Antiphospholipid syndrome (APS): Clinical and immunoserological differences between primary and secondary APS in a Colombian cohort

Abstract

Introduction: Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by recurrent thrombosis that can affect the arterial and venous circulation. Objective: To analyze the immunological and pharmacological differences, as well as the clinical outcomes of a cohort of patients with primary APS and secondary APS. Materials and methods: A retrospective cohort study was conducted that included 352 records of patients diagnosed with APS and treated between 2014 and 2018. A description is presented of the sociodemographic, clinical, and immunological profile of the population. A bivariate analysis performed using the chi-squared test to determine differences between groups with primary APS and secondary APS, and finally a multivariate analysis to search for associations with thrombotic clinical outcomes in patients with APS. Results: The mean age was 42.4 ± 14 years, and 84.6% were females. Two-thirds (67.6%) of the patients had a diagnosis of primary APS, and 32.4% of secondary APS, of which 84% were associated with systemic lupus erythematosus (SLE). Among the thrombotic events, the most frequent were deep vein thrombosis (17.3%) and stroke (9.9%). Obstetric events were frequent, with a prevalence of 39.4% for miscarriages. No differences were found in the sociodemographic or immunoserological profile when comparing the group of primary vs. secondary APS. Thrombotic events were more frequent in the primary APS group, although only pulmonary embolism reached statistical significance. There were no differences between the two groups as regards obstetric events, such as miscarriages. Women were found to be 5 times more likely to have a stroke and 3 times more to have deep vein thrombosis. The anti-β2GPI type IgM increased the probability of presenting miscarriages about 3 times in women with APS. Conclusion: The study contains one of the largest Colombian cohorts with APS reported so far, and although it is both clinically and sociodemographically similar to other cohorts, there is a higher prevalence of primary APS. There was a lower frequency of thrombotic complications compared to other cohorts. Patients with primary APS had a tendency to develop thrombosis, as has already been reported in the literature.