title: Improvement in central arterial pressure waveform during hemodialysis is related to a reduction in asymmetric dimethylarginine (ADMA) levels.
abstract: BACKGROUND
  Cardiovascular mortality is high in hemodialysis (HD) patients. Early arterial pressure wave reflections, reflecting arterial stiffness and the endogenous nitric oxide synthesis inhibitor asymmetric dimethylarginine (ADMA) levels predict mortality in HD patients. Therefore, we aimed to study changes in ADMA levels and central arterial pressure waveform during HD.
  
  
  METHODS
  Thirty-two chronic HD patients were studied before and after a HD session. In a subset of 22 patients without arrhythmias, pulse wave analysis was performed on radial artery (SphygmoCor). Augmentation index (AIx), defined as difference between the second and first systolic peak divided by central pulse pressure, was used as a measure of arterial stiffness. ADMA was measured in plasma with the ELISA technique. Homocysteine was measured in plasma using the EIA technique.
  
  
  RESULTS
  HD reduced both AIx (19%; p = 0.003) and ADMA levels (17%; p < 0.001). The magnitudes of changes in AIx and ADMA during HD were correlated (r = 0.44; p = 0.045). Mean arterial pressure change was not significant. HD reduced homocysteine levels, but homocysteine was not related to ADMA or AIx.
  
  
  CONCLUSIONS
  The reduction in ADMA level seen after HD was associated with improvement in the central arterial pressure waveform, suggesting involvement of nitric oxide in the regulation of arterial stiffness in HD patients.
authors.affiliation: Department of Medical Sciences, Uppsala University, Uppsala, Sweden. inga.soveri@medsci.uu.se
authors.forename: Inga
authors.initials: I
authors.lastname: Soveri
authors.forename: Lars
authors.initials: L
authors.lastname: Lind
authors.forename: Björn
authors.initials: B
authors.lastname: Wikstrom
authors.forename: Mihkel
authors.initials: M
authors.lastname: Zilmer
authors.forename: Kersti
authors.initials: K
authors.lastname: Zilmer
authors.forename: Bengt
authors.initials: B
authors.lastname: Fellström
mesh_terms: D000368:Aged; D001120:Arginine / Q000031:analogs & derivatives* / Q000097:blood; D001794:Blood Pressure; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology* / Q000534:rehabilitation*; D008297:Male; D006435:Renal Dialysis
chemical_list: C018524:N,N-dimethylarginine; D001120:Arginine