PURPOSE: Nonalcoholic fatty liver disease (NAFLD) is considered the liver component of the metabolic syndrome and is strongly associated with cardiometabolic diseases. In adults, cardiorespiratory fitness (CRF) is inversely associated with alanine aminotransferase (ALT), a blood biomarker for NAFLD. However, information regarding these associations is scarce for youth. The objective of this study is to examine associations between CRF, waist circumference, and ALT in youth. METHODS: Data were obtained from youth (n = 2844, 12-19 yr) in the National Health and Nutrition Examination Survey 2001-2004. CRF was dichotomized into youth FITNESSGRAM categories of "low" and "adequate" CRF. Logistic and quantile regression were used for a comprehensive analysis of associations, and variables with previously reported associations with ALT were a priori included in the models. RESULTS: Results from logistic regression suggested that youth with low CRF had 1.5 times the odds of having an ALT >30 than youth with adequate CRF, although the association was not statistically significant (P = 0.09). However, quantile regression demonstrated that youth with low CRF had statistically significantly higher ALT (+1.04, +1.05, and +2.57 U·L) at the upper end of the ALT distribution (80th, 85th, and 90th percentiles, respectively) than youth with adequate CRF. For every 1-cm increase in waist circumference, the odds of having an ALT >30 increased by 1.06 (P < 0.001), and the strength of this association increased across the ALT distribution. CONCLUSIONS: Future studies should examine whether interventions to improve CRF can decrease hepatic fat and liver enzyme concentrations in youth with ALT ≥80th percentile or in youth diagnosed with NAFLD.
PURPOSE:Nonalcoholic fatty liver disease (NAFLD) is considered the liver component of the metabolic syndrome and is strongly associated with cardiometabolic diseases. In adults, cardiorespiratory fitness (CRF) is inversely associated with alanine aminotransferase (ALT), a blood biomarker for NAFLD. However, information regarding these associations is scarce for youth. The objective of this study is to examine associations between CRF, waist circumference, and ALT in youth. METHODS: Data were obtained from youth (n = 2844, 12-19 yr) in the National Health and Nutrition Examination Survey 2001-2004. CRF was dichotomized into youth FITNESSGRAM categories of "low" and "adequate" CRF. Logistic and quantile regression were used for a comprehensive analysis of associations, and variables with previously reported associations with ALT were a priori included in the models. RESULTS: Results from logistic regression suggested that youth with low CRF had 1.5 times the odds of having an ALT >30 than youth with adequate CRF, although the association was not statistically significant (P = 0.09). However, quantile regression demonstrated that youth with low CRF had statistically significantly higher ALT (+1.04, +1.05, and +2.57 U·L) at the upper end of the ALT distribution (80th, 85th, and 90th percentiles, respectively) than youth with adequate CRF. For every 1-cm increase in waist circumference, the odds of having an ALT >30 increased by 1.06 (P < 0.001), and the strength of this association increased across the ALT distribution. CONCLUSIONS: Future studies should examine whether interventions to improve CRF can decrease hepatic fat and liver enzyme concentrations in youth with ALT ≥80th percentile or in youth diagnosed with NAFLD.
Authors: Nico S Rizzo; Jonatan R Ruiz; Anita Hurtig-Wennlöf; Francisco B Ortega; Michael Sjöström Journal: J Pediatr Date: 2007-04 Impact factor: 4.406
Authors: Kristy D M Wittmeier; Brandy A Wicklow; Andrea C MacIntosh; Elizabeth A C Sellers; Lawrence N Ryner; Hacene Serrai; Philip F Gardiner; Heather J Dean; Jonathan M McGavock Journal: Obesity (Silver Spring) Date: 2012-01-05 Impact factor: 5.002
Authors: Nathan A Johnson; Toos Sachinwalla; David W Walton; Kate Smith; Ashley Armstrong; Martin W Thompson; Jacob George Journal: Hepatology Date: 2009-10 Impact factor: 17.425
Authors: Kathy A Love-Osborne; Kristen J Nadeau; Jeanelle Sheeder; Laura Z Fenton; Phil Zeitler Journal: J Adolesc Health Date: 2008-03-04 Impact factor: 5.012
Authors: J Westerbacka; A Cornér; M Tiikkainen; M Tamminen; S Vehkavaara; A-M Häkkinen; J Fredriksson; H Yki-Järvinen Journal: Diabetologia Date: 2004-07-28 Impact factor: 10.122
Authors: Marion J Franz; Jeffrey J VanWormer; A Lauren Crain; Jackie L Boucher; Trina Histon; William Caplan; Jill D Bowman; Nicolas P Pronk Journal: J Am Diet Assoc Date: 2007-10
Authors: Yang Bai; Senlin Chen; Kelly R Laurson; Youngwon Kim; Pedro F Saint-Maurice; Gregory J Welk Journal: PLoS One Date: 2016-01-28 Impact factor: 3.240