The Influence of ABO Blood Type on Hemostatic Activation Following A Marathon: 1400 Board #53 June 2, 8: 00 AM - 9: 30 AM.

Acute aerobic exercise such as marathon running stimulates an increase in both coagulation and fibrinolysis. Normally, this exercise-induced hemostatic activation is not detrimental as the balance between coagulation and fibrinolysis is maintained. However, recent evidence has established that certain risk factors (i.e., sustained air travel, oral contraceptive use) may disproportionately activate the coagulation cascade without proportional compensation by fibrinolysis, therefore increasing the risk of deep vein thrombosis in otherwise healthy athletes. Individuals with nontype-O blood also have an increased risk of thrombotic events, but the influence of blood type on exercise-induced hemostatic activation has not been established. PURPOSE: This study investigated the influence of ABO blood type (O, n=19; Non-O, n=10) on hemostatic activation in 29 young (35.8±6.5 years), healthy (23.0±6.3 kg·m-2) female oral-contraceptive using runners flying to and competing in the 2015 Boston Marathon. METHODS: Venous blood samples were collected 24 hours before, immediately after, and 24 hours following the Boston Marathon. Samples were analyzed for thrombin-antithrombin complex (TAT), tissue plasminogen activator (t-PA), and ABO blood type. Repeated measures analysis of variance (RMANOVA) tested if the change in TAT and t-PA from baseline differed over time and by blood type. RESULTS: Baseline levels of TAT (p=0.82) and t-PA (p=0.33) did not differ among blood groups. TAT and t-PA (p<0.05) increased immediately following the marathon. By 24 hours post marathon, TAT levels returned to baseline (p=0.15) while t-PA levels remained slightly elevated from baseline (p=0.02). These changes were independent of blood type (p=0.43). CONCLUSIONS: Among female marathoners with potential risk factors for thrombosis, we found blood type did not further influence the hemostatic activation associated with acute prolonged endurance exercise. SUPPORT: This study was funded by the American College of Sports Medicine NASA Space Physiology Grant and the Connecticut Space Grant Consortium.