Patients with APS not taking anticoagulants at higher risk for thrombotic events

Patients with antiphospholipid syndrome who did not receive or were withdrawn from anticoagulation therapies had up to a 40% higher risk of having a thrombotic event during a 10-year period, according to research presented at the American College of Rheumatology Annual Meeting.

Of the 50 patients with antiphospholipid syndrome (APS) studied, anticoagulation drugs were withdrawn in 30 and not introduced in 20 patients. Eighteen percent of the patients also had systemic lupus erythematosus.

The researchers retrospectively collected patient data from the time of the patients’ inclusion in the study until July 2014 through the use of medical records and phone calls. Median follow-up was 80.5 months.

Twenty-one patients’ first APS thrombotic event was arterial, whereas 28 patients had venous thrombotic events. Additionally, one patient had catastrophic APS. Nineteen patients experienced thrombotic relapses in seven arterial events, 10 venous events and 2 catastrophic APS events, according to the researchers. No deaths occurred during the study period.

The risk for a thrombotic event was 16.4% at 12 months and 31% at 48 months, with a plateau of 40% at around 120 months.

Male sex, persistence of at least one antiphospholipid antibody and triple positivity at the withdrawal of anticoagulation were shown in univariate analysis to be greater risk factors for relapse, according to the researchers. A decreased risk was shown in long-term, antiplatelet treatment and elimination of antiphospholipid antibodies.

In multivariate analysis, the absence of antiplatelet prescription and the persistence of anticardiolipin antibodies were associated with relapse.

Reference:

Yelnik C, et al. Paper #L7. Presented at: American College of Rheumatology Annual Meeting. Nov. 14-19, 2014; Boston.

Disclosure: The authors have no relevant financial disclosures.