Early mortality after heart transplantation related to IgA anti-β2-glycoprotein I antibodies

Abstract

Background: The presence of pre-formed IgA anti-β₂-glycoprotein I antibodies (IgA-aB2GP1ab) has been related to early graft loss after kidney transplant. Because β₂-glycoprotein I is produced in both the kidney and heart, we aimed to assess whether the presence of these antibodies may also be associated with poor outcomes after heart transplantation (HT).

Methods: A 2-year follow-up retrospective analysis of 151 consecutive patients who underwent HT between 2004 and 2012 was performed to assess the role of this pre-formed antibody type in HT. The population was divided into 2 groups according to the presence of IgA: Group 1 was positive for IgA-aB2GP1ab (47 patients, 31.1%), and Group 2 was negative for IgA-Ab2GP1ab (104 patients, 68.9%).

Results: Early mortality rates within the first 3 months were higher in Group 1 (27.7%) than in Group 2 (9.6%). No differences in donor and recipient characteristics or in causes of death were observed between groups. Multivariate analysis identified the presence of IgA-aB2GP1ab, female gender and blood type A as independent risks factors for early mortality after HT. A greater incidence of thrombotic events during the first 3 months post-HT in Group 1 (23.4% vs 5.8%) and a greater presence of risk factors for thrombotic events, which may have exacerbated them, were observed. After this period, no increase in mortality or in thrombotic events was found when the 2 groups were compared.

Conclusion: Pre-transplant presence of IgA-aB2GP1ab is associated with both increased early mortality rates and higher thrombotic events after HT.

Keywords: IgA anti–β(2)-glycoprotein I antibodies; anti-phospholipid syndrome; early graft failure; early mortality; heart transplantation complications; primary graft failure; thrombotic events.