Women with inherited bleeding disorders demonstrate heterogenicity in bleeding symptoms that do not always correlate to underlying clotting factor levels. This is problematic when predicting the bleeding risk, especially when haemostatic challenge is anticipated. The effect of thrombotic variables in reducing the overall bleeding tendency, have demonstrated a protective effect in cases of severe haemophilia.
To assess the correlation between bleeding tendency, haemostatic and thrombotic variables in women with inherited bleeding disorders.
Quantitative measurement of the bleeding tendency was assessed using the standardized ISTH Bleeding Assessment Tool. Pictorial Blood Assessment Chart (PBAC) was used to quantify the subjective assessment of menstrual blood loss. 78 women with inherited bleeding disorders (75 with von Willebrand disease and 3 carriers of haemophilia A) were included. Blood samples were then obtained from individuals for assessment of clotting factors (factor VIII and von Willebrand factor) and thrombophilia screen (lupus anticoagulant, antithrombin, protein C and protein S, factor V Leiden mutation and prothrombin mutation).
Bleeding score was inversely related to von Willebrand factor antigen (vWF:Ag), ristocetin cofactor (vWF:RCo) levels. A positive correlation was demonstrated with antithrombin III activity. Ten women tested positive for thrombotic markers. Multiple regression analysis did not reveal a significant correlation with presence of thrombotic marker on bleeding score.
Bleeding score is a useful assessment for bleeding phenotype and seems to correlate with vWF:Ag and vWF:RCo, which may by useful for assessment of the bleeding risk. Although there was no significant correlation demonstrated by the presence of a thrombotic marker, the levels of antithrombin III appears to affect the bleeding phenotype and this requires further consideration.
Halimeh:Octapharma AG: Investigator Other, Research Funding.