Current Position and Future Direction of Inflammation in Neuropsychiatric Disorders

Importance: There has been a large increase in research focusing on inflammation across psychiatric disorders, with the hope of achieving breakthroughs seen with this approach in cancer and other conditions. Current findings suggest that immune-related pathophysiological processes involving inflammation could play a key role for many major mental illnesses. How far reaching this role would be and how soon we can expect translation into treatment, however, remain open questions. Observations: In this narrative review, new evidence from clinical populations, new trials, and preclinical models was summarized. Converging evidence suggests that inflammation plays a significant role in subgroups of patients with psychosis, depression, and autism. Interleukin (IL) 6, T-cell control, immune-metabolic function, and the complement system represent fundamental areas of further research. New treatments have yet to reach clinical impact, but targeted trials are ongoing. Developing and refining human cellular models will aid mechanistic target validation and further understanding of causal pathways and networks. Conclusions and Relevance: To advance to and achieve clinical impact, investigations need to include a collaborative, united effort, pulling information across disciplines and translational scales. A focused approach is needed to validate key emerging targets, where evidence and potential for new and repurposed treatments are strongest.