title: Efficacy of aspirin for the primary prevention of thrombosis in patients with antiphospholipid antibodies: an international and collaborative meta-analysis.
abstract: We performed a meta-analysis to determine whether aspirin has a significant protective effect on risk of first thrombosis among patients with antiphospholipid antibodies (aPL+). Observational and interventional studies identified from the Medline, Embase and Cochrane databases were selected if they assessed the incidence of first thrombosis in aPL+ patients treated with aspirin versus those without. Pooled effect estimates were obtained using a random-effects model. Of 1211 citation retrieved, 11 primary studies (10 observational and 1 interventional) met inclusion criteria, including a total of 1208 patients and 139 thrombotic events. The pooled odds ratio (OR) for the risk of first thrombosis in patients treated with aspirin (n=601) was 0.50 (95%CI: 0.27 to 0.93) compared to those without aspirin (n=607), with significant heterogeneity across studies (I(2)=46%, p=0.05). Subgroup analysis showed a protective effect of aspirin against arterial (OR: 0.48 [95%CI: 0.28-0.82]) but not venous (OR: 0.58 [95% CI: 0.32-1.06]) thrombosis, as well as in retrospective (OR: 0.23 [0.13-0.42]) but not prospective studies (OR: 0.91 [0.52-1.59]). Subgroup analysis according to underlying disease revealed a significant protective effect of aspirin for asymptomatic aPL+ individuals (OR: 0.50 [0.25-0.99]), for systemic lupus erythematosus (SLE) (OR: 0.55 [0.31-0.98]) and obstetrical antiphospholipid syndrome (APS) (OR: 0.25 [0.10-0.62]). This meta-analysis shows that the risk of first thrombotic event is significantly decreased by low dose aspirin among asymptomatic aPL individuals, patients with SLE or obstetrical APS. Importantly, no significant risk reduction was observed when considering only prospective studies or those with the best methodological quality.
authors.affiliation: Department of Internal Medicine, French National Reference Center for Systemic Lupus and Antiphospholipid Syndrome, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, 47-83 bd de l'hôpital, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (INSERM), UMR-S 945, Paris, France; Université Pierre et Marie Curie, UPMC Univ Paris 06, Paris, France. Electronic address: Laurent.arnaud@psl.aphp.fr.
authors.forename: Laurent
authors.initials: L
authors.lastname: Arnaud
authors.affiliation: Department of Internal Medicine, French National Reference Center for Systemic Lupus and Antiphospholipid Syndrome, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, 47-83 bd de l'hôpital, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (INSERM), UMR-S 945, Paris, France; Université Pierre et Marie Curie, UPMC Univ Paris 06, Paris, France.
authors.forename: Alexis
authors.initials: A
authors.lastname: Mathian
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: Hospital for Special Surgery, Weill Cornell Medical College, New York, USA.
authors.forename: Doruk
authors.initials: D
authors.lastname: Erkan
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 Autoimmune Diseases, Hospital Clínic-Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Barcelona, Catalonia, Spain.
authors.forename: Ricard
authors.initials: R
authors.lastname: Cervera
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: 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 U961, Vandœuvre-Les-Nancy, France.
authors.forename: Stephane
authors.initials: S
authors.lastname: Zuily
authors.affiliation: Nancy University Hospital, Université de Lorraine, INSERM U961, Vandœuvre-Les-Nancy, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Wahl
authors.affiliation: Department of Internal Medicine, French National Reference Center for Systemic Lupus and Antiphospholipid Syndrome, AP-HP, Groupe Hospitalier Pitié-Salpêtrière, 47-83 bd de l'hôpital, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (INSERM), UMR-S 945, Paris, France; Université Pierre et Marie Curie, UPMC Univ Paris 06, Paris, France.
authors.forename: Zahir
authors.initials: Z
authors.lastname: Amoura
mesh_terms: D017152:Antibodies, Antiphospholipid / Q000627:therapeutic use*; D016736:Antiphospholipid Syndrome / Q000188:drug therapy / Q000453:epidemiology; D001241:Aspirin / Q000009:adverse effects / Q000627:therapeutic use*; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000188:drug therapy / Q000453:epidemiology; D012307:Risk Factors; D013927:Thrombosis / Q000453:epidemiology / Q000517:prevention & control*
chemical_list: D017152:Antibodies, Antiphospholipid; D001241:Aspirin
keywords: Antiphospholipid antibodies; Aspirin; Meta-analysis; Thrombosis