Psychological trauma can unfortunately linger for years. However, according to recent research, it may even remain in the bodies of medically healthy people. The study, believed to be the first of its kind, was published in Prehospital and Disaster Medicine by a team at Oklahoma State University (OSU).
Previous examinations of terrorism survivors have focused on stress and psychological effects, but a team at OSU recently set out to analyze a set of different biological factors. What’s more, they did so by enlisting 60 medically healthy survivors from the same event—in this case, the 1995 Oklahoma City bombing.
Even after 30 years, the Oklahoma City bombing remains the deadliest domestic terror attack in US history. Largely planned and carried out by antigovernment conspiracy theorist and white supremacist Timothy McVeigh, the bombing involved detonating over 4,440 pounds of homemade explosives inside a Ryder truck parked near the Alfred P. Murrah Federal Building. The resultant blast leveled over one-third of the building, killing 167 people and wounding another 684 victims. Although many others survived were physically unscathed, they still possibly face long-term tolls from the experience.
The study focused on three bodily systems. The first is cortisol, a hormone which helps control stress. They also looked at blood pressure and heart rate, and inflammatory substances known as interleukins that function a person’s immune system.
The team soon saw striking differences between the survivors’ results with those of a control group of local residents unaffected by the bombing. Contrary to expectations, many survivors’ cortisol levels were lower. They also exhibited higher blood pressure, but lower heart rates in response to trauma cues. This suggests that their physiological responses to trauma dulled over time. Meanwhile, their interleukin 1B levels–those linked to inflammation–were higher. Interleukin 2R levels–responsible for immuno-protection–were lower.
“The main takeaway from the study is that the mind may be resilient and be able to put things behind it, but the body doesn’t forget. It may remain on alert, waiting for the next thing to happen,” Phebe Tucker, study lead author and OSU professor emeritus of psychiatry, said in a statement.
Tucker added that although they thought their analysis would show a correlation between the biomarkers and their psychological symptoms, the survivors’ PTSD and depression scores weren’t elevated and didn’t align with their hypothesis.
“That tells us there is a stress response in the body that is not present in the emotions they express,” Tucker explained. “In addition, the elevated interleukin 1B is typically seen in people with illnesses and inflammation, but this group was pretty healthy. However, it raises concerns about potential long-term health problems.”
Based on the study’s results, Tucker’s team believes that survivors of severe trauma may see noticeable changes in their biological systems’ baseline levels. Rachel Zettl, a study co-author and assistant professor of psychiatry and behavioral sciences, argued that these intense tragedies don’t only affect the brain, but the body itself.
“It’s not just our minds that remember trauma; our biological processes do, too,” she said. “It changes your actual physical being.”