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Medical Author:

Maria Pease, MD

Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Who Develops PTSD?

Research has shown that different types of trauma create different rates of PTSD and that it can change the biochemistry of the brain. The combination of severe trauma, along with previous exposure to trauma creates the highest risk for PTSD. The more severe a trauma, the more likely you are to develop PTSD. If you have already experienced a trauma and you have low cortisol, your brain may be sensitized to trauma and react in a less functional manner to protect you from PTSD. Low levels of cortisol during a trauma may cause you to remember the scary event even more than the average person. Low cortisol may become a marker for those who might develop PTSD after a trauma.

Personal trauma such as rape or sexual abuse leads to a greater risk for PTSD as well. This may be due to the sense of personal betrayal that accompanies these types of traumas. Women suffer from higher rates of PTSD, and rape is thought to be the most likely trauma that may cause a woman to develop PTSD. This may be due to the intense helplessness of a smaller, less strong woman who is assaulted by a male.

People who are prone to PTSD over-respond to cues that resemble danger cues. They also still activate the "danger response” even as the danger cues decline. We are even learning that PTSD vulnerability can be passed on to the next generation in utero. Studies show that in women who were exposed to 9/11 and developed PTSD while pregnant note that their infants have lower than expected cortisol levels. It is hypothesized that during fetal development, the fetal brain's ability to process cortisol is negatively affected by their mothers hormones.

Major depression as well as chronic daily stress can cause chronically elevated levels of cortisol. The cortisol is constantly produced in an effort to reduce the hyperarousal state of excess flight or flight hormones. People with PTSD cannot mount this high cortisol response. We do know that too much cortisol is also problematic in different ways.