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 analyzed plasma levels of FVIII and VWF in a case control study.
Methods:The study population consisted of 25 consecutive patients (of which 9 were excluded) admitted for CSVT to the department of Neurology of the Amiens University hospital from January 1997 to December 2002 with a general screening for thrombophilia. Sixty four healthy subjects matched according to age and sex formed the group control.
Results: The mean FVIII (CSVT: 167.3 IU/dl ± 48.8; control group: 117.9 IU/dl ± 39.8; p= 0.001) and VWF levels (CSVT: 165.4 % ± 76.5; control group: 108.5 % ± 27.8; p= 0.01) were significantly higher in CSVT group. Considering the 95th percentile of the control group as cut-off value, CSVT patients had elevated FVIII (>190 IU/dl) in 25 % (4/16) (p= 0.005) and elevated VWF (> 168 %) in 37.5 % (6/16) (p< 0.001). Using previously reported cut-off values (>150 IU/dl or >150%) led to the same results (FVIII: p= 0.005; VWF: p= 0.009).
Conclusion:Our study suggests that elevation of plasma factor VIII level 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.
- cerebral venous thrombosis
- factor viii
- von Willebrand factor