Fear of terror increases pulse, the risk of disease and subsequent death.
The jitters, cold sweats, fast heart rates, heavy breathing. Fear is known to provoke strong bodily reactions. But how much does fear really influence our health? Can fear make you ill? And if so, is this preventable?
In a study published in PNAS last December Shenhar-Tsarfaty and colleagues of the Hebrew University of Jerusalem demonstrated that a persistent state of fear may increase resting heart rate, which in turn increases the risk of serious illnesses, consequently increasing death rates.
Fear of terror
The scientists focused on the so-called ‘fear of terror’, which is experienced constantly by many people living in war zones and under the threat of terrorist attacks. Their goal was to understand if living under this type of stress, knowing that violence can strike unpredictably at any moment, could have effects on health. They conducted their research in Israel, a country that has been exposed to this kind of fear for over sixty years, and studied the reaction to ‘fear of terror’ of over 17.000 apparently healthy individuals. As an indicator of disease risk, the researchers measured the resting heart rate, which is the number of heart beats per minute, or put simply, the pulse. It is known that elevated pulse accompanies various medical conditions, including systemic inflammation and cardiovascular disorders. In turn, these medical conditions may promote states of illness leading to death.
To assess the level of fear of terror in people participating in the study, the scientists asked them a series of psychological questions concerning how worried they were about their personal safety, about being in crowded places, and about the possibility of a terrorist attack affecting their families. In addition, they measured a series of physical parameters that can influence heart rate, like smoking habits, sport activity, and the presence of indicators of inflammation. When they combined the scores and values obtained over several years from these analyses, they found that fear of terror significantly increased the annual pulse. This effect was particularly strong in individuals with high levels of inflammatory markers. In other words, people in a state of general, low-grade inflammation (that was not symptomatic and could derive from disparate causes) were more vulnerable to fear of terror and more exposed to the risk of falling ill and dying, especially from heart attacks and strokes.
This study suggests that pulse monitoring can be an effective preventive measure in populations under constant fear of terror: its variations can help identify persons who are apparently healthy but who in fact are at risk for developing a serious illness. Significant increases in pulse could be appropriately counteracted with medications combined with life-style changes (in diet, physical activity, sleeping habits), aimed at decreasing inflammation.
On the other hand, future research should address the biochemical mechanisms of “fear of terror” and try to understand how “fear of terror” contributes to increases in pulse and disease risk. It is known that the brain responds to fear by sending a series of chemical mediators into the body. These mediators influence the functions of various tissues and organs. This is essential to regulate body reactions to challenges: in the case of fear, the brain prepares the body to protect itself or to run away from the potential danger that provoked fear by increasing breath and heart rate, energy production and immune defenses. In a situation of chronic stress, like the stress caused by persistent “fear of terror”, these brain-periphery circuits can break down and produce abnormal responses that, if not controlled, may seriously damage health in the long term. Understanding which networks are specifically impacted by “fear of terror” to the extent of increasing pulse and the risks of illness and of death will be a very important challenge because it could open the way to developing suitable treatments to control the effects of this type of chronic stress.
Shenhar-Tsarfaty, S., Yayon, N., Waiskopf, N., Shapira, I., Toker, S., Zaltser, D., Berliner, S., Ritov, Y., & Soreq, H. (2015). Fear and C-reactive protein cosynergize annual pulse increases in healthy adults Proceedings of the National Academy of Sciences, 112 (5) DOI: 10.1073/pnas.1418264112
fear, terror, death, disease, pulse, sick, inflammation, ill, stress