title: Patient-level analysis of five international cohorts further confirms the efficacy of aspirin for the primary prevention of thrombosis in patients with antiphospholipid antibodies.
abstract: We performed an individual patient meta-analysis to determine whether aspirin has a significant protective effect on the risk of first thrombosis among patients with antiphospholipid antibodies (aPL). Five international cohort studies with available individual patient-level data, reporting on primary prophylaxis with continuous treatment with low-dose aspirin in patients with aPL were included. The main outcome was the occurrence of a first thrombotic in patients with aPL treated with low-dose aspirin compared to those not treated with low-dose aspirin. Pooled Hazard Ratios (HRs) and 95%CIs were calculated using frailty models. We pooled data from 497 subjects and 79 first thrombotic events (3469 patient-years of follow-up). After adjustment on cardiovascular risk factors, aPL profiles, and treatment with hydroxychloroquine, the HR for the risk of a first thrombosis of any type in aPL carriers treated with low-dose aspirin versus those not treated with aspirin was 0.43 (95%CI 0.25-0.75). Subgroup analysis showed a protective effect of aspirin against arterial (HR: 0.43 [95%CI: 0.20-0.93]) but not venous (HR: 0.49 [95%CI: 0.22-1.11]) thrombosis. Subgroup analysis according to underlying disease revealed a protective effect of aspirin against arterial thrombosis for systemic lupus erythematosus (SLE) (HR: 0.43 [95%CI: 0.20-0.94]) and asymptomatic aPL carriers (HR: 0.43 [95%CI 0.20-0.93]). We found no independent protective effect of hydroxychloroquine. This individual patient data meta-analysis shows that the risk of first thrombotic event as well of first arterial thrombotic event is significantly decreased among SLE patients and asymptomatic aPL individuals treated by low-dose aspirin.
authors.affiliation: AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Institut E3M, Department of Internal Medicine & French National Reference Center For Systemic Lupus and Antiphospholipid Syndrome, F-75013, Paris; Inserm UMR-S 1136, Institut Pierre Louis d'Epidémiologie et de Santé Publique (iPLESP), F-75013 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, F-75013 Paris, France. Electronic address: Laurent.arnaud@psl.aphp.fr.
authors.forename: Laurent
authors.initials: L
authors.lastname: Arnaud
authors.affiliation: AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Institut E3M, Department of Internal Medicine & French National Reference Center For Systemic Lupus and Antiphospholipid Syndrome, F-75013, Paris; Sorbonne Universités, UPMC Univ Paris 06, F-75013 Paris, France.
authors.forename: Alexis
authors.initials: A
authors.lastname: Mathian
authors.affiliation: Service de médecine interne et maladies systémiques, Dijon, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Devilliers
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Padua, Padua, Italy.
authors.forename: Amelia
authors.initials: A
authors.lastname: Ruffatti
authors.affiliation: First Department of Internal Medicine, School of Medicine, National University of Athens, Athens, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Tektonidou
authors.affiliation: Department of Physiology, Favaloro University, Buenos Aires, Argentina.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Forastiero
authors.affiliation: Clinical Cardiology, Department of Cardiac Thoracic and Vascular Sciences, University of Padova, Padova, Italy.
authors.forename: Vittorio
authors.initials: V
authors.lastname: Pengo
authors.affiliation: Internal Medicine Department, Universitary Hospital, Lille, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Lambert
authors.affiliation: Internal Medicine Department, Universitary Hospital, Lille, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Lefevre
authors.affiliation: Institut Clínic of Gynecology, Obstetrics and Neonatology, Hospital Clínic-Institut d´Investigacions Biomèdiques August Pi i Sunyer, Faculty of Medicine-University of Barcelona, Barcelona, Spain.
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Martinez-Zamora
authors.affiliation: Institut Clínic of Gynecology, Obstetrics and Neonatology, Hospital Clínic-Institut d´Investigacions Biomèdiques August Pi i Sunyer, Faculty of Medicine-University of Barcelona, Barcelona, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Balasch
authors.affiliation: Nancy University Hospital, Université de Lorraine & INSERM U1116, Vandœuvre-Les-Nancy, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Wahl
authors.affiliation: AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Institut E3M, Department of Internal Medicine & French National Reference Center For Systemic Lupus and Antiphospholipid Syndrome, F-75013, Paris; Sorbonne Universités, UPMC Univ Paris 06, F-75013 Paris, France.
authors.forename: Zahir
authors.initials: Z
authors.lastname: Amoura
mesh_terms: D017152:Antibodies, Antiphospholipid / Q000276:immunology*; D001241:Aspirin / Q000627:therapeutic use*; D015331:Cohort Studies; D006801:Humans; D011322:Primary Prevention; D012307:Risk Factors; D013927:Thrombosis / Q000276:immunology / Q000517:prevention & control*; D016896:Treatment Outcome
chemical_list: D017152:Antibodies, Antiphospholipid; D001241:Aspirin
keywords: Antiphospholipid antibodies; Aspirin; Meta-analysis; Primary prevention; Thrombosis