ABO Blood Group and Risk of Thromboembolic and Arterial Disease: A Study of 1.5 Million Blood Donors
Background—ABO blood groups have been shown to be associated with increased risks of venous thromboembolic and arterial disease. However, the reported magnitude of this association is inconsistent and is based on evidence from small-scale studies.
Methods and Results—We used the SCANDAT2 database of blood donors linked with other nationwide health data registers to investigate the association between ABO blood groups and the incidence of first and recurrent venous thromboembolic and arterial events. Blood donors in Denmark and Sweden between 1987 and 2012 were followed for diagnosis of thromboembolism and arterial events. Poisson regression models were used to estimate incidence rate ratios (IRR) as measures of relative risk. A total of 9,170 venous- and 24,653 arterial events occurred in 1,112,072 individuals during 13.6 million person-years of follow-up. Compared to blood group O, non-O blood groups were associated with higher incidence of both venous and arterial thromboembolic events. The highest rate ratios were observed for pregnancy-related venous thromboembolism [IRR 2.22; 95% confidence interval (CI, 1.77-2.79)], deep vein thrombosis (IRR 1.92; 95% CI, 1.80-2.05), and pulmonary embolism (IRR 1.80; 95% CI, 1.71-1.88).
Conclusions—In this healthy population of blood donors, non-O blood groups explain more than 30% of venous thromboembolic events. Although ABO blood groups may potentially be used with available prediction systems for identifying at-risk individuals, its clinical utility requires further comparison with other risk markers.
- ABO blood groups
- cardiovascular disease
- cerebrovascular disease/stroke
- arterial thrombosis
- Received May 18, 2015.
- Revision received January 26, 2016.
- Accepted February 24, 2016.