title: Elevated plasma YKL-40 as a prognostic indicator in patients with idiopathic pulmonary arterial hypertension.
abstract: OBJECTIVE
  Pulmonary vascular remodelling and inflammation have been implicated in pulmonary arterial hypertension (PAH). YKL-40, a marker of tissue remodelling and inflammation, has recently been recognized as a risk predictor of cardiovascular and inflammatory diseases. The study aimed to investigate a potential role of YKL-40 in predicting prognosis in idiopathic PAH (IPAH).
  
  
  METHODS
  Plasma YKL-40 levels were measured in 82 IPAH patients without current or previous PAH-specific treatment during right heart catheterization and in 54 healthy volunteers. Concurrent data included clinical, haemodynamic and biochemical variables.
  
  
  RESULTS
  Plasma YKL-40 levels were increased in IPAH patients compared with control subjects (median, interquartile range: IPAH: 24.90, 17.68-39.78 ng/mL; controls: 16.58, 14.20-19.64 ng/mL; P < 0.001). YKL-40 levels correlated with cardiac index (r = -0.244, P = 0.027) and N-terminal pro-brain natriuretic peptide (NT-proBNP, r = 0.263, P = 0.017). After a median follow-up of 578 days, YKL-40 outperformed NT-proBNP, uric acid, and 6-min walk distance in receiver operating characteristic (ROC) analyses in predicting both clinical worsening (area under the curve (AUC) 0.681) and death (AUC 0.717). Compared with patients with YKL-40 below the ROC-derived cut-off point (24.5 ng/mL), the high YKL-40 group showed higher pulmonary vascular resistance and serum uric acid levels, and showed more clinical worsening events and deaths in Kaplan-Meier analyses. Plasma YKL-40 was independently associated with clinical worsening in univariate and multivariate Cox analyses (all P < 0.05).
  
  
  CONCLUSIONS
  Plasma YKL-40 might serve as a promising indicator of disease severity and prognosis in patients with IPAH.
authors.affiliation: State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Guo
authors.initials: G
authors.lastname: Chen
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
authors.forename: Qing
authors.initials: Q
authors.lastname: Gu
authors.forename: Xin-Hai
authors.initials: XH
authors.lastname: Ni
authors.forename: Zhi-Hui
authors.initials: ZH
authors.lastname: Zhao
authors.forename: Jue
authors.initials: J
authors.lastname: Ye
authors.forename: Xian-Min
authors.initials: XM
authors.lastname: Meng
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Liu
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: He
authors.forename: Chang-Ming
authors.initials: CM
authors.lastname: Xiong
mesh_terms: D054392:Adipokines / Q000097:blood*; D000328:Adult; D015415:Biomarkers / Q000097:blood; D006328:Cardiac Catheterization / Q000379:methods; D002681:China; D000071451:Chitinase-3-Like Protein 1; D019468:Disease Management; D018450:Disease Progression; D065627:Familial Primary Pulmonary Hypertension / Q000097:blood / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D005260:Female; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D053208:Kaplan-Meier Estimate; D037102:Lectins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011652:Pulmonary Circulation; D012372:ROC Curve; D015203:Reproducibility of Results
chemical_list: D054392:Adipokines; D015415:Biomarkers; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; D037102:Lectins; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: YKL-40.; chitinase-like protein; pulmonary hypertension; survival