THROMBOSIS RESEARCH 65; 605-615,1992 0049-3848/92 $5.00 + .OO Printed in the USA. Copyright (c) 1992 Pergamon Press Ltd. All rights reserved.
THE BLEEDING TIME IN NORMAL SUBJECTS IS MAINLY DETERMINED PLATELET VON WILLEBRAND FACTOR AND IS INDEPENDENT FROM BLOOD GROUP Francesco Rodeghiero, Albert0 Tosetto
Giancarlo
Castaman,
Department of Hematology and Hemophilia San Bortolo Hospital, Vicenza, Italy
(Received
3.10.1991;
accepted
Marco
Ruggeri,
and Thrombosis
in revised form 27.12.1991
BY
and
Center,
by Editor S. Coccheri)
ABSTRACT Bleeding time (BT) is the most important test "in vivol' relationship evaluating the primary hemostasis. No between plasma von Willebrand factor (vWF) and BT has been found in normal subjects, whereas no data are available on the relationship between platelet vWF and blood group or BT in normal subjects. To clarify the reciprocal relationship between blood group, vWF and BT, we studied 177 normal subjects. The influence of blood group on BT was analyzed in 116 subjects and the distribution of platelet and plasma vWF between different blood groups in 111 subjects. Furthermore, in a subgroup of 50 subjects, a multivariate regression model, including age, platelet count, plasma and platelet vWF:Ag and Ristocetin Cofactor (RiCof), hematocrit, sex and 0 or non-0 blood group was used to assess the joint influence of these variables on BT. BT was similar in 0 and non-0 (P=O.310) and, plasma vWF although was group significantly lower in 0 group (P
THE BLEEDING TIME IN NORMAL SUBJECTS IS MAINLY DETERMINED PLATELET VON WILLEBRAND FACTOR AND IS INDEPENDENT FROM BLOOD GROUP Francesco Rodeghiero, Albert0 Tosetto
Giancarlo
Castaman,
Department of Hematology and Hemophilia San Bortolo Hospital, Vicenza, Italy
(Received
3.10.1991;
accepted
Marco
Ruggeri,
and Thrombosis
in revised form 27.12.1991
BY
and
Center,
by Editor S. Coccheri)
ABSTRACT Bleeding time (BT) is the most important test "in vivol' relationship evaluating the primary hemostasis. No between plasma von Willebrand factor (vWF) and BT has been found in normal subjects, whereas no data are available on the relationship between platelet vWF and blood group or BT in normal subjects. To clarify the reciprocal relationship between blood group, vWF and BT, we studied 177 normal subjects. The influence of blood group on BT was analyzed in 116 subjects and the distribution of platelet and plasma vWF between different blood groups in 111 subjects. Furthermore, in a subgroup of 50 subjects, a multivariate regression model, including age, platelet count, plasma and platelet vWF:Ag and Ristocetin Cofactor (RiCof), hematocrit, sex and 0 or non-0 blood group was used to assess the joint influence of these variables on BT. BT was similar in 0 and non-0 (P=O.310) and, plasma vWF although was group significantly lower in 0 group (P
