Predictors of Mortality in Antiphospholipid Antibody Positive Patients: Prospective Results from Antiphospholipid Syndrome Alliance for Clinical Trials and International Networking (APS ACTION) Clinical Database and Repository (“Registry”)

The objective was to determine the mortality rate as well as the causes and predictors of mortality in antiphospholipid antibody (aPL)-positive patients with/without APS classification. The inclusion criteria for the multicenter international APS ACTION registry are positive aPL according to the Revised Sapporo Classification Criteria tested within one year prior to enrollment. Patients are followed every 12 ± 3 months with clinical data and blood collection. For this prospective analysis, firstly we analyzed the causes of death for patients reported as "deceased". Secondly, we analyzed risk factors for mortality using adjusted Cox proportional hazards model, and calculated the survival probability by Kaplan-Meier model based on different age groups. Of 967 patients, 43 (5%) were deceased after a median follow-up of 5.3 years. Based on the univariate analysis, deceased patients, compared to non-deceased, were more likely to be older and have a history of arterial thrombosis, catastrophic APS (CAPS), concomitant systemic autoimmune diseases (SAIDx), and baseline cardiovascular disease (CVD) risk factors. Based on the cox proportional hazards model adjusted for age and for each of the strongest predictors of mortality, arterial thrombosis (HR 2.94, 95% CI 1.50-5.76), concomitant SAIDx (HR 2.97, 95% 1.56-5.63), and baseline any CVD risk factor (HR 2.43, 95% CI 1.05-5.71) were significantly associated with mortality. In our cohort of persistently aPL-positive patients, the mortality rate was 5% after a median follow-up of five years, highest for patients over 60 years-old at registry entry. History of arterial thrombosis, concomitant SAIDx, and baseline any CVD risk factor independently predicted future mortality.