The individuals suffering from posttraumatic stress disorder (PTSD) or other stress related-disorder (SRD) are more likely to develop autoimmune diseases, suggests a study published in the journal JAMA.
The study was conducted by Huan Song, Center of Public Health Sciences, Faculty of Medicine, University of Iceland, Reykjavík, Iceland, and colleagues to determine whether there is an association between SRD and subsequent autoimmune disease.
While links between mental stress and physical deterioration have been highlighted before, few previous studies have closely examined the relationship between psychiatric stress and the immune system.
The researchers conducted population- and sibling-matched retrospective cohort study in Sweden from January 1, 1981, to December 31, 2013. The cohort included 106 464 exposed patients with SRDs, with 1 064 640 matched unexposed persons and 126 652 full siblings of these patients. Diagnosis of SRDs, ie, posttraumatic stress disorder, acute stress reaction, adjustment disorder, and other stress reactions. The median age at diagnosis of the disorders was 41 years (interquartile range, 33-50 years) and 40% of the exposed patients were male.
Stress-related disorder and autoimmune diseases were identified through the National Patient Register. The Cox model was used to estimate hazard ratios (HRs) with 95% CIs of 41 autoimmune diseases beyond 1 year after the diagnosis of SRDs, controlling for multiple risk factors.
- During a mean follow-up of 10 years, the incidence rate of autoimmune diseases was 9.1, 6.0, and 6.5 per 1000 person-years among the exposed, matched unexposed, and sibling cohorts, respectively.
- Compared with the unexposed population, patients with SRDs were at increased risk of autoimmune disease.
- The HRs for patients with posttraumatic stress disorder were 1.46 (95% CI, 1.32-1.61) for any and 2.29 (95% CI, 1.72-3.04) for multiple (≥3) autoimmune diseases.
- Relative risk elevations were more pronounced among younger patients.
- Persistent use of selective serotonin reuptake inhibitors during the first year of PTSD diagnosis was associated with attenuated relative risk of autoimmune disease.
- When PTSD patients took commonly prescribed anti-depressants known as selective serotonin reuptake inhibitors (SSRIs) during their first year after diagnosis, however, their risk of developing autoimmune disorders appeared to decline.
Based on the study, the authors concluded that exposure to a stress-related disorder was significantly associated with increased risk of subsequent autoimmune disease, compared with matched unexposed individuals and with full siblings. Further studies are needed to better understand the underlying mechanisms.
For more information log on to 10.1001/jama.2018.7028