Cerebral venous thrombosis and plasma concentrations of factor VIII and von Willebrand factor: a case control study.
BACKGROUND
High plasma concentrations of factor VIII (FVIII) and von Willebrand factor (VWF) have been recently associated with a moderately increased risk of venous thrombosis, but their roles in cerebral sinus and venous thrombosis (CSVT) have not been addressed. To determine whether elevation of FVIII and VWF is more frequent in CSVT, we analysed plasma levels of FVIII and VWF in a case control study.


METHODS
The study population consisted of 25 consecutive patients (of whom nine were excluded) admitted for CSVT to the Department of Neurology, Amiens University Hospital, France, from January 1997 to December 2002, for a general screening for thrombophilia. Sixty-four healthy subjects matched for age and sex formed the group control.


RESULTS
Mean FVIII (CSVT: 167.3 (SD 48.8) IU/dl; control group: 117.9 (39.8) IU/dl; p = 0.001) and VWF levels (CSVT: 165.4 (76.5)%; control group: 108.5 (27.8)%; p = 0.01) were significantly higher in the CSVT group. Using the 95th percentile of the control group as the cut off value, elevated FVIII (>190 IU/dl) occurred in 25% (4/16) (p = 0.005) and elevated VWF (>168%) in 37.5% (6/16) of patients with CSVT (p<0.001). Using previously reported cut off values (>150 IU/dl or >150%) showed the same results (FVIII: p = 0.005; VWF: p = 0.009).


CONCLUSIONS
Our study suggests that elevation of plasma factor VIII levels is the most common prothrombotic risk factor for CSVT. Elevation of VWF is also associated with an increased risk of CSVT but its effect seems to be partly mediated through FVIII.
Bugnicourt
Jean-Marc
JM
Department of Neurology and Laboratoire de Neurosciences Fonctionnelles et Pathologies (UMR CNRS 8160), University Hospital of Amiens, France. bugnicourt.jean-marc@chu-amiens.fr
Roussel
Bertrand
B
Tramier
Blaise
B
Lamy
Chantal
C
Godefroy
Olivier
O
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002561:Cerebrovascular Disorders / Q000097:blood*; D003392:Cranial Sinuses / Q000473:pathology; D005169:Factor VIII / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D020246:Venous Thrombosis / Q000097:blood*; D014841:von Willebrand Factor / Q000032:analysis*
D014841:von Willebrand Factor; D005169:Factor VIII