Declaration of conflict of interest: None of the authors have conflicts of interest.
Non-alcoholic fatty liver disease as an independent manifestation of the metabolic syndrome: Results of a US national survey in three ethnic groups
Article first published online: 25 MAR 2013
Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Journal of Gastroenterology and Hepatology
Volume 28, Issue 4, pages 664–670, April 2013
How to Cite
Smits, M. M., Ioannou, G. N., Boyko, E. J. and Utzschneider, K. M. (2013), Non-alcoholic fatty liver disease as an independent manifestation of the metabolic syndrome: Results of a US national survey in three ethnic groups. Journal of Gastroenterology and Hepatology, 28: 664–670. doi: 10.1111/jgh.12106
- Issue published online: 25 MAR 2013
- Article first published online: 25 MAR 2013
- Accepted manuscript online: 3 JAN 2013 06:54AM EST
- Manuscript Accepted: 5 DEC 2012
- factor analysis;
- insulin resistance;
Background and Aim
The metabolic syndrome (MetS) and each of its components are strongly associated with non-alcoholic fatty liver disease (NAFLD). This has led many investigators to suggest that NAFLD is an independent component of the MetS. We formally tested this hypothesis using confirmatory factor analysis, which allows comparison of different models, with or without including NAFLD as a component of the MetS.
We analyzed data from 3846 subjects of the Third National Health and Nutrition Examination Survey (1988–1994). NAFLD was defined by increased liver fat measured by ultrasonography.
MetS by Adult Treatment Panel III criteria was present in 20.5%, and 30.2% had NAFLD, defined as mild, moderate, or severe ultrasonographic steatosis. Using confirmatory factor analysis, a basic model representing the MetS using its currently accepted components (glucose, waist, triglyceride/high-density lipoprotein ratio, and mean arterial pressure) showed excellent goodness-of-fit statistics. Addition of NAFLD to the model as a fifth independent variable decreased model fit, suggesting that NAFLD is not an additional independent component of the MetS. Analysis by ethnicity showed that addition of NAFLD decreased model fit in Whites but resulted in minor improvements in non-Hispanic Blacks and Mexican Americans.
The MetS is strongly associated with NAFLD. However, we found no evidence that NAFLD is an independent component or manifestation of the MetS. Interestingly, ethnic differences might be important in this relationship and require further study.