Clinical and therapeutic value of the adjusted Global Antiphospholipid Syndrome Score in primary obstetric antiphospholipid syndrome.

Objectives: (1) To assess the clinical utility of the adjusted global antiphospholipid syndrome score (aGAPSS) to predict new obstetric events during follow-up in primary obstetric antiphospholipid syndrome (POAPS) patients under standard-of-care treatment (SC) based on the use of low-dose aspirin (LDA) + heparin and (2) to study the risk of a first thrombotic event and to evaluate whether stratification according to this score could help to identify POAPS patients who would benefit from long-term thromboprophylaxis.

Methods: This is a retrospective, multicentre study. 169 women with POAPS were evaluated for the presence of a new obstetric event and/or a first thrombotic event during follow-up [time period: 2008-2020, median: 7 years (6-12 years)]. The outcomes of 107 pregnancies from these POAPS patients with SC were studied to evaluate relapses. Simple and multivariable logistic regression analyses were performed.

Results: Regarding obstetric morbidity, only triple positivity for antiphospholipid antibodies (aPLs) [OR = 8.462 (95% CI: 2.732-26.210); < 0.0001] was found to be a strong risk factor independently associated with treatment failure. On the other hand, triple positivity for aPLs [OR=10.44 (95% CI: 2.161-50.469), = 0.004] and an aGAPSS ≥7 [OR = 1.621 (95% CI: 1.198-2.193), = 0.002] were independent risk factors associated with a first thrombotic event. LDA was marginally associated with a decrease in the risk of thrombosis only in patients with aGAPSS ≥ 7 ( = 0.048).

Conclusion: aGAPSS appears to be useful in predicting the occurrence of a first thrombotic event in POAPS patients, and these stratification of patients could be helpful in selecting patients who would benefit from thromboprophylaxis with LDA.