PFA-100 Responsive to Effect of Energy Drinks on Platelet Function

Two previous studies have demonstrated increased platelet aggregation 60 minutes after
drinking a commercially available sugar-free energy drink. These studies utilized
traditional platelet function studies, such as light transmission aggregometry (LTA), where
platelet function is examined while adding varying concentrations of a panel of agonist to
platelets. These studies are technically difficult, time intensive studies requiring
specialized laboratories. They are relatively non-physiologic and do not mimic platelet
response to vessel wall damage. Other tests better represent the reactions to vessel wall
damage, including the PFA-100, which measures platelet aggregation and adhesion under
conditions of high shear.

Overall, PFA-100 is less expensive, requires less technical skill, and is less time
consuming than LTA. It has been utilized in bleeding disorders and is demonstrating promise
as a marker of thrombophilia. PFA-100 has demonstrated sensitivity to drug and dietary
effects. It has also shown differences in closure time between sedentary and athletic
individuals PFA-100 has not been used to investigate the effect of energy drinks.

Inclusion Criteria:

- a history of consuming at least one energy drink beverage in the past 6 months
without adverse effects;

- engage in moderate to strenuous physical activity more than 3 days per week.

Exclusion Criteria:

- Known thromboembolic risk including protein C or S deficiency, anti-thrombin III
deficiency, Factor V Leiden;

- history of thromboembolic event;

- current or previous anti-coagulation therapy, anti-platelet therapy, calcium
antagonists; - current tricyclic antidepressant therapy, current selective serotonin
re-uptake inhibitor therapy; antibiotic therapy; or famotidine therapy;

- acute illness;

- pregnancy;

- hemophilia;

- significant history of cardiovascular disease and/or diabetes mellitus;

- history of adverse effect of energy drinks.

- Inability to comply with pre-test dietary and activity requirements.