Because cardiac events are a major cause of in-line deaths in firefighters and caffeine use is common in this population, we sought to examine the effects of caffeine on the hemostatic response to firefighting drills.
Materials and Methods:
Twelve firefighters completed two trials of firefighting drills after consuming caffeine (6 mg/kg) or placebo. Factor VIII, tissue plasminogen activator (tPA), and plasminogen activator inhibitor-1 (PAI-1) were analyzed from pre- and post-exercise blood samples.
Results:
Factor VIII increase was larger (p < 0.05) in the caffeine trial (Pre = 0.20 ± 0.13 IU/mL, Post = 0.43 ± 0.15 IU/mL) than the placebo trial (Pre = 0.21 ± 0.11 IU/mL, Post = 0.38 ± 0.15 IU/mL). tPA activity significantly (p < 0.05) increased and PAI-1 activity significantly decreased (p < 0.05) by the same magnitude in both conditions.
Conclusions:
Results suggest that caffeine elicits a higher coagulation response during firefighting drills.
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