Stress-related disorders linked to increased risk of life-threatening infections, higher for those diagnosed at younger age
Post-traumatic stress disorder (PTSD) and other stress-related disorders have now been associated with a subsequent risk of life-threatening infections such as meningitis and sepsis. The risk is particularly high among people diagnosed at a younger age and those with other psychiatric conditions. The researchers found that stress-related disorders were linked with a 63% increased risk for meningitis and 57% increased risk for endocarditis (infection of the inner lining of the heart).
“With a specific focus on clinically diagnosed stress-related disorders, we show that severe stress reactions, even transient ones (for example, acute stress reaction), were associated with an increased risk of life-threatening infections, both in short and in the long-term,” say the researchers in their findings published in The BMJ.
Stress-related disorders, including PTSD, acute stress reaction, adjustment disorder, and other stress reactions - refer to a group of psychiatric conditions that are preceded and triggered by a significant life event or trauma. According to the researchers, such disorders are commonly linked to poor mental and physical health.
The team says that evidence also suggests that excessive or prolonged psychological stress compromises several physiological systems, which might increase susceptibility to disease or infections through reduced immunity. However, they add, data on major life-threatening infections, such as sepsis and meningitis, are limited.
To address this knowledge gap, a team of international researchers used the Swedish population and health registers to assess whether severe psychiatric reactions to trauma and other adversities are associated with subsequent risk of life-threatening infections.
The team included researchers from the Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, Iceland; Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm; and West China Biomedical Big Data Centre, West China Hospital, Sichuan University, Chengdu, among others.
“Although relatively rare, severe infections contribute substantially to the global burden of disease because of high fatality, risk of long-term complications, and high healthcare costs. In contrast, stress-related disorders are common in the general population,” the findings state.
The researchers compared infection rates for 144,919 patients diagnosed with a stress-related disorder (PTSD, acute stress reaction, adjustment disorder, and other stress reactions) with 184,612 unaffected full siblings of these patients and a further 1,449,190 unaffected individuals from the general population.
Infections included sepsis, endocarditis, and meningitis, or other central nervous system infections. The average age at diagnosis of a stress-related disorder was 37 years, and participants were monitored for an average of eight years.
During follow-up, new cases of life-threatening infections per 1000 person-years were 2.9 in patients with a stress-related disorder compared with 1.7 in unaffected siblings and 1.3 in unaffected individuals from the general population, shows analysis.
According to the research team, after controlling for family history and other physical or psychiatric conditions, stress-related disorders were associated with all studied infections, with the highest relative risks found for meningitis and endocarditis compared with unaffected siblings.
“Compared with full siblings without a diagnosis of a stress-related disorder, individuals with such a diagnosis were at increased risk of life-threatening infections,” says the study.
It further says, “Younger age at diagnosis and the presence of other psychiatric conditions, especially substance use disorders, were associated with further risk increases.”
The high mortality from these infections, says the research team, calls for increased clinical awareness among health professionals caring for patients with stress-related disorders, especially those diagnosed at a younger age.
They recommend further studies to better understand the roles of lifestyle factors as well as treatments for stress-related disorders in reducing the excess risk of life-threatening infections.
In an editorial, also published in The BMJ, Jonathan Bisson, professor of psychiatry, Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, UK, says: “The finding of increased risk in those with younger age of PTSD onset is important and consistent with the known association between adverse childhood experiences, particularly multiple adverse childhood experiences, and poor subsequent physical and mental health. It could be that people with more complex presentations of stress-related disorders are particularly vulnerable.”