Researchers have linked psychosocial trauma with a higher risk of lupus.
What is more, researchers found that exposure to any traumatic event - even in the absence of post-traumatic stress disorder (PTSD) - may increase lupus risk.
Study leader Dr. Andrea Roberts, of the Harvard T.H. Chan School of Public Health in Boston, MA, and colleagues recently reported their results in the journal Arthritis & Rheumatology.
PTSD is a mental health condition that may arise after witnessing or being involved in a traumatic incident, such as a motor vehicle accident or military combat.
According to the United States Department of Veteran Affairs, around 8 million adults in the U.S. have PTSD in any given year, and around 7 to 8 percent of the country's population will develop the condition in their lifetime.
It is well established that PTSD can increase the risk of anxiety and depression, but less is known about how PTSD might impact physical health.
Some studies have suggested that people with PTSD may be at greater risk of heart failure, while other research has uncovered a link between PTSD and a greater risk of autoimmune disorders.
The new study from Dr. Roberts and colleagues provides further evidence of the latter, after linking psychosocial trauma and PTSD with a higher likelihood of systemic lupus erythematosus (SLE), which is the most common form of lupus.
Lupus is an autoimmune disease wherein the immune system mistakingly attacks healthy cells and tissues, causing inflammation. In SLE, various parts of the body can be affected, including the skin, joints, kidneys, heart, and brain.
According to Lupus Research Alliance, there are around 1.5 million people in the U.S. living with lupus, with more than 90 percent of cases arising in women aged between 15 and 44 years.
The new study included the data of 54,763 U.S. women, all of whom were assessed for PTSD and exposure to trauma using the Short Screening Scale for DSM-IV PTSD and the Brief Trauma Questionnaire.
Over 24 years of follow-up, the team assessed the women's medical records and used American College of Rheumatology criteria to determine the incidence of SLE. A total of 73 SLE cases occurred.
The researchers found that women who met the criteria for PTSD were 2.94 times more likely to develop SLE compared with women who had experienced no trauma.
Furthermore, the results revealed that women who had been exposed to any kind of trauma - regardless of whether they had symptoms of PTSD - had a 2.87 times greater risk of SLE.
According to the researchers, their findings provide further evidence that psychosocial trauma may increase the likelihood of autoimmune disease.
"Our results add to considerable scientific evidence that our mental health substantially affects our physical health, making access to mental healthcare even more urgent."
Dr. Andrea Roberts