Anti-β2 glycoprotein-I antibody increases the risk of pregnancy-induced hypertension: a case-control study

The aim of this study was to evaluate whether IgG, IgM anti-β2 glycoprotein-I antibody (anti-β 2GPI) was associated with the development of pregnancy-induced hypertension (PIH) or pre-eclampsia in the Japanese population. This study was performed as a case-control study in cohort. The peripheral blood was obtained at 8-14 weeks of gestation from a consecutive series of 1,155 women. The case group comprises 36 patients who later developed PIH during their pregnancies. Of the 36 PIH patients, 13 had severe PIH, 18 had pre-eclampsia and 11 had severe pre-eclampsia. Age and parity matched 111 women whose pregnancies ended in normal delivery without obstetrical complications were selected as controls. We found that titers of IgG anti-β2GPI ≥1.0 Unit/ml represent a risk factor for severe PIH (P=0.023, OR 5.7 95%CI 1.4-22.8). In addition, titers of IgM anti-β2GPI ≥1.2 Unit/ml was found to be a risk factor for PIH (P=0.001, OR 8.8 95%CI 1.6-47.5). In women positive for anti-β2GPI but negative for lupus anticoagulant, anticardiolipin, phosphatidylserine dependent antiprothrombin, or kininogen dependent antiphosphatidylethanolamine antibody, the presence of anti-β2GPI was not a significant risk factor for development of PIH or pre-eclampsia. In conclusion, the presence of anti-β2GPI represent a risk factor for developing PIH and severe PIH, and support the utility of anti-β2GPI determination as one of the laboratory criteria for antiphospholipid syndrome classification. Usefulness of antiβ 2GPI measurement