title: Antiphospholipid antibody profiles and their clinical associations in Chinese patients with systemic lupus erythematosus.
abstract: OBJECTIVE
  Different prevalences of antiphospholipid antibodies (aPL) have been reported in different populations of patients with systemic lupus erythematosus (SLE). Chinese are generally believed to have lower risk of vascular thrombosis. We examined the prevalence of aPL including lupus anticoagulant (LAC), anticardiolipin (aCL) and anti-beta2-glycoprotein I (anti-beta2-GPI) antibodies, the level of thrombotic risk, and the association of aPL with thrombotic and pregnancy outcomes in a Chinese cohort with SLE at the university lupus clinic during the period 1986-2003.
  
  
  METHODS
  aPL were measured in 272 SLE patients, and medical records were reviewed for vascular thrombosis and pregnancy outcomes.
  
  
  RESULTS
  The prevalence of LAC, IgG aCL, and IgG anti-beta2-GPI antibodies was 22.4%, 29.0%, and 7.7%, respectively. There were 38 episodes of thrombosis after a mean duration of followup of 11.0 +/- 6.8 SD years, giving a thrombotic rate of 1.26/100 patient-years. All aPL were shown to be associated with vascular thrombosis. IgG anti-beta2-GPI antibodies were found to be associated with recurrent thrombosis [8.0/100 patient-years or 25.0% (7/28)]. Patients taking hydroxychloroquine were found to have fewer thrombotic complications than those who were not (OR 0.17, 95% CI 0.07-0.44; p < 0.0001). LAC was the strongest factor associated with recurrent miscarriages [relative risk 12.3, 95% CI 1.22-123.31; p = 0.03). The diagnosis of secondary antiphospholipid syndrome was satisfied in 8.9% of patients.
  
  
  CONCLUSIONS
  The lifetime and recurrent thrombotic rates in our patients with aPL were not particularly different from those in the literature. However, the lower prevalence of aPL in our cohort may suggest a role of other prothrombotic factors in predisposition to thrombosis.
authors.affiliation: Department of Medicine, and the Clinical Trials Centre, Queen Mary Hospital, Hong Kong. mymok@netvigator.com
authors.forename: Mo Yin
authors.initials: MY
authors.lastname: Mok
authors.forename: Eric Yuk Tat
authors.initials: EY
authors.lastname: Chan
authors.forename: Daniel Yee Tak
authors.initials: DY
authors.lastname: Fong
authors.forename: Kate Fung Shan
authors.initials: KF
authors.lastname: Leung
authors.forename: Woon Sing
authors.initials: WS
authors.lastname: Wong
authors.forename: Chak Sing
authors.initials: CS
authors.lastname: Lau
mesh_terms: D000026:Abortion, Habitual / Q000150:complications / Q000208:ethnology / Q000276:immunology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D017152:Antibodies, Antiphospholipid / Q000097:blood*; D044466:Asian People; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006785:Hospitals, University; D006801:Humans; D008137:Longitudinal Studies; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000208:ethnology / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000208:ethnology / Q000276:immunology*; D013927:Thrombosis / Q000150:complications / Q000208:ethnology / Q000276:immunology*
chemical_list: D017152:Antibodies, Antiphospholipid