Overview

• The University of Maryland meta-analysis combined data from 48 genetic studies spanning 17,000 ischemic stroke patients under 60 and nearly 600,000 controls to quantify risk by ABO blood group.
• Findings show individuals with blood type A face a 16% higher risk of early-onset ischemic stroke, while those with type O have a 12% reduced risk compared to other groups.
• Researchers hypothesize that differences in clotting proteins such as von Willebrand factor and factor VIII underlie the blood type associations, but the mechanisms remain to be defined.
• Blood groups B and AB exhibited weaker links to early stroke overall, with a slight elevation in risk for AB individuals in some East Asian populations.
• Specialists stress that despite genetic predispositions, lifestyle interventions—covering diet, exercise, smoking cessation and blood pressure control—remain the most effective stroke prevention measures.