Stress and autoimmune disease

I am now in my 77th year, and not all that pleased that my inflammatory, immune, and stress systems are becoming more excitable, more likely to be activated by small environmental perturbations that went unnoticed 10 or 20 years ago. Increases in sympathetic nervous system and inflammatory process with aging have been documented in many studies, and there is a literature linking stress with immune system dysfunction at all ages. This post points to yet another study of the linkage of stress with immune system activity. Song et al. report a massive study of over one million people in a Swedish cohort over a thirty year period that shows a strong association between persons suffering stress disorders and increased risk of developing autoimmune diseases such as arthritis and Crohn's disease. This affirms the strong link between psychological stress and physical inflammatory conditions. Here is a truncated and edited statement of results from the JAMA paper:

The median age at diagnosis of stress-related disorders was 41 years, and 40% of the exposed (i.e. suffering from stress-related disorder) patients were male. 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 stress-related disorders were at increased risk of autoimmune disease... Persistent use of selective serotonin reuptake inhibitors during the first year of posttraumatic stress disorder diagnosis was associated with attenuated relative risk of autoimmune disease.