Incidence of a first thromboembolic event in asymptomatic carriers of high-risk antiphospholipid antibody profile: a multicenter prospective study

Abstract

Persistent antiphospholipid (aPL) antibodies are occasionally found in subjects without prior history of thromboembolic events (TEs), raising the dilemma of whether to initiate or not a primary thromboprophylaxis. A first TE is considered rare in aPL carriers, but previous studies did not consider the aPL profile nor was the test positivity confirmed in a reference laboratory. In this study, 104 subjects with high-risk aPL profile (positive lupus anticoagulant, anticardiolipin, and anti-␤ 2 -glycoprotein I antibodies, triple positivity) confirmed in a reference laboratory, were followed up for a mean of 4.5 years. There were 25 first TEs (5.3% per year): the cumulative incidence after 10 years was 37.1% (95% confidence interval [CI], 19.9%-54.3%). On multivariate analysis, male sex (hazard ratio ‫؍‬ 4.4; 95% CI, 1.5-13.1, P ‫؍‬ .007) and risk factors for venous thromboembolism (hazard ratio ‫؍‬ 3.3; 95% CI, 1.3-8.5, P ‫؍‬ .01) were independent predictors for TEs. Aspirin did not significantly affect the incidence of TE. In conclusion, the occurrence of a first TE in carriers of high-risk aPL profile is considerable; it is more frequent among male subjects and in the presence of additional risk factors for venous TE. These data can help in the decision to initiate primary thromboprophylaxis in these subjects. (Blood. 2011; 118(17):4714-4718)

Risk factors detection in chronic thromboembolic pulmonary hypertension, a tool for risk quantification?

“…Abnormalities in coagulation and fi brinolysis pathways have been associated in the minority of CTEPH patients with most prevalent ones being LA and APA. Thrombophilia studies have shown that LA may be found in 10 % of CTEPH patients, and 20 % carry LA/APA or both (21,27,28). Contrary to other studies, LA/APA levels in our CTEPH patients were not increased.…”

Thrombotic recurrences and bleeding events in APS vascular patients: A review from the literature and a comparison with the APS Piedmont Cohort

“…Recently, the term "aPL profile" has replaced the term "category" of positivity, and good evidence has been published regarding the high predictive role of the "triple" positivity aPL profile, consisting in the simultaneous, persistent positivity for LA, aCL and anti-beta2glycoprotein I. APS patients with triple positivity, as well as asymptomatic patients with triple positivity are at higher risk of thrombosis and thrombotic recurrences [9] and [10].…”

The Laboratory Diagnosis of the Antiphospholipid Syndrome

“…Investigators have raised uncertainty in the definite Indian J Hematol Blood Transfus (Jan-Mar 2017) 33 (1):8-14 9 diagnosis of APS on the basis of a single positive test. This is based on the lower incidence of first thromboembolic events in carriers with isolated LAC positivity compared to carriers with triple positivity (5.9 vs. 37 % at 10 years) [14,15]. The risk of thrombosis was higher in carriers of two or three aPL antibodies when compared with those with single positivity [16].…”