Acute stress may be detrimental to fighting off infections like COVID-19 and, therefore, may increase the chance of dying, say scientists.
The discovery was made by researchers led by Dr. Filip Swirski, Director of the Cardiovascular Research Institute at the Icahn School of Medicine at Mount Sinai in New York City.
The researchers first looked at groups of relaxed and stressed mouse models and analyzed their immune systems.
Mice experiencing acute stress showed big changes in their immune system when compared to the relaxed mouse group.
The researchers found that acute stress prompted neurons from the region known as the paraventricular hypothalamus to instantly trigger a large-scale migration of white blood cells from lymph nodes to the blood and bone marrow, thereby diminishing an immune response to viruses.
Researchers noticed that mice, when infected with influenza and COVID-19, mice in the relaxed group fought infection better and got rid of the virus more easily than mice in the stressed group, which were sicker, had less immunity and had a higher death rate from the virus.
Dr. Swirski said: “This work tells us that stress has a major impact on our immune system and its ability to fight infections. It raises many questions about how socioeconomic factors, lifestyle, and environments we inhabit control how our bodies can defend themselves against infection.
“Moving forward, we will need to better understand the long-term effects of stress. It will be particularly important to explore how we can build resilience to stress and whether resilience can diminish stress’s negative effects on our immune systems.”
The discovery – connecting the brain to the immune system – provides a better understanding of how stress affects the body’s response to a virus and why some may be more susceptible to severe illness and worse outcomes.
The work may prompt physicians to further look into the mental state of patients and prompt interventions to help the body better fight infection and improve outcomes, in addition to living a healthier and less stressful lifestyle.