Analysis Of Clinical Features And Risk Factors Of Antiphospholipid Syndrome With Thrombocytopenia

Objective:The purpose of this study was to better characterize the characteristics and role of thrombocytopenia in APS and to improve the management of APS;secondly,by analyzing risk factors in patients with antiphospholipid syndrome with thrombocytopenia,we aimed to guide clinical management and improve patient prognosis.Methods:The clinical data of APS patients in The Affiliated Hospital of Qingdao University from January 2010 to December 2021 were analyzed retrospectively.According to the etiology,they were divided into primary APS(PAPS)and secondary APS(SAPS).According to the platelet count,they were divided into thrombocytopenia group and normal platelet group.The clinical data and laboratory data of PAPS-thrombocytopenia group and PAPS-normal platelet group,as well as SAPS-thrombocytopenia group and SAPS-normal platelet group were compared.Univariate and multivariate Logistic regression analysis were used to screen risk factors for thrombocytopenia.Results:1.APS patients included a total of 173 cases.Among them,there were 100 PAPS patients,including 25 patients in the PAPS-thrombocytopenia group.The median platelet count in the PAPS-thrombocytopenia group was 71.0(62.0,82.0)×109/L.There were 73 patients with SAPS,including 37 patients with SAPS combined with thrombocytopenia.The median platelet count in the SAPS-thrombocytopenia group was 72.0(51.0,93.0)×109/L.2.The incidence of venous thrombosis was significantly higher in the PAPS-thrombocytopenic group(48%and 24%,χ2=5.143,P=0.023)than in the platelet-normal group.In contrast,the incidence of overall thrombotic events(32.4%and 61.1%,χ2=6.031,P=0.014)and venous thrombosis(13.5%and 38.9%,χ2=6.102,P=0.013)was significantly lower in the SAPS-thrombocytopenic group than in the platelet-normal group.3.The incidence of bleeding events was higher in the thrombocytopenic group of patients with PAPS(36%and 2.7%,χ2=21.280,P<0.001)and in the thrombocytopenic group of patients with SAPS(21.6%and 2.8%,χ2=5.994,P=0.014)than in the thrombocytopenic group of each group.4.In both PAPS and SAPS,the mean platelet volume levels were higher in the thrombocytopenic group than in the platelet-normal group.5.Multifactorial logistic regression analysis,the results suggest that low complement may be a risk factor for the development of thrombocytopenia in both the PAPS group(OR=2.853,95%CI=1.011 to 7.939,P=0.044)and the SAPS group(OR=6.596,95%CI=2.103 to 24.139,P=0.002).Conclusion:1.APS with thrombocytopenia is usually slightly decreased.2.The incidence of bleeding risk was significantly higher in the APS-thrombocytopenia group than in the normal group.When APS is accompanied by thrombocytopenia,it is necessary to guard against the occurrence of bleeding events.3.Mean platelet volume levels were elevated in the APS with thrombocytopenia group,and it is hypothesized that mean platelet volume is expected to be an independent predictor of the development of thrombocytopenia in patients with APS.4.Low complement in APS(either primary or secondary)may be a major risk factor for the development of thrombocytopenia,and therefore routine complement measurement is recommended in the clinical follow-up of patients with APS.5.The relationship between APS with thrombocytopenia and thrombosis is still quite complex,and further prospective studies with expanded sample lines are needed in the future.