Prevention of thrombosis in antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is an acquired autoimmune condition characterized by thrombotic events, pregnancy morbidity, and laboratory evidence of antiphospholipid antibodies (aPL). Management of these patients includes the prevention of a first thrombotic episode in at-risk patients (primary prevention) and preventing recurrent thrombotic complications in patients with a history of thrombosis (secondary prevention). Assessment of thrombotic risk in these patients, balanced against estimated bleeding risks associated with antithrombotic therapy could assist clinicians in determining whether antithrombotic therapy is warranted. Thrombotic risk can be assessed by evaluating a patient's aPL profile and additional thrombotic risk factors. Although antithrombotic options for secondary prevention of venous thromboembolism (VTE) have been evaluated in clinical trials, studies in primary prevention of asymptomatic aPL-positive patients are needed. Primary prevention with aspirin may be considered in asymptomatic patients who have a high-risk aPL profile, particularly if additional risk factors are present. Secondary prevention with long-term anticoagulation is recommended based on estimated risks of VTE recurrence, although routine evaluation of thrombotic risk can assist in determining whether ongoing anticoagulation is warranted. Studies that stratify thrombotic risk in aPL-positive patients, and patients with APS evaluating antithrombotic and non-antithrombotic therapies will be useful in optimizing the management of these patients.