Objectives To study the effect of the antiphospholipid syndrome (APS) on survival in Chinese patients with SLE
Methods A cohort of 679 southern Chinese patients who fulfill at least 4 of the ACR criteria for SLE from 1995 to 2011 was studied. The status of the patients at last clinical visits (alive or death) was evaluated. The cumulative survival rate over time was studied by Kaplan-Miere’s plot. For those who died during the course of their disease, data were censored at the time of their deaths whereas data of other patients were censored at the time of last clinic visits. APS was defined by the modified Sydney criteria in 2006, ie. presence of arterial or venous thrombosis, or miscarrages (recurrent abortion or intra-uterine death) plus any one of the following positive twice at least 12 weeks part: (1) lupus anticoagulant; (2) moderate to high titers of anticardiolipin antibodies (IgG or IgM); or (3) beta-2-glycoprotein-I. Comparison of the survival of patients with and without APS was made.
Results 679 SLE patients were prospectively followed (623 women, 92%). The mean age of onset of SLE was 32.5±13.6 years and the mean follow-up time of the entire cohort of patients was 117±89 months. 67 (9.9%) patients died during the course of illness and 33 (4.9%) patients were lost to follow-up. The main contributing causes of death were: infection (51%), cardiovascular events (12%), cerebrovascular events (16%), and cancer (9%). 44 (6.5%) patients qualified the criteria for secondary APS. The clinical manifestations of APS in these patients were, in decreasing order of frequency, cerebrovascular accident (N=24, 55%), deep venous thrombosis (N=13, 30%), recurrent abortion/intrauterine fetal death (N=5, 11%), cardiovascular events (N=4, 9%) and peripheral vascular disease (N=4, 9%). Eight of 44 (18%) patients with APS died, which was more frequent in non-APS patients (59 deaths/635 patients, 9%; p=0.056). The cumulative mortality of patients with APS was 4.7% at 5 years, 7.8% at 10 years and 22.2% at 15 years, whereas the cumulative mortality of patients without APS was 5.2% at 5 years, 8.8% at 10 years and 10.9% at 15 years. Although the survival of APS patients was poorer than those without APS, the difference did not reach statistical significance (log rank test; p=0.23). However, if patients with APS involving only arterial thrombosis were considered, the presence of APS was significantly associated with mortality (HR 2.11 [1.004-4.45]; p=0.049).
Conclusions The presence of APS increases the mortality risk of patients with SLE, which is mainly contributed by arterial thrombotic events that occur late in the disease course.
Disclosure of Interest None Declared