In the first study to examine the relationship between cumulative traumatic stress exposure and inflammation, the scientists found that the more traumatic stress a patient was exposed to over the course of a lifetime, the greater the chances the patient would have elevated levels of inflammatory markers in his or her bloodstream.
“This may be significant for people with cardiovascular disease, because we know that heart disease patients with higher levels of inflammation tend to have worse outcomes,” said Doctor Aoife O’Donovan of SFVAMC and UCSF.
The authors looked at exposures to 18 different types of traumatic events, all of which involved either experiencing or witnessing a direct a threat to life or physical integrity, in 979 patients age 45 to 90 with stable heart disease. They then measured a number of clinical markers of inflammation that circulate in the bloodstream, and found a direct correlation between degree of lifetime stress exposure and levels of inflammation.
Five years later, they measured the surviving patients’ inflammation markers again, and found that the patients who had originally reported the highest levels of trauma at the beginning of the study still had the highest levels of inflammation.
“Even though we lost some study participants because they died, we still observed the same relationship in those who remained,” O’Donovan said. “This suggests that it was not just the people who were the most sick at the outset who were driving this effect.”
Senior investigator Doctor Beth Cohen emphasised that the effect remained even after the researchers adjusted for psychiatric diagnoses such as post-traumatic stress disorder (PTSD), anxiety and depression. “Not everyone who is exposed to trauma develops PTSD,” said Cohen. “This study emphasises that traumatic stress can have a long-term negative impact on your health even if you do not go on to develop PTSD. It also tells us that, as clinicians, we need to think about not just which diagnostic box someone might fit into, but what their lifetime trauma exposure has been.”
Although the study did not probe the potential causes for the link between lifetime stress and inflammation, O’Donovan offered one possible explanation. “We know that in the aftermath of traumatic stress, people become more sensitive to threats,” she said. “This is actually pro-survival, because if you are in a dangerous environment, that alertness can help you avoid future harm.”
MEDICA.de; Source: The Veterans Health Research Institute