Post-traumatic stress disorder, obsessive-compulsive disorder, and anxiety disorders are all positively associated with high levels of inflammation markers in the blood, according to new research published in the journal Depression & Anxiety.

“Broadly, my research program examines the ways that emotions and physiology influence and relate to one another — that is, when someone experiences negative emotions (e.g., sadness, anxiety, anger) frequently and/or intensely what does that do to their physical health?” said study author Megan E. Renna of Columbia University.

“There has been a well-established link between chronic illness and anxiety in the literature over the years. But, it still has been unclear as to what processes, both psychologically and physically, contribute to this association, so I wanted to examine if inflammation may be one of these processes among people with anxiety, traumatic stress, and obsessive-compulsive related disorders.”

“Inflammation is associated with a whole host of chronic illnesses (HIV, cancer, cardiovascular disease, Alzheimer’s disease, etc.), so it felt especially important to see if chronic and pervasive anxiety increases inflammation. It is my hope that we can build interventions to better address the physical impact of anxiety and increase the quality of life and improve the physical health of people with anxiety and related disorders, and so this meta-analysis was one step in that direction.”

In the study, Renna and her colleagues examined 41 previous studies on individuals diagnosed with PTSD, OCD, or an anxiety disorder. All of the studies included control groups and had at least one measure of inflammation in the blood.

The researchers found people diagnosed with these disorders tended to have significantly higher level of pro-inflammatory markers compared to healthy control subjects. But there was no significant differences between people with PTSD, OCD, or an anxiety disorder.

“Anxiety, regardless of the specific type (e.g., fear, worry, hypervigilance) can not only take a toll on someone psychologically, but physically as well. In terms of the physical implications, systemic inflammation is something that is relatively invisible — meaning that the things that we feel can impact our bodies in ways that we may not fully be aware of,” Renna told PsyPost.

“Although we don’t yet necessarily know if this leads to health issues in the long term, it may be important to get treatment for your anxiety to better not only your mental health but your physical health as well.”

The study — like all research — includes some limitations.

“Two big questions still remain: First, PTSD seems to be driving the difference in inflammation between people with anxiety and healthy controls. But, there also seems to be much less research on other disorders compared to PTSD. I think it is important for the field to continue trying to understand how other types of anxiety increases inflammation. Also, it will be important to understand what makes PTSD different from the other disorders in terms of its impact on inflammation.”

“Second, this meta-analysis did not look at the processes contributing to greater inflammatory dysregulation in people with these disorders — many of the included studies did not measure what connects anxiety to inflammation. It is important in terms of next steps to be more mechanistic in our understanding of how anxiety is associated with inflammation in order to better learn how to intervene on this relationship and promote better long term health for people suffering from these disorders.”

The study, “The association between anxiety, traumatic stress, and obsessive–compulsive disorders and chronic inflammation: A systematic review and meta‐analysis“, was authored by Megan E. Renna, Mia S. O’Toole, Phillip E. Spaeth, Mats Lekander, and Douglas S. Mennin.