Does Brain Inflammation Cause Depression?
Millions of Americans suffer with depression, a debilitating illness that can make regular day to day life difficult to navigate. When left untreated or allowed to become severe, depression can have dire consequences. While there are many therapeutic and pharmaceutical treatments available that show promise, scientists are still curious about what causes depression to begin with. Many believe that there could be both genetic and environmental factors that lead to a diagnosis, new research suggests a connection between severe depression and inflammation of the brain.
A study conducted by a team from the Campbell Family Mental Health Research Institute in Toronto, Canada, used brain scans to determine the amount of brain inflammation, if any, on participants who were clinically depressed. There was also a control group of healthy participants, who also received brain scans. The team found that the most severely depressed participants had a 30% increase in brain inflammation over their counterparts. This is the first time that such an increase has been shown, as previous studies have also sought to find out the “chicken and egg” nature of the issue; does inflammation cause depression or is it the other way around?
A study in 2012 at Duke University Medical Center found that there was a connection between a series of depressive episodes and increased levels of an inflammation in the blood. This led scientists to believe that depression must be the cause of the inflammation, especially since inflammation is our body’s way of defending itself from injury or illness. Think about how an ankle swells when twisted, or a goose egg after a bump on the head – this is the body protecting the injury. The new study suggests the old theories are incorrect.
Scientists will now begin to decide if future depression treatments should involve anti-inflammatory properties. Dr. Jeffrey Meyer, an expert in neurochemistry, suggests that the new discovery has very important implications in the development of new and potentially more effective treatments for the many people suffering depression. Finding a new target, brain inflammation, may provide relief for those patients who struggle to find a medication that works. Since 4% of Americans suffer from severe depression, the new treatments could bring great promise.
"Depression is a complex illness and we know that it takes more than one biological change to tip someone into an episode," says Dr. Meyer. "But we now believe that inflammation in the brain is one of these changes and that's an important step forward."
