title: YKL-40 is a Protective Biomarker for Fatty Liver in World Trade Center Particulate Matter-Exposed Firefighters.
abstract: BACKGROUND
  Serum biomarkers of metabolic syndrome predict abnormal lung function in World Trade Center particulate matter (WTC-PM)-exposed Fire Department of New York (FDNY) rescue workers. In animal models, exposure to ambient PM induces non-alcoholic fatty liver disease (NAFLD), a well-known comorbidity of metabolic syndrome. YKL-40 is an inflammatory biomarker for both liver and lung disease. We tested if YKL-40 is a biomarker for NAFLD in this dust-exposed cohort.
  
  
  METHODS
  Using a nested case-control design, we studied 131 FDNY personnel who had Computer Tomography performed within 5 years post 9/11. NAFLD was defined by a liver/spleen attenuation ratio of ≤1. Serum biomarkers, lipid panel and liver function were measured in serum that had been drawn within 6 months of September 11, 2001. YKL-40 and chitotriosidase were assayed by ELISA. We tested biomarker and NAFLD association using logistic regression adjusted for age, BMI, and post-911 lung function.
  
  
  RESULTS
  NAFLD was present in 29/131 (22%) of the cohort. In a multivariable model increasing YKL-40 was protective while increasing triglyceride and alkaline phosphatase were risk factors for NAFLD.
  
  
  CONCLUSIONS
  Increased YKL-40 is a protective biomarker in non-alcoholic fatty liver disease. Further studies may reveal a link between PM-induced lung and liver diseases.
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA.
authors.forename: Soo Jung
authors.initials: SJ
authors.lastname: Cho
authors.affiliation: Division of Anestesiology, School of Medicine, Pontifical Catholic University of Chile-Santiago, Chile ; Department of Anesthesiology, New York University School of Medicine, New York, USA.
authors.forename: Ghislaine C
authors.initials: GC
authors.lastname: Echevarria
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA.
authors.forename: Young Im
authors.initials: YI
authors.lastname: Lee
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA.
authors.forename: Sophia
authors.initials: S
authors.lastname: Kwon
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA.
authors.forename: Kwan Yong
authors.initials: KY
authors.lastname: Park
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Tsukiji
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA ; Department of Environmental Medicine, New York University, School of Medicine, NY, USA.
authors.forename: William N
authors.initials: WN
authors.lastname: Rom
authors.affiliation: Bureau of Health Services and Office of Medical Affairs, Fire Department of New York, Brooklyn, NY, USA ; Pulmonary Medicine Division, Department of Medicine, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Prezant
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA ; Department of Environmental Medicine, New York University, School of Medicine, NY, USA ; Bureau of Health Services and Office of Medical Affairs, Fire Department of New York, Brooklyn, NY, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Nolan
authors.affiliation: Division of Pulmonary, Critical Care and Sleep, New York University, School of Medicine, New York, USA ; Department of Environmental Medicine, New York University, School of Medicine, NY, USA ; Bureau of Health Services and Office of Medical Affairs, Fire Department of New York, Brooklyn, NY, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Weiden
keywords: Biomarker; Non-alcoholic fatty liver disease; YKL-40