title: Coagulation factors as biological risk markers of endothelial dysfunction. Association with the thrombotic episodes of chronic hemodialysis patients.
abstract: OBJECTIVE
  The aim of our study was to assess the coagulation factors as endothelial dysfunction markers and prospectively their association with thrombotic episodes in chronic hemodialysis patients.
  
  
  METHODS
  Fifty-four randomly selected patients on chronic hemodialysis (HD), 34 men and 20 women were included in this study. Their mean age was 56 years and the mean hemodialysis duration was 53.0861.92 months. The variations of tissue factor pathway inhibitor (TFPI), thrombomodulin (TM) and von Willebrand factor (vWF) were studied. The above-mentioned parameters were measured before and after HD session. Low molecular weight heparin (tinzaparin) was administered to all patients during hemodialysis. The results were compared with those obtained from 20 healthy volunteer-controls, age and sex matched. After the initial assessment, all patients were followed for a period of 15 months.
  
  
  RESULTS
  Two patients experienced one hemorrhagic event each, regarding the upper and/or the lower gastrointestinal tract. Twenty patients showed at least one thrombotic episode. Eleven patients presented fistula thrombosis, four angina pectoris incidents and five thrombosis of the lower limbs. The rest of the patients did not experience any clinical symptomatology that could be attributed to coagulation disorders. Parameter differences between patients and controls were statistically significant (p<0.005 for TFPI and p<0.001 for TM and vWF) and were improved after hemodialysis session. The age and the elevated levels of the vWF were found to be significantly different (p<0.03 and p<0.02 respectively) between the groups of patients who experienced or not thrombotic episodes.
  
  
  CONCLUSIONS
  Coagulation factors TFPI, TM, and vWF are increased in hemodialysis patients and the clinical disorders are mainly thrombotic episodes. The age of patients and the elevated levels of vWF are associated with the thrombotic incidents. Hemodialysis contributes in the improvement of these coagulation factors, which could be considered as biological risk markers of endothelial dysfunction in chronic HD patients.
authors.affiliation: 1st Internal Medicine Department, Renal Unit, University Hospital AHEPA, Thessaloniki, Greece.
authors.forename: A
authors.initials: A
authors.lastname: Sioulis
authors.forename: P
authors.initials: P
authors.lastname: Malindretos
authors.forename: A
authors.initials: A
authors.lastname: Makedou
authors.forename: P
authors.initials: P
authors.lastname: Makris
authors.forename: D
authors.initials: D
authors.lastname: Grekas