The Ancient, Genetic Link Between Inflammation and Depression
MILWAUKEE—Depression is genetically linked with inflammation in the body, and the connection goes back to ancient times, Charles L. Raison, MD, told attendees at the Psych Congress 1-Day Regional Meeting here.
“The genes that promote inflammation also promote depression and inflammation directly helps you survive infection,” said Dr. Raison, the Mike and Mary Sue Shannon Endowed Chair in Mind, Body, and Family Well-being and professor, School of Human Ecology and Department of Psychiatry, School of Medicine and Public Health, University of Wisconsin-Madison.
Those genes have been selected throughout human evolution because they “helped organisms survive infection in the days before medicine, hospitals, antibiotics and clean water,” Dr. Raison, a member of the Psych Congress Steering Committee, said in his presentation “The Emerging Role of the Immune System in Depression.”
Infection, Inflammation Tied to Higher Suicide Risk
“Anything that allows you to survive infection, especially early in life, is likely to be retained in the genome,” he said. “Our relationship with microorganisms is the second largest driver of genetic change in humans.”
Today, depressed people who are medically healthy, as a group, demonstrate increased circulating levels of the inflammatory cytokines interleukin-6 and tumor necrosis factor, and acute phase reactant C-reactive protein, according to Dr. Raison.
Infectious and noninfectious dangers such as stress activate peripheral inflammation, which can induce changes in the brain associated with depression, Dr. Raison said.
Genetic Overlap Between Alzheimer's, Immune-Mediated Diseases
“If you made a list of everything that is, on average, biologically different in depressed people vs. nondepressed people, inflammation does every one of those things,” he said.
However, the connection does not make treating depression as simple as prescribing anti-inflammatories, Dr. Raison said. Not all patients with depression demonstrate increased peripheral inflammation, and anti-inflammatory agents may harm patients who do not.
“Just giving depressed people some kind of pharmacologic anti-inflammatory—you’re going to hurt as many people as you help,” he said.
Chronic Sleep Problems Linked to Disability Later in Life
About 107,000 patients are hospitalized each year from complications of nonsteroidal anti-inflammatory drug (NSAID) use, and nearly 17,000 patients with rheumatoid arthritis die from gastrointestinal complications from NSAIDs annually. Furthermore, he said, adding NSAIDs to selective serotonin re-uptake inhibitors significantly increases bleeding risk.
Dr. Raison instead recommended safer methods to recommend for patients to reduce inflammation:
-
Develop a sense of reverence and awe;
-
Eat a Mediterranean diet;
-
Exercise;
-
Don’t live a sedentary lifestyle;
-
Get adequate sleep;
-
Practice meditation;
-
Stay thin;
-
Work to reduce early life trauma/neglect.
Dr. Raison, who has been researching the connection for nearly 10 years, said a “huge” paper will be released on it later this year.
He will speak more about the connection between depression and the immune system at the 29th Annual U.S. Psychiatric & Mental Health Congress, being held in San Antonio, Texas, Oct. 21-24, 2016.
“We’re going to blow this out at Psych Congress,” he said. “We have some new data that really, really highlights this.”
– Terri Airov
References
"The Emerging Role of the Immune System in Depression." Presented at: Psych Congress 1-Day Regional Meeting: June 11, 2016; Milwaukee, WI.
