Factor levels in carriers of haemophilia are associated with familial severity: a Danish single centre study

Bleeding risk in hemophilia A and B carriers: comparison of factor levels determined using chronometric and chromogenic assays

“…We found a weak inverse correlation between BS and FVIII:C chronometric levels, in agreement with previous data suggesting that additional factors contribute to bleeding in HAC [6,9]. Previous studies on the influence of genetic and nongenetic factors on FVIII:C levels reported conflicting results [7,21,26,28,29]. In our study, no relationship between BS, factor levels, and genotype or familial hemophilia severity, von Willebrand factor level and ABO blood group was identified (data not shown).…”

“…In our sample, BS was clearly correlated with FIX:C levels, whatever the quantification method. As discussed for HAC, results are conflicting concerning the influence of genetic factors on FIX:C levels [23,25,26]. In our sample, hemophilia severity in male relatives and genotype did not influence FIX:C levels in HBC.…”

Comparative study of the prevalence of clotting factor deficiency in carriers of haemophilia A and haemophilia B

“…5 However, one larger study on carriers of HA and HB (171 carriers of HA and 41 of HB) described that carriers with severe haemophilia do seem to have lower clotting factor levels than carriers of moderate and mild haemophilia. 6 Furthermore, while levels of FVIII in carriers of HA were found to be dependent on the underlying mutation, 4 that was not true for the HB carriers. 5 We found that most carriers of HA with FVIII deficiency carry severe disease, which is not true for the HB, where most carriers with factor deficiency carry moderate disease.…”