Background APS ACTION International Clinical Database and Repository (“Registry”) was created to study the natural course of persistently antiphospholipid antibodies (aPL)-positive patients with or without autoimmune disorders over 10 years. The main autoimmune disease associated with aPL is Systemic Lupus Erythematosus (SLE); limited data exist on the impact of SLE on the clinical phenotype of persistently aPL-positive patients.
Objectives Our objective was to compare the prevalence of clinical and laboratory characteristics of aPL-positive patients with or without SLE.
Methods A secure web-based data capture system is used to store patient demographics, pertinent aPL history, and aPL profile. The inclusion criteria include aPL positivity according to the Updated Sapporo Classification Criteria. Only patients fulfilling the ACR SLE Classification Criteria and those with no other autoimmune diseases were included in this cross sectional analysis to study the impact of SLE on aPL-positive patients. Baseline clinical characteristics were compared using χ2 or t-tests accordingly.
Results As of June 2015, 573 aPL-positive patients recruited from 24 centers; 130 (22.7%) were excluded due to other or overlapping autoimmune diseases, SLE-like disease (fulfilling 3/11 ACR SLE Classification Criteria), or missing data. The mean ages (± SD) of individuals with persistently positive aPL but without other autoimmune diseases (“aPL only”) (female: 218, 73%), and of those with SLE (“aPL with SLE”) (female: 110, 77%) were 44±13 and 49±77, respectively. The majority of patients were Caucasians in both groups (62% and 65%, respectively), followed by Latin Americans (19.3% and 10.5%). Table shows the distribution of the clinical and laboratory characteristics (historically and/or at registry entry). The frequency of criteria and non-criteria APS manifestations was not different between two groups except persistent thrombocytopenia and autoimmune hemolytic anemia, which were more common in the “aPL with SLE” group (14% vs 28% and 2% vs 12%, respectively; both p≤0.001). Nephrotic syndrome, chronic or end-stage renal disease, and hypocomplementemia were also more common in the “apL with SLE” group.
Conclusions Concomitant SLE diagnosis in persistently aPL-positive patients is associated with an increased risk of thrombocytopenia, hemolytic anemia, nephrotic syndrome, chronic or end-stage renal disease, and hypocomplementemia; however the risk of other non-criteria manifestations, thrombosis, and pregnancy morbidity remains the same.
Acknowledgement APS ACTION Members.
Disclosure of Interest None declared