GILDRC), Tehran Firoozgar Hospital, Iran University of Medical Sciences, Tehran, IR Iran.
Farhad
F
Zamani
Non-Alcoholic Fatty Liver Disease; Obesity; Waist-to-Height Ratio