title: The PTH (1-84)/non-PTH (1-84) ratio is a risk factor for cardiovascular events in hemodialysis patients.
abstract: BACKGROUND
  We hypothesized that the PTH (1-84)/non-PTH (1-84) ratio (PTH ratio) might help to assess cardiovascular risk in hemodialysis patients.
  
  
  METHODS
  In this prospective cohort study 70 prevalent hemodialysis patients were followed up to 4 years. The PTH ratio was determined at baseline. Primary outcomes were cardiovascular events (CVE) and all-cause mortality. Cumulative event-free survival was compared between patients with a ratio < 1 and those with a ratio > 1. The risk-association of the PTH ratio with CVE was examined using an adjusted Multiple Cox Proportional Hazards model.
  
  
  RESULTS
  A PTH ratio > 1 was found in 34 patients (49%). During follow-up 26 patients suffered a CVE. Patients with a CVE showed a higher ratio than patients with event-free survival (p = 0.033). In patients with a ratio > 1 a significantly higher number of CVE occurred (53 vs. 22%; p = 0.013), and these patients showed a significantly shorter event-free survival (p = 0.032). In an adjusted Cox-proportional hazards model a higher PTH ratio was found to be independently associated with an elevated risk for CVE (HR = 3.2; 95% CI 1.06 - 13.63; p = 0.04).
  
  
  CONCLUSIONS
  A higher PTH (1-84)/non-PTH (1-84) ratio is associated with an increased risk for CVE in hemodialysis patients and might therefore be useful for cardiovascular risk estimation in this population.
authors.affiliation: Department of Internal Medicine IV, Nephrology and Hypertension, Innsbruck Medical University, Innsbruck, Austria.
authors.forename: E
authors.initials: E
authors.lastname: Zitt
authors.forename: A H
authors.initials: AH
authors.lastname: Kirsch
authors.forename: M
authors.initials: M
authors.lastname: Haueis
authors.forename: A
authors.initials: A
authors.lastname: Strasak
authors.forename: U
authors.initials: U
authors.lastname: Neyer
authors.forename: G
authors.initials: G
authors.lastname: Mayer
authors.forename: A R
authors.initials: AR
authors.lastname: Rosenkranz
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood* / Q000401:mortality*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000401:mortality / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D006435:Renal Dialysis; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D010281:Parathyroid Hormone