The influence of ABO blood group on mortality in major trauma

ABO blood group has a profound influence on hemostasis as it is a major determinant of plasma levels of von Willebrand Factor. In vitro studies suggest that blood group O is a risk factor for increased severe bleeding while blood group non-O is a risk factor for thromboembolic events. Yet, the impact of ABO blood group outcome after multiple trauma is unknown. Retrospective multicenter case-control study from three level-1 trauma centers in Germany from 2012-2015. Inclusion criteria were severe trauma with an Injury severity score ≥9 and admission to an intensive care unit. 1281 patients (69.5% male) were included. Mean Injury Severity Score (ISS) was 21.1±12.4; mean age was 50.2±22.4 years. Distribution of blood groups was: O: 37.4%; A: 44%, B: 12.7 and AB: 5.8%. Hospital mortality depending on blood group was 9.7 (A), 10.4 (B), 6.8 (AB) and 12.7 (O) %. Multivariant logistic regression for mortality revealed an Odds ratio of 0.79 (A), 0.60 (B) and 0.54 (AB) without statistical significance (P=0.35 (A), 0.17 (B), 0.33 (AB)). Thromboembolic events (blood group O vs. others) occurred in 2.8 (O) vs. 3.3 (others) %, P=0.619. In this retrospective study on 1281 multiple injured patients, no relevant influence of ABO blood group on hemorrhage, thromboembolic events and mortality could be found.