Primary thromboprophylaxis for asymptomatic people with persistent aPL antibodies who are thromboembolism-free

Bala, 2020Erkan, 2007Lim, 2016

Note: The presence of persistent antiphospholipid (aPL) antibodies alone does not confirm a diagnosis of antiphospholipid syndrome.

For asymptomatic people with systemic lupus erythematosus (SLE), or other inflammatory connective tissue disease, who have persistent antiphospholipid (aPL) antibodies, see specific management for this group.

Asymptomatic people are sometimes incidentally found to have aPL antibodies on assay, but no clinical manifestations to suggest antiphospholipid syndrome. This situation may arise when aPL antibodies are measured without an appropriate clinical indication. Even when aPL antibodies are persistent (ie 2 positive assays at least 12 weeks apart), asymptomatic people do not have a diagnosis of antiphospholipid syndrome.

Discuss the relevance of persistent aPL antibodies with the person, including their concerns, goals and expectations. Discuss that these antibodies carry a potential risk of thromboembolic events at a young age, and pregnancy-related complications. All people with persistent aPL antibodies should receive contraceptive advice and prepregnancy assessment and counselling, because of their increased risk of thromboembolism and pregnancy-related complications.

Prophylactic low-dose aspirin is often recommended for people with persistent aPL antibodies; however, published data about this are inconsistent, and some guidelines recommend low-dose aspirinArnaud, 2014 while others do notErkan, 2007. The consensus opinion of the Rheumatology Expert Group is that aspirin, even at prophylactic doses, has the potential for harm and should be considered on an individual basis for asymptomatic people with incidental, persistent aPL antibodies.

This advice is irrespective of the person’s cardiovascular risk factors or any associated inflammatory connective tissue disease.

The balance of risks versus benefits of low-dose aspirin is different for asymptomatic people with persistent high-risk aPL-antibody profiles who are trying to conceive; see specific management for this group.

Note: Aspirin, even at prophylactic doses, has the potential for harm and should be considered on an individual basis for asymptomatic people with incidental, persistent antiphospholipid antibodies.

All people with persistent aPL antibodies should be supported to address any modifiable cardiovascular risk factors they have, such as hypertension, diabetes, obesity, tobacco smoking and hyperlipidaemia.

In situations associated with a high risk of developing venous thromboembolism (VTE) (eg surgery, the peripartum period, prolonged immobilisation), asymptomatic people with persistent aPL antibodies should receive appropriate thromboprophylaxis (eg with low molecular weight [LMW] heparin). The appropriate regimen depends on the person’s risk factor(s). For details on thromboprophylaxis regimens in various situations, see VTE prophylaxis.