Background Thrombotic events are formal clinical criteria for the diagnosis of Antiphospholipid Syndrome (APS). By now there are no evidences if there is an antibody profile or a specific risk factor that can predict onset and/or recurrences of thrombosis in APS patients.
Objectives Retrospective analysis of antibody profile and cardiovascular risk factors in patients with Primary Antiphospholipids Syndrome (PAPS) and thrombotic events. Correlation of these factors with type of thrombotic event (arterial-A, venous-V) and numbers of events (singular-S or recurrent-R).
Methods The study included 96 PAPS patients (25 male, 71 female). Patients were divided into subgroups:-type of thrombotic event (A or V); -number of episodes (S or R). Mean age at first thrombotic event was 36.7 years (range: 12.6-68.9 yrs); mean age at first recurrent event was 40.8 yrs (range: 19.7-70.8 yrs); medium time of follow-up was 134 months(range: 8.2-427).
Results 61% of patients begin with a V event, while 38% with an A event.V events occurred in patients with a mean age significantly lower compared with patients with A events (median value:2 9.7yrs vs 38.4yrs, p<0.01). Regarding each cardiovascular risk factor considered, hypertension and cardiac disorders seemed to be the most frequent in patients with A vs V thrombosis (15.3% vs 54.1%, p<0.0001; 10.2% vs 67.6%, p<0.0001). In 31 patients(32.3%) we identified the trigger for the first thrombotic event, represented in most cases by the concomitant use of estroprogestinic treatment and by pregnancy or post-partum period. During the follow-up visits we reported 58 R in 38 patients(39%). Compared with the first event, 20 R occurred in the same area(5 A and 15 V)while others 18 R occurred in different areas than the previous. In 23 patients only one R was recorded, in 10 patients two R and in 5 patients three or more R. In younger patients the recurrence of thrombotic events was significantly associated to the triple positivity for antiphospholipid antibodies(aPL)(76.2% in patients<45 yrs-old vs 25.6% in patients>45 yrs-old, p=0.01). In all patients with R the most frequent trigger was the interruption of the therapy or an inadequate control of the anticoagulation therapy. In particular 61% of these patients did not take for various reasons any therapy and in 52.2% of cases that therapy was interrupted not more than 10 days.
Conclusions In our cohort, R of thrombosis occurred in about 40% of patients during a mean follow-up period of 10 yrs. The inadequate adherence to treatment, as expected, is significantly associated to R in over 50% of cases. In younger patients triple positivity for aPL is related to R. This finding underlines that it’s mandatory to consider the antibody profile during the risk stratification of our patients, together with all cardiovascular risk factors and other possible triggers like pregnancy/post-partum period or estroprogestinic treatment.
References Myakis S, et al. International consensus statement on an update of the classification criteria for definite Antiphospholipid Syndrome.J Thromb Haemost2006 feb;4:295-306. Ruiz-Irastorza G, et al. Evidence-based reccomandations for the prevention and long-term management of thrombosis in antiphospholipid antibody-positive patients:report of a task force at the 13th International Congress on Antiphospholipid antibodies. Lupus2011;20(2):206-218.
Disclosure of Interest None Declared