title: Association of angiopoietin-2 with renal outcome in chronic kidney disease.
abstract: BACKGROUND
  The pathophysiological mechanisms of renal function progression in chronic kidney disease (CKD) have still not been completely explored. In addition to well-known traditional risk factors, non-traditional risk factors, such as endothelial dysfunction, have gradually attracted physicians' attention. Angiopoietin-2 (Ang-2) impairs endothelial function through preventing angiopoietin-1 from binding to Tie2 receptor. Whether Ang-2 is associated with renal function progression in CKD is unknown.
  
  
  METHODS
  This study enrolled 621 patients with stages 3-5 CKD to assess the association of circulating Ang-2 with commencing dialysis, doubling creatinine and rapid decline in renal function (the slope of estimated glomerular filtration rate (eGFR) greater than 5 ml/min per 1.73 m2/y) over follow-up of more than 3 years.
  
  
  RESULTS
  Of all patients, 224 patients (36.1%) progressed to commencing dialysis and 165 (26.6%) reached doubling creatinine. 85 subjects (13.9%) had rapid decline in renal function. Ang-2 quartile was divided at 1494.1, 1948.8, and 2593.1 pg/ml. The adjusted HR of composite outcomes, either commencing dialysis or doubling creatinine was 1.53 (95% CI: 1.06-2.23) for subjects of quartile 4 compared with those of quartile 1. The adjusted OR for rapid decline in renal function was 2.96 (95% CI: 1.13-7.76) for subjects of quartile 4 compared with those of quartile 1. The linear mixed-effects model shows a more rapid decrease in eGFR over time in patients with quartile 3 or more of Ang-2 than those with the lowest quartile of Ang-2.
  
  
  CONCLUSIONS
  Ang-2 is an independent predictor of adverse renal outcome in CKD. Further study is needed to identify the pathogenic role of Ang-2 in CKD progression.
authors.affiliation: Graduate Institute of Clinical Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Tsai
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Yi-Wen
authors.initials: YW
authors.lastname: Chiu
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Jer-Chia
authors.initials: JC
authors.lastname: Tsai
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Hung-Tien
authors.initials: HT
authors.lastname: Kuo
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Su-Chu
authors.initials: SC
authors.lastname: Lee
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chi-Chih
authors.initials: CC
authors.lastname: Hung
authors.affiliation: Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Ming-Yen
authors.initials: MY
authors.lastname: Lin
authors.affiliation: Graduate Institute of Clinical Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Institute of Population Sciences, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: Shang-Jyh
authors.initials: SJ
authors.lastname: Hwang
authors.affiliation: Graduate Institute of Clinical Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Mei-Chuan
authors.initials: MC
authors.lastname: Kuo
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Hung-Chun
authors.initials: HC
authors.lastname: Chen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D042702:Angiopoietin-2 / Q000097:blood*; D003404:Creatinine / Q000097:blood; D018450:Disease Progression; D005260:Female; D006801:Humans; D007668:Kidney / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D012307:Risk Factors
chemical_list: D042702:Angiopoietin-2; D003404:Creatinine