Researchers have known for some time that depression and immune-system health are linked and can affect each other. Early clinical trials have shown that anti-inflammatory drugs can reduce symptoms of depression, raising hopes that such treatments might be useful in other types of mental illness, such as PTSD.
“I think there’s kind of a frenzy about inflammation in psychiatry right now,” says Christopher Lowry, a neuroscientist at the University of Colorado Boulder. He presented results of experiments probing the link between fearful behaviour and immune response at a meeting in Victoria, Canada, last week of the International Behavioral Neuroscience Society.
Studies of military personnel suggest that immune function can influence the development of PTSD. Soldiers whose blood contains high levels of the inflammatory protein CRP before they are deployed2, or who have a genetic mutation that makes CRP more active3, are more likely to develop the disorder.