title: D-dimer, factor VIII and von Willebrand factor predict a non-dipping pattern of blood pressure in hypertensive patients.
abstract: OBJECTIVE
  The aim of this study is to assess whether the haemostatic markers D-dimer, factor VIII (FVIII) and von Willebrand factor (VWF) are predictive of non-dipping status in treated hypertensive patients; so, as easy available laboratory data can predict non-dipping pattern and help with the selection of the patients whom circadian blood pressure should be re-examined.
  
  
  METHODS
  Forty treated hypertensive patients with essential hypertension were included in the study. Twenty-four-hour ambulatory blood pressure monitoring was performed in all patients. Daytime and nocturnal average systolic, diastolic and mean blood pressures were calculated. Patients were characterised as "non-dippers" on the basis of a less than 10 % decline in nocturnal blood pressure (BP); either systolic or diastolic or mean (MAP). D-dimer as marker of fibrinolytic function, FVIII activity and VWF antigen as marker of endothelial dysfunction were measured on plasma. The predictive efficiency was analysed by receiver operating characteristic (ROC) curves. Youden index was used for the estimation of the cut-off points and the associated values for sensitivity and 1-specificity.
  
  
  RESULTS
  Plasma levels of D-dimer, FVIII and VWF were significantly higher in non-dippers as compared with dippers, irrespective of the classification used (BP index); all P < 0.05. The ROC curves indicated a good diagnostic efficiency for D-dimer (AUC(ROC) = 0.697, 0.715 and 0.774), FVIII (AUC(ROC) = 0.714, 0.692 and 0.755) and VWF (AUC(ROC) = 0.706, 0.740 and 0.708) in distinguishing non-dipping pattern (systolic, diastolic or mean) in the study population; all P < 0.05. Among the three haemostatic markers, D-dimer presents the most satisfactory sensitivity/1-specificity for the differentiation of non-dippers, with a cut-off point >168 ng/ml (sensitivity/1-specificity for systolic BP non-dippers of 0.789/0.381, for diastolic BP non-dippers 0.923/0.444 and for MAP non-dippers 0.875/0.375).
  
  
  CONCLUSIONS
  In conclusion, D-dimer has a good predictive value for non-dipping pattern and the decision for the 24-h ambulatory blood pressure re-monitoring among dippers could rely on its values.
authors.affiliation: Department of Hematology Laboratory, General Hospital of Xanthi, Ephessou 68, 67100, Xanthi, Greece. vhrissan@civil.duth.gr
authors.forename: Athanasia
authors.initials: A
authors.lastname: Agorasti
authors.forename: Theodoros
authors.initials: T
authors.lastname: Trivellas
authors.forename: Efthimia
authors.initials: E
authors.lastname: Mourvati
authors.forename: Vasilios
authors.initials: V
authors.lastname: Papadopoulos
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Tsatalas
authors.forename: Vasilios
authors.initials: V
authors.lastname: Vargemezis
authors.forename: Ploumis
authors.initials: P
authors.lastname: Passadakis
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D002940:Circadian Rhythm / Q000502:physiology*; D018450:Disease Progression; D005169:Factor VIII / Q000378:metabolism*; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism*; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012372:ROC Curve; D014841:von Willebrand Factor / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D; D014841:von Willebrand Factor; D005169:Factor VIII