Half of people who die by suicide have no diagnosed psychiatric risk factors, such as depression. It was unclear whether this population was depressed and undiagnosed, or simply not depressed. Genetic research shows that this population is less likely to have genetic risk factors for depression, suggesting that what puts them at risk is meaningfully different.

Major depressive disorder (MDD) is characterized by a lowered mood and loss of interest, contributing not only to difficulties in academic and professional life but also as a major cause of suicide in South Korea. However, there are currently no objective biological markers that can be used for diagnosis or treatment. Amidst this, a research team from KAIST has revealed that depression is not merely a problem of the mind or brain, but is deeply connected to abnormalities in the body's overall immune response. They found that this immune abnormality affects brain function, and the 'Immune Neural Axis' imbalance is the core mechanism of depression, opening up the possibility for the discovery of new biomarkers and the development of new drugs for depression treatment.

University of Utah epidemiologist Mary Jo Pugh leads efforts to better understand veterans’ health outcomes, especially for those with TBI, and how to improve them. Her team has documented several instances where veterans are at greater risk for negative outcomes, such as suicide, cancer,  cardiovascular disease and mental illness.