As Dutch writer, psychiatrist, and researcher Bessel van der Kolk explained in his 2014 book of the same name, ‘the body keeps the score’.

Referring to the way in which a trauma victim’s body carries the after-effects of the trauma long after it has escaped their everyday thoughts, this seminal line changed the way in which doctors and therapists approached conditions like PTSD for good.

New research is always ongoing regarding the ways in which trauma – including childhood trauma, trauma related to a specific or devastating event, and more – affects the way that we live our lives, with enlightening results.

And a new study from the University of Oklahoma has given new emphasis to van der Kolk’s title, finding that amongst survivors of the 1995 Oklahoma City bombing, the body really does carry the after-affects of trauma long into the future.

Thirty years ago, Oklahoma City was subject to an attack of domestic terrorism when the Alfred P. Murrah Federal Building was targeted by a truck bombing.

Occurring just after 9am on April 19, 1995, the perpetrators were anti-government extremists who ultimately killed 168 people and injured another 684. As well as the federal building, 324 other buildings were damaged, causing hundreds of millions of dollars of damage.

But far beyond the damage to buildings and assets, the most striking damage, according to this study, was on the mental and physical health and wellbeing of the survivors.

Forty years on, the research team examined survivors to determine the long-lasting affects of their involvement in this traumatic situation.

Rather than just exploring the survivors’ mental health, the researchers looked for bodily signs of trauma that extend well beyond mental wellbeing: they looked for evidence of cortisol (a hormone involved in stress) and interleukins (proteins within the immune system that play a part in inflammation), as well as measuring blood pressure and heart rate.

They then compared the results to a control group of individuals who were not in any way affected by the Oklahoma City bombing, and the results – which were recently published in the journal Prehospital and Disaster Medicine – were staggering.

While the inflammatory interleukins were higher in the trauma survivors, their cortisol levels were lower. And while survivors had comparably higher blood pressure, they seemed to have lower heart rates.

This might seem counterintuitive, since we would expect trauma survivors to have a higher cortisol level (thanks to higher levels of ongoing stress) and a higher heart rate too.

But as Phebe Tucker, M.D., lead author of the study and professor emeritus of psychiatry at the OU College of Medicine explained in a statement, the results are much more profound, showing the real impacts of trauma:

“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.”

Amongst survivors of trauma, the study suggests, the body remains in a constant state of stress, even if the mind has learned to become numb to it – with potentially long-term effects:

“We thought there would be a correlation between these biomarkers and the research participants’ psychological symptoms, but their PTSD and depression scores were not elevated and did not correlate with stress biomarkers. That tells us there is a stress response in the body that is not present in the emotions they express.

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.”

Though the research is ongoing, this just goes to show the truly devastating human impacts of traumatic events that really can last a lifetime – even if you don’t realize it.

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