It is widely known that post-traumatic stress disorder (PTSD) may lead to a number of physical, mental, and emotional difficulties.

Now researchers are finding that PTSD may be linked to, or even cause, several chronic conditions.

ra and ptsd

A study out of Harvard Medical School and the National Institutes of Health (NIH) discovered a definitive increase in PTSD symptoms among female RA patients.

The results, published in the medical journal Arthritis Care and Research, showed a correlation between the two conditions. A significant number of the patients diagnosed with PTSD later developed RA.

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Establishing the Link

Dr. Yvonne C. Lee and colleagues from Harvard Medical School in Boston studied 54,224 female nurses from 1989 to 2011.

Participants completed a brief trauma questionnaire and were screened for PTSD.

The participants were later classified according to both trauma exposure and their number of PTSD symptoms. At that time, 239 women in the study also had RA.

The study found that the women who had four or more symptoms of PTSD were also at a higher risk for developing RA compared with those who had no or little exposure to any kind of trauma.

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What Does it Mean?

It is unclear why there is an association between RA and PTSD.

Over the years, several studies have tried to uncover why one of these conditions may cause the other or if they frequently coexist in certain patients.

However, multiple studies have shown that RA patients face a higher risk for mental, emotional, or neuropsychiatric conditions, often because of chronic pain and illness.

Additionally, patients with depression, anxiety, and other mental or emotional disorders also exhibit physical symptoms, including pain. So, it wouldn’t be a surprise if PTSD also coexisted with pain in certain patients.

It should also be noted that life might be stressful for certain patients living with a chronic illness. From a psychological standpoint, and depending on a patient’s age at diagnosis and the severity of their symptoms, patients with RA may have to mourn the loss of their healthier, more active selves. This may also be a contributing factor in developing some level of PTSD.

According to the authors of the most recent study on PTSD and RA, "Further studies are necessary to examine the role of other behaviors and clinical characteristics, such as alcohol consumption and obesity, as potential confounders and/or mediators of the association between PTSD and risk for RA.”

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Connection with Veterans

A 2015 study focusing on veterans also showed a link between PTSD and RA.

The presence of at least four PTSD symptoms was associated with a 76 percent increased risk of RA compared with people who had no history or symptoms of trauma.

Lee, who was also involved in this study along with a team of researchers, speculated that inflammation may play a role, but no one knows for sure.

"I noticed years ago in working with [military] veterans that people who have severe chronic PTSD also had inflammatory diseases," Joseph A. Boscarino, Ph.D., of the Geisinger Clinic in Pennsylvania, wrote in an online column.

"They tended to have diseases like rheumatoid arthritis and psoriasis and it was thought to relate to an increase in the immune response," Boscarino noted.

The physiology behind why PTSD is associated with a risk for developing diseases like RA in nurses and veterans may not yet be known. However, this discovery could be a potential piece of the complex puzzle surrounding autoimmunity.