Influence of life events on inflammation, synapses and suicidality

Depression and suicidal behavior are frequently preceded by life stressors that appear to trigger this psychopathology. Most studies have employed rating scales that depend on retrospective recall. Such an approach is open to recall bias. Ecological momentary assessment (EMA) offers a better approach. We employ a method that assesses roughly 2-hour epochs or time periods during waking hours for one-week periods. We have employed this method to detect stress-related increases in suicidal ideation and negative affect. We have shown that this increase correlates with degree of suicide intent in the most recent suicide attempt and it therefore is of great clinical importance. Results from our studies will relate the EMA to the BOLD signal responses to negative autobiographical memories cues during fMRI. How the stressor leads to these psychopathologies has been unclear, but we will report positron emission tomography scans of the TSPO protein as a marker of neuroinflammation. Our findings show that recent life stressors trigger suicidal ideation and depression, and that this relationship is mediated by degree of neuroinflammation. Future applications of these research methods include their potential use as biomarkers of antidepressant and suicidal ideation treatments.