[The relationship between elevated antiphospholipid antibodies and thrombosis in hospitalized patients].

Assess the relationship between elevated antiphospholipid antibodies and thrombosis in hospitalized patients. Case control study. A total of 385 patients (149 males and 236 females, aged from 1 to 105 years, with a median age of 37 years) who were hospitalized in Peking University First Hospital from January 2015 to December 2019 and tested positive for any one of the anti-phospholipid antibodies were included in the study. All subjects were divided into thrombotic group and non-thrombotic group according to whether thrombus was detected by imaging examination during hospitalization. In thrombosis group, there were 66 males and 36 females, aged from 3 to 105 years, with a median age of 58 years. In non-thrombosis group, there were 83 males and 200 females, aged from 1 to 94 years, with a median age of 31 years. Clinical data and laboratory data of patients were recorded. ACL-IgM/IgG and anti-β2GPI-IgM/IgG were detected by ELISA and LA was detected by dRVVT and SCT on automatic coagulation analyzer. The rates of age, gender, smoking, obesity, hypertension, hyperlipidemia, diabetes and the median level of antiphospholipid antibodies were compared between two groups. Logistic multivariate regression analysis was used to determine the risk factors for thrombotic events. The mid-to-high titer value of aCL was established by the χ-trend test and verified by logistic regression. The median age (58 years) and the rates of male (64.7%), smoking (16.7%), hypertension (63.7%) and diabetes (28.4%) in thrombus group were significantly higher than those in non-thrombus group (=7.685, χ²=38.077, 16.312, 37.769, 24.749 respectively; <0.01). The positive rate of anti-β2GPI-IgG and dRVVT in thrombosis group (11.8% and 78.4%) was significantly higher than that in non-thrombosis group (5.3% and 60.1%), as well as the median level of dRVVT (1.29 RU/ml 1.23 RU/ml) (χ²=3.864 and 10.309, =3.539; <0.05). The median level of aCL-IgM was higher in non-thrombosis group (2.3 MPL 2.0 MPL). The positive rate of aCL-IgG was slightly higher in thrombosis group (18.6% 10.6%). Logistic regression analysis showed that men, hypertension, diabetes, advanced age, elevated dRVVT, and elevated anti-β2GPI-IgG are risk factors for thrombosis. Taking 36 GPL as the medium-to-high titer value of aCL-IgG, the risk of thrombosis increased by 2.45 times. In the anti-phospholipid antibody profile, LA detected by dRVVT method, anti-β2GPI-IgG and aCL-IgG may be valuable laboratory indicators for inpatient thrombotic events. The mid-to-high titer value of aCL-IgG is set at 36 GPL to distinguish the risk of thrombosis.