Thrombotic risk in antiphospholipidic syndrome: From hypothesis to current evidence (Review)

Thirty-five years after it was first described, antiphospholipid syndrome (APS) is unanimously recognized as a systemic autoimmune disease, a major acquired thrombophilia, which can affect any arterial or venous vascular territory, explaining the great diversity of clinical manifestations. The current classification criteria updated in the International Consensus Statement for Definite Antiphospholipid Syndrome from Sydney cannot explain alone the unpredictable evolution with thrombotic events of the patients diagnosed with APS. Although the link to genetics and epigenetics has not been clearly defined as in other autoimmune diseases, it is clear that a proper stratification of thrombotic risk in the era of personalized medicine must include classic biological markers (antiphospholipid antibodies, aPL), along with the already recognized phenotypes, non-conventional serological markers, and additional genetic risk factors for thrombosis. Moreover, with advancing age, a patient with APS develops other thrombotic risk factors which include: hypertension and dyslipidemia among others. According to the classification criteria, a patient is considered to have a low, moderate or high thrombotic risk. In clinical practice, patients with the same risk score may have completely different evolutions in terms of the recurrence of thrombosis. Concerning this approach, it appears that new non-conventional serological markers, phenotype-assessment and genetic determinants have an increasing importance and should be reconsidered in a proper thrombotic risk evaluation in patients with APS, compared to the initial concept of APS as first defined.