They Don't Call 'em Bloodcurdling for Nothing Horror movie messes with coagulation parameter

Watching a horror movie caused a spike in blood coagulation factor VIII, providing unprecedented scientific support for the existence of fear-induced bloodcurdling, Dutch investigators reported. Blood draws before and after movie viewing showed a statistically significant 11.1 IU/dL increase in factor VIII after watching a scary movie (2010's "Insidious") versus an educational film but without evidence of thrombin induction, essential for clot formation (not so scary that it might cause a heart attack or stroke). The change in the coagulation parameter correlated with a visual analog scale (VAS) assessment showing that viewers found the horror movie more frightening than the educational one. http://www.medpagetoday.com/Cardiology/Prevention/55418?xid=nl_mpt_DHE_2015-12-28&eun=g721819d0r