Cytokines and psychiatric symptoms in patients receiving inpatient treatment: The relationship between changes in immune activation and symptoms of mental distress: A 12-week follow-up study of patients with mental health disorders.

Abstract

Patients with common psychiatric diseases like mood disorders and anxiety disorders have often been found to exhibit chronically elevated levels of pro- and anti-inflammatory cytokines when compared to healthy people. Studies have found such associations in cross-sectional assessments, but little is known about how the relationship between cytokines and psychiatric symptom change over time in patients receiving inpatient treatment. It is also unclear if psychiatric diseases precede chronic inflammation, or if chronic inflammation precedes psychiatric diseases, although increasing evidence suggests a bidirectional loop. In addition, the use of anti-inflammatory drugs could mediate such associations. This doctoral thesis aimed to investigate the levels and trajectories of cytokines IL-1β, IL-1RA, MCP-1 and TNF-α and psychiatric symptoms as measured by SCL-90R GSI and BDI-II in a mixed sample of psychiatric patients across 12 weeks of inpatient treatment at Modum Bad Psychiatric Center. The use of anti-inflammatory drugs was taken into account. Patients diagnosed with Post-traumatic stress disorder had higher cytokine levels and showed a more severe development in cytokine levels across the treatment period than patients with depression, anxiety or eating disorder. The cytokines in patients without PTSD were either unchanged or showed decreasing levels across time. Regardless of diagnosis, most patients benefited from treatment, as reported by lower GSI scores at discharge. The levels of IL-1RA and MCP-1 were not associated with the trajectory of psychiatric symptom scores across time, but were associated with psychiatric symptom level. This result was only present in patients who did not use anti-inflammatory drugs, possibly suggesting a mediating effect of such drugs on psychiatric symptoms for patients in treatment.