Patients with major depressive disorder (MDD) have increased brain levels of a marker of microglial activation, a sign of inflammation, according to a new study in Biological Psychiatryby researchers at the University of Manchester, United Kingdom. In the study, Dr. Peter Talbot and colleagues found that the increase in the inflammatory marker was present specifically in patients with MDD who were experiencing suicidal thoughts, pinning the role of inflammation to suicidality rather than a diagnosis of MDD itself.
“Our findings are the first results in living depressed patients to suggest that this microglial activation is most prominent in those with suicidal thinking,” said Dr. Talbot. Previous studies suggesting this link have relied on brain tissue collected from patients after death.