Recurrent thrombotic events in pediatric antiphospholipid syndrome: A systematic review and meta-analysis

Abstract

BackgroundPediatric antiphospholipid syndrome (APS) is one of the most common acquired hypercoagulable states in children, yet it remains poorly characterized. ObjectivesTo perform a systematic review and meta-analysis of the pooled incidence of thrombotic recurrence in this population (primary outcome), exploring the effect of age, APS type (primary vs. secondary to autoimmune diseases), and type of index thrombotic event. Secondary outcomes included the incidence of bleeding events and mortality. Materials and methodsThe MEDLINE, EMBASE, and COCHRANE databases were searched for studies reporting outcomes of cohorts of children aged ≤18 years with thrombotic APS as defined by the revised Sydney classification criteria. ResultsA total of 1011 studies were identified; of those, 9 were included in the final analysis (352 patients). The pooled incidence proportion of thrombosis recurrence was 0.27 [0.18–0.37], with an overall follow-up duration of a median of 2.7 to 5.8 years or a mean of 2.6 to 6.1 years. The estimate did not change meaningfully according to APS type (0.30 [0.18–0.46] for primary APS vs. 0.29 [0.19–0.42] for autoimmune APS), nor when the index thrombotic event was venous vs. arterial (0.30 [0.20–0.41] vs. 0.27 [0.27–0.51], respectively). The incidence of bleeding events was not reported in these studies. The incidence proportion of mortality was estimated at 0.07 [0.04–0.11] over the follow-up period, with 8/10 of the reported deaths directly associated with recurrent thrombotic events. ConclusionsThe incidence of thrombotic recurrence in children with APS is high and requires attention to evaluate anticoagulation management in this population.