Self-perceived quality of life of primary antiphospholipid syndrome patients using vitamin K antagonist

Primary antiphospholipid syndrome (PAPS) is a chronic autoimmune disorder clinically characterized by thromboembolic events or obstetric complications. Prolonged anticoagulation therapy with vitamin K antagonists (VKA) is the treatment of choice for PAPS patients with thrombosis. However, the efficacy of VKA therapy depends on laboratory monitoring, dose adjustment, adequate lifestyle and adherence to treatment. Difficulties with VKA therapy can affect patients' self-perceived health related quality of life (HRQOL). This study aims to evaluate PAPS patients' HRQOL, therapy adherence and knowledge of treatment.

A general Medical Outcome Study Short Form-36 (SF-36) and the Duke Anticoagulation Satisfaction Scale (DASS) were used to access APS-patients self-perceived HRQOL. Treatment adherence was measured by the Treatment Measure Adhesion (TMA) - oral anticoagulant version instrument, and knowledge of VKA treatment was measured using the MedTake test.

66 PAPS patients using VKA were assessed. 63% of them were female; the mean age was 41.9 years old, approximately 60% had unprovoked venous thrombosis and one third of the patients had recurrent thrombotic events. The most impacted domain of DASS was "psychological impacts" and the factors associated to anticoagulation related poor HRQOL were: female sex, presence of arterial thrombosis and INR lability. Using the SF-36 instrument, PAPS-patients self-perceived HRQOL was poorer than that of the general Brazilian population and was associated with female sex and presence of cardiovascular risk factors.

Despite the high adherence to treatment and knowledge of VKA therapy, self-perceived HRQOL is poor in patients with PAPS and is mainly affected by VKA therapy. Searching for better treatment options is warranted.