title: Tumor Necrosis Factor-α as a Predictor for the Development of Nonalcoholic Fatty Liver Disease: A 4-Year Follow-Up Study.
abstract: BACKGROUND
  Tumor necrosis factor (TNF)-α is associated with insulin resistance and systemic inflammatory responses. The aim of this study was to investigate the relationship between TNF-α and the development of nonalcoholic fatty liver disease (NAFLD) in a longitudinal study.
  
  
  METHODS
  Three hundred and sixty-three apparently healthy subjects (mean age, 40.5±6.1 years; male, 57.6%) without NAFLD were enrolled in 2003. Anthropometric and laboratory measurements were performed. The participants were grouped into tertiles according to their serum TNF-α levels from samples taken in 2003. At a 4-year follow-up, we compared the odds ratios (ORs) of the development of NAFLD according to the tertiles of TNF-α levels measured in 2003.
  
  
  RESULTS
  At the 4-year follow-up, the cumulative incidence of NAFLD was 29.2% (106/363). The group that developed NAFLD had higher levels of TNF-α than those in the group without NAFLD (3.65±1.79 pg/mL vs. 3.15±1.78 pg/mL; P=0.016). When the 2003 serum TNF-α levels were categorized into tertiles: incidence of NAFLD observed in 2007 was significantly higher with increasing tertiles (22.6%, 35.8%, and 41.5%, respectively; P<0.05). The risk of developing NAFLD was significantly greater in the highest tertile of TNF-α than in the lowest tertile after adjusting for age, smoking, and BMI (OR, 2.20; 95% confidence interval, 1.12 to 4.01; P<0.05).
  
  
  CONCLUSIONS
  Higher serum TNF-α levels in subjects without NAFLD were associated with the development of NAFLD. The results of study might suggest a pathologic role of inflammation in NAFLD.
authors.affiliation: Department of Gastroenterology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yun Yong
authors.initials: YY
authors.lastname: Seo
authors.affiliation: Department of Gastroenterology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yong Kyun
authors.initials: YK
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ji-Cheol
authors.initials: JC
authors.lastname: Bae
authors.affiliation: Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Mi Hae
authors.initials: MH
authors.lastname: Seo
authors.affiliation: Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Se Eun
authors.initials: SE
authors.lastname: Park
authors.affiliation: Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Eun-Jung
authors.initials: EJ
authors.lastname: Rhee
authors.affiliation: Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Cheol-Young
authors.initials: CY
authors.lastname: Park
authors.affiliation: Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ki-Won
authors.initials: KW
authors.lastname: Oh
authors.affiliation: Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sung-Woo
authors.initials: SW
authors.lastname: Park
authors.affiliation: Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Won-Young
authors.initials: WY
authors.lastname: Lee
keywords: Inflammation; Non-alcoholic fatty liver disease; Tumor necrosis factor-alpha