Part two: Low Cortisol levels linked to PTSD

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This is groundbreaking. Low cortisol levels have never been linked to PTSD before. This explains why we behave as we do.



“A shape was emerging that connected childhood adversity with low cortisol and the possibility of future PTSD.

So my team of five people landed in Cleveland, along with a centrifuge and other equipment. We stayed in my parents’ home, walking door to door to interview people by day and returning to test blood and urine samples in the evening. When the results came in, they were clear: half the Holocaust survivors had PTSD, and those with PTSD had low cortisol. There was no question about it—even if the traumatic experience was long ago, PTSD went hand in hand with low cortisol.

But why? And which came first? An important clue came from a 1984 review by Allan Munck and other researchers at the Geisel School of Medicine at Dartmouth. They noted that among stress hormones, cortisol played a special, regulatory role. High levels of stress hormones, if sustained for a long time, harm the body in multiple ways—weakening the immune system and increasing susceptibility to problems such as hypertension. But in a context of acute trauma, cortisol may paradoxically also have a protective effect. It shuts down the release of stress hormones—including itself—reducing the potential damage to organs and the brain. Such a trauma-induced feedback loop could conceivably reset the cortisol “thermostat” to a lower level.

I picked up another piece of the puzzle and placed it. In the early 1990s we’d shown that Vietnam veterans were more likely to develop PTSD if they’d been abused as children. Slowly a shape was emerging that connected intense childhood adversity—a period of “freeze” because a child usually cannot fight or flee—with low cortisol and the possibility of future PTSD. We studied people who’d been raped or who’d been in auto accidents when they came into emergency rooms, finding that those with lower cortisol levels were more likely to develop PTSD after the attack or accident.

Could low cortisol levels have been present before the event that brought them into the emergency room? I wondered. If someone with low cortisol was subjected to a traumatic experience, we reasoned, the cortisol levels in their bodies might be too low to tamp down the stress reaction. Adrenaline levels might then shoot way up, searing the memory of the new trauma into the brain—from where it might later surface as flashbacks or nightmares. Perhaps low cortisol marked a vulnerability to developing PTSD.

The study of Holocaust offspring supported this conjecture. Children of Holocaust survivors with PTSD tended to have low cortisol even if they did not have their own PTSD. As we’d suspected, low cortisol seemed related to vulnerability to PTSD.”



9 responses to this post.

  1. Therapy will not heal this

    This is groundbreaking, in my opinion

  2. So interesting. Thanks for sharing Marty.

  3. Game changer I think

  4. Posted by rudid96 on June 16, 2022 at 10:43 pm

    The science behind what survivors experience gives value to survivors. It’s NOT all in your head! Thanks for these teaching posts!

  5. More coming

  6. “In the early 1990s we’d shown that Vietnam veterans were more likely to develop PTSD if they’d been abused as children.” It’s very interesting to read this. I have come across this Vietnam study many time and this is the first time I have seen any reference to childhood trauma. It makes a lot of sense!

  7. I have five parts to this and the next is detailing how trauma is transferred in the womb

    This is what we inherit. Then if we were abused as kids that’s a double whammy

    Low cortisol means high adrenaline

    My mother was very high strung very much a worrier

    That adds to the firing of my fight or flight mechanism

  8. I find this incredibly interesting. Thank you for sharing!

  9. More answers

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