Anti-beta(2)-glycoprotein I antibodies in patients with acute venous thromboembolism: Prevalence and association with recurrent thromboembolism

To establish the prevalence of antibodies against beta(2)-glycoprotein I (b eta(2)GPI) in unselected patients with venous thromboembolism, as well as t he association with antiphospholipid antibodies (aPL) and a history of prev ious thromboembolism, we investigated the presence of these antibodies in 2 27 consecutive patients with acute deep vein thrombosis or pulmonary emboli sm, of whom 63 were carriers of aPL with or without lupus anticoagulant (LA ), and seven were carriers of LA alone. The presence of antibodies against beta(2)GPI was demonstrated in 19 patients [8.4%; 95% confidence interval ( CI), 4.5-11.3%]. All of them belonged to the group of 63 patients with aPL (30.2%). A history of a previous thromboembolism was identified in 11 of th e 19 patients with anti-beta(2)GPI antibodies (57.9%) and in 45 of the 208 patients without these antibodies [21.6%; odds ratio (OR) = 4.98; 95% CI, 1 .89-13.1; p<0.0005]. In the subgroup of patients with aPL and/or LA, the ra te of recurrent thromboembolism among patients with anti-beta(2)GPI antibod ies (11 of 19, 57.9%) was significantly higher than that observed in patien ts without these antibodies (15 of 51, 29.4%; OR = 3.3; 95% CI, 1.1-9.83; p = 0.28). We conclude that in patients with acute venous thromboembolism th e prevalence of antibodies against beta(2)GPI is unexpectedly high. The pre sence of these antibodies seems to identify a subgroup of patients with ant iphospholipid antibodies who have a peculiarly high risk of thrombotic recu rrences. Further prospective studies are indicated to better define the rol e of anti-P,GPI antibodies in the development of recurrent thromboembolism. (C) 1999 Elsevier Science Ltd. All rights reserved.