Research article

The Fatty Liver Index: a simple and accurate predictor of hepatic steatosis in the general population

Giorgio Bedogni¹ , Stefano Bellentani² , Lucia Miglioli² , Flora Masutti¹ , Marilena Passalacqua² , Anna Castiglione¹ and Claudio Tiribelli¹

¹Centro Studi Fegato (Liver Research Center), AREA Science Park, Basovizza, Trieste, and Department of Biochemistry, Biophysics and Macromolecular Chemistry, University of Trieste, Trieste, Italy

²Nutrition and Liver Center, AUSL Modena, Carpi Hospital, Carpi, Modena, Italy

author email corresponding author email

BMC Gastroenterology 2006, 6:33doi:10.1186/1471-230X-6-33

Published:	2 November 2006

Abstract

Background

Fatty liver (FL) is the most frequent liver disease in Western countries. We used data from the Dionysos Nutrition & Liver Study to develop a simple algorithm for the prediction of FL in the general population.

Methods

216 subjects with and 280 without suspected liver disease were studied. FL was diagnosed by ultrasonography and alcohol intake was assessed using a 7-day diary. Bootstrapped stepwise logistic regression was used to identify potential predictors of FL among 13 variables of interest [gender, age, ethanol intake, alanine transaminase, aspartate transaminase, gamma-glutamyl-transferase (GGT), body mass index (BMI), waist circumference, sum of 4 skinfolds, glucose, insulin, triglycerides, and cholesterol]. Potential predictors were entered into stepwise logistic regression models with the aim of obtaining the most simple and accurate algorithm for the prediction of FL.

Results

An algorithm based on BMI, waist circumference, triglycerides and GGT had an accuracy of 0.84 (95%CI 0.81–0.87) in detecting FL. We used this algorithm to develop the "fatty liver index" (FLI), which varies between 0 and 100. A FLI < 30 (negative likelihood ratio = 0.2) rules out and a FLI ≥ 60 (positive likelihood ratio = 4.3) rules in fatty liver.

Conclusion

FLI is simple to obtain and may help physicians select subjects for liver ultrasonography and intensified lifestyle counseling, and researchers to select patients for epidemiologic studies. Validation of FLI in external populations is needed before it can be employed for these purposes.