Environmental Stressors May Drive Inflammation and Alter Neurocircuitry to Promote Suicidal Behavior.

Suicide morbidity and mortality are serious public health problems, accounting for over 40,000 deaths annually and over $10 billion in combined medical and work loss costs. Suicidal behavior is the outcome of a complex causal web of distal and proximal risk processes that includes a range of interacting environmental and biological determinants. We review current understanding of risk and protective factors, including recent findings on inflammatory processes, discuss recent research on environmental risks for suicidal behaviors with a focus on economic stress, and examine potential mechanisms by which external factors and internal processes such as inflammation might contribute to pathways leading to suicidal behavior. We propose a model that links changes in the default network or resting state of brain activity with corresponding changes in brain structure and function, which in turn may be influenced by diverse inflammatory mediators, and suggest a potential framework that highlights multidisciplinary opportunities for further research.